Probiotics? No. Metabiotics? Yes and more is better

Probiotics, Prebiotics, Synbiotics and Metabiotics

  1. Probiotics: beneficial gut microbiota
  2. Prebiotics: substrate that feeds and promotes growth of beneficial microbiota
  3. Synbiotics: combinations of probiotics and prebiotics
  4. Metabiotics: products of microbiota degeneration or metabolism that provide nutrients and signaling functions that benefit the host

 

Why we should be learning how to boost the gut production of “metabiotics”, the least known and most recently named …biotic

Making sense of the 4 biotics

Following on from successive hysterical food fads comes the stampede to find and sell the next probiotic. And naturally those with more money than sense are throwing it at probiotics but what does scientific plausibility add to the picture?

So far, very few probiotic bacteria or combination of bacteria other than total fecal transplant has been able to modify the microbiome, and why on earth would anyone expect a few bacterial colonies to impact an ecosystem containing up to 10,000 species of micro-organisms and trillions of individual cells.  On the other hand, different diets invariably produce profoundly contrasting microbial patterns. We already know how important substrate is for microbial growth, they bloom with appropriate substrate and vanish just as quickly and become dormant without it.  A probiotic without an ecological niche and substrate to sustain it is unlikely to survive so synbiotics make a lot more sense but still the probiotc component of any synbiotic mixture has yet to be seen to impact the overall complex microbiota ecosystem.

What we do know is: 1. diet and particularly fibre profoundly changes the microbiota and 2. increased species diversity is better than decreased diversity and 3. diverse diets with mixtures of different fibres increase microbiota diversity much more than a single fibre source.

But by what means do the microbiota improve health, certainly not directly because the integrity of the gut permeability barrier, (tight junctions between gut lining cells and thickness of the mucus layer) separates an incredibly hostile concoction of antigens and microbes from gut lining cells and the blood stream.  The microbiota must be kept out to prevent all manner of immune malfunction and inflammation while compounds produced by them, their metabiotics harvested.

Ecology of gut microbiota

The importance of metabiotics should not be surprising as most plant eating animals rely almost exclusively for their nutrition on biproducts of microbial breakdown of otherwise indigestible plant materials. The most important of these metabiotics that we know of are short chain fatty acids (SCFA) but there must be many more as grazing animals build all their body mass eating virtually no digestible protein, carbohydrate or fat and these animals demonstrate a direct relationship between the amount of fibre consumed and microbiota derived nutrients available for growth and energy. This dose response relationship must hold for humans as well, levels of SCFA increase proportionately with fibre intake, mainly acetate, propionate and butyrate, but little is known of how much SCFA is best for man. Whereas the EFSA has so far denied all health claims for “Prebiotics” they have approved several claims for fiber, however the health benefits of fiber go way beyond the simple concept of bowel regularity. Fibre is a powerful antidote to diabetes and its benefits are being linked to many other diseases  (Kim, 2014).  SCFAs are essential nutrients for intestinal cells particularly butyrate which provides colonic epithelial cells their main energy source as well as cell signaling effects that produce profound changes in the structure and function of the whole hind gut  (Riviere).  Further beneficial effects of SCFA are mediated through 2 types of free fatty acid receptors present in cells widely distributed in the body such as CNS, immune cells, fat cells, and insulin producing pancreatic islet cells  (Priyadarshini, 2016). Colonic entero-endocrine cells increase in number and increase production of incretin hormones GLP1 and PYY on stimulation by SCFA  (Konishi, 1984).  GLP1 and PYY suppress appetite and voluntary food intake  (Spreckley, 2015).  GLP1 has multiple beneficial actions across the body but particularly regulating glucose metabolism, pancreatic beta cell function and appetite suppression  (Zietek, 2016). GLP1 agonist drugs are widely used for the treatment of diabetes and obesity but endogenously produced GLP1 is largely responsible for the remarkable cure rate of type2 diabetes with gastric bypass surgery  (Madsbad, 2014). Both GLP and SCFA are involved with preserving intestinal permeability barrier function  (Cani, 2009) and butyrate and propionate are powerfully anti-inflammatory and may reduce autoimmune diseases, allergies and promote oral tolerance of potential food allergens  (Richards, 2016).  The so called ‘Leaky Gut Concept’ may be a triggering event in inflammatory conditions and autoimmune diseases such as colitis, arthritis, asthma, celiac disease and type 1 diabetes  (Marino, 2017) as well as a factor in age-related diseases that are thought to be increased by systemic inflammation such as heart attacks, strokes, cancer, and dementia  (Bourassa, 2016). Recent research links Parkinson’s Disease with “leaky gut” inflammation and recommends fibre pre-biotic nutritional therapies to boost SCFA production  (Perez-Pardo, 2017). Systemic inflammation is a prominent factor in type 2 diabetes and the anti-inflammatory effects of butyrate and propionate may be involved in the observed protection from diabetes with high fibre diets (Meijer).

What is the ideal level of fibre consumption and can you have too much of it?

Risk reduction from heart disease with increasing consumption of fiber

Risk reduction from heart disease with increasing consumption of fiber

This figure from Threapleton’s meta-analysis shows increasing protection against heart attack (CHD) with increasing consumption of fibre. The study suggests larger amounts (60-70 g/day) than current nutritional guidelines (25-35 g/day) would be at least as protective as the 30-40% relative risk reduction claimed in statin trials.  The average carbohydrate consumption in the US is around 500 g/day but that could be replaced with 60-80 plus g/day of fibre and because of the self limiting satiating effect of fiber it’s difficult to eat too much. The effects are transformational, reducing energy intake, eliminating glucose and insulin variability while increasing substrate to promote microbial diversity and SCFA production  (Threapleton, 2013).  For the paleo afficionados, one thing we know is that pre-historic man relied on much more dietary fibre for sustenance possibly 100-200 g/day and from the available studies so far- more is better.

DIABETES EPIDEMIC RESULT OF INSULIN TSUNAMI

Summary

  1. Diets dominated by rapidly absorbed carbohydrates produce chronically high levels of insulin.

  2. Excess Insulin signalling alone can explain obesity, inflammation and insulin resistance progressing to diabetes.

High insulin levels (from diet) cause:

Diabetes

Obesity

Inflammation

 It is important to reduce high insulin levels simply by avoiding rapidly absorbed carbohydrates that spike blood glucose 

 

The Insulin Tsunami

  • Across modern societies most people are experiencing chronically high levels of insulin from diets dominated by rapidly absorbed carbohydrates
  • Insulin is the hormone that directs food into fat stores and high levels of insulin and glucose will constantly syphon calories into fat stores and stimulate increased food consumption for energy needs.
  • Recently Insulin itself has been found to directly increase inflammation throughout the body and diet driven insulin excess may be the precipitating cause of Type 2 Diabetes.
  • Inflammation is the most important risk factor for heart disease, stroke, cancer, etc.
  • No decrease in the epidemic of obesity and diabetes can occur without specifically addressing the route cause—chronically high levels of insulin from diets dominated by rapidly absorbed carbohydrates

Insulin is a vital hormone regulating many more processes than just blood glucose levels such as growth and development but once we are fully grown insulin continues to drive ever increasing waistlines, metabolic disturbances and age related diseases.  Even small amounts, such as 50 grams of rapidly digested carbohydrates spike glucose levels and produce large increases in insulin secretion that not only produce insidious weight gain but a cell signaling pattern that increases our risk of age related diseases. Unfortunately rapidly digestible carbohydrates have become the staple foods of modern societies and it requires a great deal of effort and commitment to avoid them. 50-60% of all calories consumed in the Western Diet are high glycemic starches and sweeteners such as flour, potatoes, rice, corn syrup, corn flour and sugar.

CHEATING THE SYSTEM: GET BENEFITS OF FASTING WITHOUT FASTING

Self-Eating (Autophagy) an ancient process involved in repair & aging, switches on while fasting and is exquisitely sensitive to dietary glucose abundance.

The tools of the “blind watchmaker” (Richard Dawkins on evolution) are serendipity and improvisation.  The first lesson in order to uncover the secrets of biology is to recognize the untidiness of it all, where mechanisms for doing one thing are borrowed to do another and the process repeated ad infinitum; if it works after a fashion, at least to get to the point of sexual maturity then all the better but after that he could care less, however after maturity the human condition involves 70 years or so of decline and unraveling the idiosyncrasies of the blind watchmaker may turn up some benefits to our fragile existence.

This is how I view the evolution of autophagy over a billion years:  A process that worked to preserve the life of single celled organisms when dormant and starved of nutrients has evolved to become a complex and lethally indispensable process for the existence of any form of multicellular animals. Funny that autophagy is unknown to most doctors, its discovery is so new, but its untidiness and improvisation is evident from the numerous overlapping functions it fulfills.  While fasting it provides glucose and fatty acids for energy and amino-acids for assembly of vital new proteins but simultaneously fasting likely improves autophagy’s other improvised roles; it detoxifies cells and stops them gumming up, regulates recycling, healing, repair, cell turnover, immunity and inflammation.  The exciting thing for us is that this vital process is eminently amenable to regulation through lifestyle choices such as exercise and nutrition.  Differentiating between fasting and feasting is critical to survival and a barometer of this switch is the level of glucose in blood and extra-cellular fluid, just 10 grams: a tiny amount compared to energy demands which, if supplied by glucose alone could vary between 0.5 grams per minute at rest to 5 grams per minute while running (clearly 5g per minute form a pool of 10g would be rapidly unsustainable). This delicate sensitivity of blood glucose to feeding argues that glucose is a barometer of energy status and not our primary energy source, this role is  reserved for fatty acids of which we carry hundreds of thousands of Calories in our 10-20% plus body fat. The molecular signaling pathway of this pivotal role of blood glucose is becoming clearer; simply restricting blood glucose reverses the ratio of insulin to glucagon that controls the activation of mTOR that in turn regulates autophagy and numerous other things that influence aging and age related diseases that are now the commonest causes of death and disability,

NO GAS NO GAIN

Headlines across UK media on November 27th 2014

2 MILLION ELIGIBLE TO HAVE GASTRIC BYPASS SURGERY ON THE NHS

No Gas No Gain:  virtually all gastric bypass patients have increased intestinal gas production”

No Joke Bottom line: Increased dietary fiber better diabetes solution than gastric bypass surgery

Alternative headline:
NHS TO TREAT NATIONWIDE DIETARY FIBRE DEFICIENCY WITH GASTRIC BYPASS SURGERY

2 million for GBS no Aldi ad

“NICE” guidelines recommend all diabetics with a body mass index over 35 should be evaluated for gastric bypass surgery. A bariatric surgeons’ spokesperson interviewed on BBC Radio 4 said the procedure produces remission of diabetes within days after surgery independent of any weight loss but the reasons for this improvement are unknown. 10% of the NHS budget goes to treating diabetes and its complications, for example she stated 100 amputations take place every week in NHS hospitals and argued that gastric bypass surgery is a more economical way for the NHS to treat diabetes—now enter the laws of unintended consequences:  COST & COMPLICATIONS.

In my past life as an anesthesiologist I know full well the seriousness of obese patients undergoing any type of surgery and gastric bypass surgery comes with a long list of serious and life threatening complications but among the less serious, virtually everyone has increased gas/flatus production and this is likely the key to its remarkable cure of diabetes.

Contrary to the statement by the bariatric surgeons’ spokesperson, much more is known about the mechanisms whereby gastric bypass but not gastric banding improves diabetes (1) and is likely related to dramatically increased production of certain hormones from intestinal cells in response to undigested food and/or products of fermentation such as short chain fatty acids(SCFA). One of the reasons for assuming fermentation and SCFA’s are important is that virtually all gastric bypass patients have increased intestinal gas production i.e. flatulence, bloating, rumbling feelings and noises, etc. (2). Food consumed by those who have had gastric bypass enters the small intestine downstream avoiding our own digestive enzymes secreted by the pancreas and is therefore available for fermentation by the bacteria which inhabit the gut. These bacteria produce hydrogen, organic gases and carbon dioxide along with SCFA’s which are important intestinal nutrients and signalling compounds that interact with SCFA receptors present at the surface of numerous cell types and organs of the body including immune cells regulating inflammation (3) (4) (5) (6) (7) (8) (9). SCFA’s stimulate receptors in intestinal cells to produce hormones (GLP1) that regulate glucose metabolism and appetite (10) (11) (12) (13) (14).

Conclusions:
Urgent reappraisal of farting as a social stigma is required as one way or another if you want avoid diabetes you take your choice— gastric bypass surgery or up your fibre but either way  avoiding the indiscretion of letting one rip at an embarrassing moment is not an option.

Works Cited
1. Madsbad S, Dirksen C, Holst JJ. Mechanisms of changes in glucose metabolism and bodyweight after bariatric surgery.  Lancet Diabetes Endocrinol 2014;2:152–164.
2. Potoczna N1, Harfmann S, Steffen R, Briggs R, Bieri N, Horber FF. Bowel habits after bariatric surgery. Obes Surg. 2008 Oct;18(10):1287-96. doi: 10.1007/s11695-008-9456-4. Epub 2008 Mar 8.
3. Andrew J. Brown, Susan M. Goldsworthy, Ashley A. Barnes, et al. The Orphan G Protein-coupled Receptors GPR41 and GPR43 Are Activated by Propionate and Other Short Chain Carboxylic Acids.  THE JOURNAL OF BIOLOGICAL CHEMISTRY Vol. 278, No. 13, Issue of March 28, pp. 11312–11319, 2003.
4. Canani RB, Costanzo MD, Leone L, Pedata M, Meli R, Calignano A. Potential beneficial effects of butyrate in intestinal and extraintestinal diseases.  World J Gastroenterol. 2011 Mar 28;17(12):1519-28. doi: 10.3748/wjg.v17.i12. 1519..
5. D. Zapolska-Downar, M. Naruszewicz. Propionate Reduces The Cytokine-Induced Vcam-1 And Icam-1 Expression By Inhibiting Nuclear Factor-K B (Nf-Kb) Activation.  Journal Of Physiology And Pharmacology 2009, 60, 2, 123-131. http://www.jpp.krakow.pl.
6. Patrick M. Smith, Michael R. Howitt, Nicolai Panikov, Monia Michaud, Carey Ann Gallini, Mohammad Bohlooly-Y, Jonathan N. Glickman, Wendy S. Garrett. The Microbial Metabolites, Short-Chain Fatty Acids, Regulate Colonic Treg Cell Homeostasis. Science 341, 569 (2013). DOI: 10.1126/science.1241165.
7. Vinolo, Rodrigues, Nachbar, Curi. Regulation of inflammation by short chain fatty acids. Nutrients 2011, 3, 858-876. doi: 10.3390/nu3100858.
8. Xiao, et al. A gut microbiota-targeted dietary intervention for amelioration of chronic inflammation underlying metabolic syndrome. FEMS Microbiology Ecology, Volume 87, Issue 2, pages 357–367, February 2014.
9. Sebely Pal, Alireza Khossousi, Colin Binns, Satvinder Dhaliwal and Vanessa Ellis. The effect of a fibre supplement compared to a healthy diet on body composition, lipids, glucose, insulin and other metabolic syndrome risk factors in overweight and obese individuals.  British Journal of Nutrition (2011), 105, 90–100.
10. Gwen Tolhurst, Helen Heffron, Yu Shan Lam, Helen E. Parker, Abdella M. Habib, Eleftheria Diakogiannaki, Jennifer Cameron, Johannes Grosse,2 Frank Reimann, Fiona M. Gribble. Short-Chain Fatty Acids Stimulate Glucagon-Like Peptide-1 Secretion via the G-Protein–Coupled Receptor FFAR2. Diabetes 61:364–371, 2012.
11. Holst, JJ. Incretin hormones and the satiation signal. s.l. : International Journal of Obesity (2013) 37, 1161–1168.
12. Ji Hee Yu, Min-Seon Kim. Molecular Mechanisms of Appetite Regulation. Diabetes Metab J 2012;36:391-398.
13. L. Geurts, A.M. Neyrinck, N.M. Delzenne, C. Knauf, P.D. Cani. Gut microbiota controls adipose tissue expansion, gut barrier and glucose metabolism: novel insights into molecular targets and interventions using prebiotics. Beneficial Microbes, December 2013; 4(4): 1-15. ISSN 1876-2833 print, ISSN 1876-2891 online, DOI 10.3920/BM2012.0065 1 .
14. Slavin, Joanne. Fiber and Prebiotics: Mechanisms and Health Benefits.  Nutrients 2013, 5, 1417-1435; doi:10.3390/nu5041417 .

Fallacy 2:  “Detox”

Never underestimate the difficulty of changing false beliefs by facts.  Henry Rosovsky

Fallacies are not just crazy ideas and usually have at least some element of plausibility, “detoxification” sounds like a good thing right, so an industry of snake oil salesmen thrive on nothing more than word association to convince impressionable and naïve people to spend valuable vacation time in detox centers and consume concoctions supposed to clean the liver and digestive tract in a similar fashion to a colonoscopy preparation regime: make no mistake about it those who use the term “detox” in serious conversation are either naïve or unscrupulous and often both.  On the other hand detoxification is a complex and vital process to the health of individual cells and the body as a whole but it’s not something that we can go away one weekend a month for or indulge in the occasional chemically induced episode of diarrhea.  Before we throw the baby out with the bathwater, there are ways to enhance the body’s natural detoxification processes but first we have to better define the biological processes involving detoxifying functions.

Autophagy (self-eating):  At the cellular level substantial amounts of potentially toxic proteins are constantly produced and need to be broken down and recycled in order to prevent cell stress and dysfunction which can ultimately lead to premature cell death and degenerative conditions like dementia.  Sophisticated systems have evolved (autophagy and ubiquitin/proteasome machinery) to recycle not only proteins, but mobilize fats and carbohydrates for energy use during times of fasting.  For instance this is accomplished during sleep where brain cells switch energy resources to the task of clearing a backlog of protein fragments generated during periods of consciousness and we now know that sleep deprivation can cause increased neuronal cell death.  The link between fasting and cell detoxification may explain the beneficial effects of calorie restriction on longevity but also suggests that the sensing mechanisms of fasting, such as lower glucose levels, enhance cellular detoxifying via autophagy as well.  Abundant glucose dramatically increases insulin secretion and the insulin signaling system suppresses autophagy as does high amino acid levels from high protein consumption.

Liver Function:  At the whole body level the liver is the main organ of detoxification of enormous amounts of endogenously produced waste products as well as potentially harmful substances absorbed from what we eat.  Fat soluble waste is excreted into the gut as bile and water soluble waste via the kidneys as urine. The role of water in urine excretion is self-evident but the role of the bile and digestive tract is detoxification is not so widely appreciated.  One of the many remarkable functions of fiber is the enhancement of removal of fat soluble excretory products in bile.

Take Home Message!  Eat low glycemic high fiber foods:  Foods that produce low levels of glucose and only moderate amounts of protein are good for cellular detoxification and high fiber foods are good for liver and gut function.

What to eat and avoid?

Harmful Foods-Minimize these 

Over 70% of calories consumed by children and adults alike are quickly digested carbohydrates resulting in large increases in blood glucose that prompts insulin secretion resulting in fat deposition, stops energy production from fat and increases food consumption and hunger.  Long term effects of frequent spikes of high blood sugar are cell damage and inflammation, hypertension, metabolic syndrome that can lead to serious problems later in life such as heart attacks, strokes, cancer and dementia.

  • Sugar, High Fructose Corn syrup, all caloric sweeteners including honey and agave syrup, sweets & candies. Use low calorie sugar substitutes if necessary
  • All Juices, even orange juice, eat the fruit instead, sodas, energy drinks, gatorade, powerade, grape juice, cranberry juice, etc. Also avoid cocktail drink mixes like margarita and sweet and sour mix.
  • White flour, bread, pasta, cakes, cookies, biscuits, etc.
  • Potatoes, white rice, corn flour products, chips, etc.

 

Beneficial Foods-Instead Choose to Eat High Fiber, Low Glycemic Foods

Carbohydrates can be roughly categorized by the speed of their digestion into simple sugars; the faster the worse for health and slower the better, with fiber on the most beneficial end of the spectrum, which also minimize the amount of simple sugars obtained from your diet. Low glycemic food choices, vast, varied and enjoyable include many foods that were previously stigmatized like eggs, dairy and meat.  Calorie counting is unnecessary if high fiber plant foods are the bulk of your diet as they are satiating and suppress hunger due to slow digestion and low insulin response, in addition they contain thousands of phytonutrients which protect against stress, inflammation and cell damage. 

 

  • Unlimited consumption of salads, leafy green vegetables, whole fruits, and nuts.
  • Moderation but not overindulgence in all sorts of interesting foods, including meat, fish, cheese, butter, eggs, olive oil, rape seed/canola oil, herbs and spices. These are what make foods enjoyable and they are mostly nonfattening and nutritionally beneficial
  • Peas, lentils, legumes and beans are high in protein and fiber good in moderation as they still contain digestible carbohydrates.
  • Whole grains, while much better than refined flour are still high glycemic carbohydrates and counteract ketogenesis if you are trying to lose weight or reverse hypertension and metabolic syndrome. Oat bran and oat germ are an inexpensive alternative, as are wheat bran and wheat germ.
  • Drink: water or tea (green tea), coffee, diet drinks if necessary. Again avoid drinks with any sugar, HFCS, or any other calorie containing syrup.
  • Alcohol: Fine in moderation: red wine may have particular benefits.
  • Supplements most are unnecessary and could even be harmful other than a source of omega3 and vitamin D such as in fish liver oils.

 

 

 

 

HEALTHY FOOD FALLACIES

Never underestimate the difficulty of changing false beliefs by facts.  Henry Rosovsky

Fallacies are not just crazy ideas and usually have at least some element of plausibility, most of the dogma parroted on topics of healthy food by the media, self-serving advertising and common gossip are fallacies.  But if the consequences are a global epidemic of obesity, diabetes and human suffering that threatens to overwhelm our health services and our ability to pay for them; it’s about time to clear up some of the deep rooted fallacies of the “healthy eating conundrum”.

Here follows the first of my fallacy rants  (not necessarily in order of importance)

Vitamins and probiotics for children, or anyone else?  The question itself implies a belief that there may be antidotes for harmful food habits that we don’t want to change and instead a vitamin or probiotic can fix the problem.  The simple answer is that there is no antidote to harmful foods and vitamins are just as likely to be damaging as helpful to children’s’ health and “probiotics” are a seriously flawed concept anyway:  to cut to the chase, save your money and don’t bother with vitamins and probiotics.  However, no-one is likely to change unless they believe strongly enough that it is necessary to do so.  But there is no magic or medicine that can undo damage better than prevention in the first place, therefore, it is vitally important to avoid harmful foods-This is almost impossible if you fall in line doing what everyone else does but we are killing our kids with “kindness”, sweet treats, ice cream, sodas, juices, etc. and doing what everyone else does will get you the result that the majority already have; overweight, inactivity and worse, the risk of diabetes, heart attacks, strokes, cancer, the list goes on.

All things necessary to life are toxic, the key is the dose

All biologically active substances are toxic outside of their homeostatic range: that includes water, oxygen, salt, glucose, protein, everything inside our cells and circulation is just as toxic above as below its normal range, “the Goldilocks Phenomenon” applies to all of these things.  Vitamins have been known for 80 years or so, numerous studies have been carried out on possible health benefits of vitamin supplements none have been helpful but more important several studies on vitamins and antioxidants have shown deterioration instead and it is scientifically plausible that this should be so.  Foods contain thousands, maybe hundreds of thousands of necessary nutrients including vitamins and minerals and it is the interaction of multiple ingredients in highly variable food patterns such as the “Mediterranean Diet” that have been found most beneficial.  However, the food we eat is also food for the trillions of micro-organisms that exist in our digestive system (the microbiome) and the importance of this relationship is only just beginning to be discovered.

Prebiotics more useful than Probiotics?

What are probiotics and how do they help us?   The Probiotic concept is that some bacteria have a beneficial effect on gut function and overall health.  To accomplish this they may thrive and replace harmful bacteria and produce beneficial “fermentation products”.  There is no doubt that our health benefits from a symbiotic relationship with gut microbes, however, the gut has trillions of micro-organisms, at least 1,500 and some estimate over 30,000 different species with a combined mass of 1-2 kg and like an algal bloom in the Gulf of Mexico, gut microbes can proliferate in favorable nutrient conditions but the seeds for growth are already present and ubiquitous. The reasons claims for health benefits for probiotics have been repeatedly denied by US and EU authorities are that eating a food containing 1 or 2 species of bacteria has never been shown to have an effect on the hugely complex pattern of organisms further down the digestive system and at any rate sufficient substrate is required for significant numbers of bacteria and fermentation products to have an effect.  On the other hand different diets have been shown to have profound effects on the microbiome and the quantity of beneficial fermentation products that they produce this is the basis of the prebiotic concept where resistant starches and fibers provide substrate for proliferation of bacteria that produce beneficial fermentation products such as short chain fatty acids.

 What to eat and avoid?

 Harmful Foods-Minimize these  

Unfortunately over 70% of calories consumed by children and adults alike are quickly digested carbohydrates resulting in large increases in blood glucose that prompts insulin secretion resulting in fat deposition, stops energy production from fat and increases food consumption and hunger.  Long term effects of frequent spikes of high blood sugar are cell damage and inflammation, hypertension, metabolic syndrome, all things that can lead to serious problems later in life such as heart attacks, strokes, cancer and dementia.

  • Sugar, High Fructose Corn syrup, all caloric sweeteners including honey and agave syrup, sweets & candies. Use low calorie sugar substitutes if necessary
  • All Juices, even orange juice, eat the fruit instead, sodas, energy drinks, gatorade, powerade, grape juice, cranberry juice, etc. Also avoid cocktail drink mixes like margarita and sweet and sour mix.
  • White flour, bread, pasta, cakes, cookies, biscuits, etc.
  • Potatoes, white rice, corn flour products, chips, etc.

 

Beneficial Foods-Instead Choose to Eat High Fiber, Low Glycemic Foods

Carbohydrates can be roughly categorized by the speed of their digestion into simple sugars; the faster the worse for health and slower the better, with fiber on the most beneficial end of the spectrum, which also minimize the amount of simple sugars obtained from your diet. Low glycemic food choices, vast, varied and enjoyable include many foods that were previously stigmatized like eggs, dairy and meat.  Calorie counting is unnecessary if high fiber plant foods are the bulk of your diet as they are satiating and suppress hunger due to slow digestion and low insulin response, in addition they contain thousands of phytonutrients which protect against stress, inflammation and cell damage. 

  •  Unlimited consumption of salads, leafy green vegetables, whole fruits, and nuts.
  • Moderation but not overindulgence in all sorts of interesting foods, including meat, fish, cheese, butter, eggs, olive oil, rape seed/canola oil, herbs and spices. These are what make foods enjoyable and they are mostly nonfattening and nutritionally beneficial
  • Peas, lentils, legumes and beans are high in protein and fiber good in moderation as they still contain digestible carbohydrates.
  • Whole grains, while much better than refined flour are still high glycemic carbohydrates and counteract ketogenesis if you are trying to lose weight or reverse hypertension and metabolic syndrome. Oat bran and oat germ are an inexpensive alternative, as are wheat bran and wheat germ.
  • Drink: water or tea (green tea), coffee, diet drinks if necessary. Again avoid drinks with any sugar, HFCS, or any other calorie containing syrup.
  • Alcohol: Fine in moderation: red wine may have particular benefits.
  • Supplements most are unnecessary and could even be harmful other than a source of omega3 and vitamin D such as in fish liver oils.

 

 

 

 

Inactivity: The Chicken or the Egg?

Influence of Diet on Voluntary Physical Activity?

Explanations of how high glycemic foods as well as fiber deficiency can directly influence physical activity and exercise habits and lead to a vicious cycle of increased obesity and inactivity. 

 Physical activity is very important to health and longevity and to a certain extent exercise can help lose weight from fat stores but few of us have the time, dedication or body strength needed to lose weight by exercise alone: consider that an hour of fast running consumes around 1000 Calories and 10 kg of fat contains 90,000 Calories.  Nevertheless, many regard lack of exercise the main reason for rising obesity rates in children and adults alike but evidence suggests the type of foods we eat can suppress spontaneous activity and the natural desire for playful exercise.  These same foods fail to satisfy hunger and therefore lead to a vicious circle of overeating and inactivity.

In other pages of this blog we describe how high glycemic carbohydrates (sugar, flour, potatoes, rice, etc.) make up 60% or more of our staple foods and after every meal, day after day year after year, elevate blood glucose 2-3 fold and insulin levels more than 10 fold. There are numerous detrimental biological consequences of such changes and amongst them is an avoidance of physical activity.  This notion is supported by a recent study whereby laboratory animals were fed either a high glycemic or low glycemic diet.  Voluntary physical activity was 45% higher for the Low Glycemic fed mice after 38 weeks of feeding. The authors concluded that dietary composition can affect physical activity level (1) in addition body composition was changed by the type of food not energy intake and the high-GI diet caused a pre-diabetic condition which other studies suggest affect up to 30% of adolescents in the USA (2).

Basic science research has revealed some of  the biological mechanisms whereby physical activity can be suppressed by the type of food we eat:    Most people will be familiar with the overwhelming lack of energy and need for rest that occurs with illness for example a bout of “flu”.  Inflammatory cytokines, produced by activated immune cells, induce “sickness behaviour” (1) (3) which is essentially avoidance of physical activity.  Inflammation is associated with depressive symptoms, anxiety and invokes fatigue and reduced movement (3), anti-inflammatory compounds can block/reverse many of these changes (3).  A much milder form of sickness behavior may be brought about by low grade inflammation associated with high levels of blood glucose (and fructose) after meals containing large amounts of high glycemic starches and sugars documented by increased levels of markers of inflammation in these situations (5).  A more recent study has shown increased intestinal wall permeability in obese individuals associated with inflammation and its reversal with a low glycemic high fiber diet  (6).  Several other possible interactions exist such as the suppression of mitochondrial biosynthesis with high levels of insulin brought about by high glucose may directly decrease exercise tolerance.  High glucose also increases stress by increasing production of reactive oxygen molecules and widespread glycation of proteins results in serious impairment of cell function (7).

Although the science may seem complicated the take home message is simple: avoid high glycemic foods and eat much more fiber.  The sad reality is that trying to follow such a lifestyle choice is very difficult as just the opposite, high glycemic low fiber foods dominate our food culture and supermarkets.

1. Inflammatory modulation of exercise salience: using hormesis to return to a healthy lifestyle. Alistair V Nunn, Geoffrey W Guy, James S Brodie, Jimmy D Bell. s.l. : Nutrition & Metabolism , Vols. 2010, 7:87.

2. The Prevalence of the Metabolic Syndrome Among a Racially/Ethnically Diverse Group of U.S. Eighth-Grade Adolescents and Associations With Fasting Insulin and Homeostasis Model Assessment of Insulin Resistance Levels. R. Jago, T. Baranowski, J. Buse, S. Edelstein, P. Galassetti, J. Harrell, F. Kaufman, B. Linder, and T. Pham. s.l. : Diabetes Care, Vols. 31:2020–2025, 2008.

3. Inactivation of the cerebral NFkappaB pathway inhibits interleukin-1beta-induced sickness behavior and c-Fos expression in various brain nuclei. Nadjar A, Bluthe RM, May MJ, Dantzer R, Parnet P. s.l. : Neuropsychopharmacology , Vols. 2005, 30:1492-1499.

4. Inflammation and its discontents: the role of cytokines in the pathophysiology of major depression. Miller AH, Maletic V, Raison CL:. s.l. : Biol Psychiatry, Vols. 2009, 65:732-741.

5. High–glycemic index carbohydrate increases nuclear factor- B activation in mononuclear cells of young, lean healthy subjects. Scott Dickinson, Dale P Hancock, Peter Petocz, Antonio Ceriello and Jennie Brand-Miller. s.l. : Am J Clin Nutr, Vols. 2008;87:1188 –93. http://www.ajcn.org/cgi/content/full/87/5/1188.

6. Xiao, et al. A gut microbiota-targeted dietary intervention for amelioration of chronic inflammation underlying metabolic syndrome. s.l. : FEMS Microbiology Ecology, Volume 87, Issue 2, pages 357–367, February 2014.

7. Dicarbonyls linked to damage in the powerhouse: glycation of mitochondrial proteins and oxidative stress. N Rabbani, P Thornalley. s.l. : Biochem Soc Trans., Vols. 2008 October ; 36(Pt 5): 1045–1050. doi:10.1042/BST0361045.

 

 

Can you consume too much fiber?

Higher consumption of dietary fiber has been associated with lower risk of death from all causes as well as cardio-vascular diseases such as heart attack and stroke.  A recent analysis of most of the published population studies on fiber and cardio-vascular diseases was published in the British Medical Journal and here is a link to the original paper: Dietary fibre intake and risk of cardiovascular disease: systematic review and meta-analysis. BMJ 2014.

Figure 2 from the paper is shown below and illustrates relative risk (RR) of a heart attack (CHD) with varying degrees of fiber consumption from all sources.  Note that less than 20 grams a day is associated with increased risk (10 gms a day corresponds to a RR of around 1.3 means a 30% increased risk of a heart attack or similar event).  To put this into perspective a RR of 1.3 is of the same order found to be  associated with raised LDL cholesterol and taking Statins reduces the risk of coronary heart disease by around 10 to 20% i.e. RR 1.1 to 1.2.  It is interesting to note that food consumption studies reveal that the majority of UK and US people consume around 10 grams of fiber a day, much less than the recommended 30 grams a day.

 

Risk reduction from heart disease with increasing consumption of fiber

Risk reduction from heart disease with increasing consumption of fiber

The study found a dose response relationship between fiber intake and cardio-vascular disease where each 7 gm increase decreased risk by about 9%.  They projected a possible 40 to 50% reduction in risk with fiber intake of 60 to 70 grams per day.

  1. How can one consume 70 plus grams of fiber a day?
  2. Is there a downside?

A fascinating study by Jenkins et al 2002 sheds some light on these questions, and the original paper can be accessed here: The Garden of Eden: plant based diets and the genetic drive to conserve cholesterol and its implications for heart disease in the 21st century.  

Three diets were compared in the study and one of them was a plant based diet containing 145 grams of fiber per day.  This diet was intended to mimic that which our ancestors the great apes might have consumed between 5 and 10 million years ago, however all the food was purchased at a local supermarket.  The following extract from the study goes a long way to answer the two questions:

It consisted of large amounts of leafy vegetables, nuts (almonds and hazelnuts), and fruit, some tropical, but all purchased in local grocery stores. Theoretically, all these foods could be eaten raw but the majority of vegetables were eaten cooked. The diet was effectively devoid of any significant amount of starch. The major feature of the Simian diet was the large volume and the length of time spent eating. Considerable pressure had to be brought to bear on the subjects to ensure they ate all their food and did not lose weight. The foods were palatable but the volume (5.5 kg/d for a 70-kg man) was excessive. At the end of the 2-week diet periods of weight maintenance, LDL-cholesterol was  reduced on the Simian diet by 33%, on the Neolithic diet by 23% and on the therapeutic diet by 7%.  Analysis of the diet for components, which might alter cholesterol metabolism, showed that the Simian diet provided approximately 1 g of plant sterols daily, 145 g of fiber and 92 g of vegetable protein and on an average, over 70 g almonds or hazelnuts per day. 

The study gives support to several purported benefits of high fiber diets:

  1. There was no downside for consuming a relatively massive amount of 145 grams of fiber per day.
  2. On the contrary fiber consumption was a powerful limiting factor regarding total calorie intake: Considerable pressure had to be brought to bear on the subjects to ensure they ate all their food and did not lose weight. 
  3. The high fiber Simian diet quickly and dramatically improved subjects’ cholesterol profiles

For those wishing to control their weight there is a warning sign from the study in that whole grain cereals are regarded as the obvious source of fiber but they are also the major source of high glycemic starch in our diet and attempts at eating more whole grains to maximize fiber consumption runs the risk of weight gain with high blood sugar and insulin levels.  For instance whole wheat contains 61% starch as well as 12% fiber and in order to get 48 gms of fiber from this source one would have to simultaneously consume 244 gms starch and 56 gms protein, an extra 1200 calories.  In order to achieve adequate fiber without weight gain there is a need to replace whole wheat flour used in staples like bread, pasta, cakes and cookies with low carb/high fiber formulations (www.fiberflour.org).

 

Life Cycle of an Energy Producing Protein

ATP synthase is a most amazing molecular machine found in mitochondria that produces ATP, the cell’s most important energy carrier, its main component rotates at 300 cycles per second driven by a cascade of 1,000 hydrogen ions to produce a hundred ATP molecules a second.

I want to use the life cycle of this molecular machine, which makes life as we know possible, to illustrate the importance of obligatory recycling of living material and the influence of lifestyle decisions on those processes.  ATP synthase has a half life of around 40 hours, therefore no ATP synthase exist in your body for longer than 5 days. This means that every living cell has to dismantle and rebuild all of its ATP synthase within 5 days and in order to maintain a stable energy supply without excessive accumulation of waste material, the production of new ATP synthase must be matched with the recycling of old:  this is a hugely expensive undertaking in terms of energy and resources for the organism and clearly must be necessary for survival.  The reason for such a high turnover of all proteins in the body is that they become damaged and dysfunctional quite rapidly. Specific identification and removal of dysfunctional proteins is complex and highly regulated, carried out in proteosomes and a process called autophagy. Deficiencies in autophagy are thought to be responsible for many degenerative conditions such as dementia, Parkinson’s, and aging in general.  A lethal childhood condition Batten Disease, is caused by inadequate dismantling and therefore intracellular build up of dysfunctional ATP synthase proteins.

So how do lifestyle decisions affect protein synthesis and autophagy? Diet and Exercise!

Nutritional factors have a major controlling influence on autophagy; high levels of amino acids and glucose suppress autophagy and fasting particularly starvation powerfully activates it. The main pathway to suppress autophagy is through a master-controller (mTOR) that is controlled amongst other factors by insulin and glucagon, note that these hormones are regulated primarily by blood glucose levels and to a lesser degree amino-acids.  Simply put glucose and amino-acids suppress autophagy while low levels of both enhance it.  Many of the health benefits of calorie restriction are though to be due to activation of autophagy.  However enhancement of autophagy may also be achieved by  specific avoidance of raised glucose and excessive protein intake without the difficulties associated with generalized calorie restriction.

On the synthesis side diet; acting through insulin and glucagon, as well as exercise and other environmental circumstances have a controlling influence on  muscle and mitochondrial biosynthesis acting through the master-controller transcription factor (PGC1alpha), as seen in the figure below from this linked reference.

Aweurx Continue reading

Endurance Performance and Mitochondrial Function

Hypothesis: Improvements in aerobic capacity and injury recovery might be achieved by nutritional strategies specifically targeted at improving mitochondrial function by both enhancing mitochondrial biogenesis and recycling dysfunctional proteins by autophagy.

Endurance performance is closely predicted by oxygen consumption at the anaerobic (or lactate) threshold (VO2LT) and VO2LT is proportional to muscle mitochondrial volume.  The evidence for mitochondrial function being the performance limiting factor at or above the anaerobic threshold is that lactate is generated from exercising muscle in spite of adequate blood supply and oxygen availability and therefore “anaerobic threshold” is something of a misnomer and Lactate Threshold (LT) would be a more accurate term.  Lactate is generated due to rapid increase in ADP/ATP ratio from working muscle.  The increased ADP levels must be converted to ATP within mitochondria by the ATP synthase protein complex associated with the Electron Transport Chain and no matter how much oxygen is being transported to the muscle conversion of ADP to ATP is limited by the amount of functioning ATP synthase molecules in the exercising muscle.

Experience athletes will be very familiar with how much effort and work rate they can sustain at and above their LT as exceeding LT for brief periods during endurance performance quickly leads to hyperventilation and exhaustion.

While VO2max is vitally important to athletic ability it is a relatively stable attribute of athletes, however VO2LT and the ratio of VO2LT/VO2max are better indicators of ability in endurance sports (1) and is also more responsive to training.

VO2LT is essentially maximum sustainable Aerobic Enzyme Activity and is dependent on mitochondria number and enzyme density.  Muscle biopsy studies in humans have shown mitochondria are highly responsive to exercise and can increase with 6-8 weeks of training and decrease within 6-8 weeks of detraining (2).  Peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) is the master controller of mitochondrial biogenesis and is in turn controlled by both physical activity and nutrition (3).

Attempts at improving athletic performance in humans and animals through various dietary modifications have been tried before with varying results. Traditionally high carbohydrates were in vogue but more recently attempts at stimulating fat metabolism in order to spare glycogen stores have been tried.  In summary low carbohydrate/high fat interventions over several weeks, were more effective than interventions over days and tests of endurance were improved more than tests of sprints, but it is fair to say that there have been few if any deteriorations in endurance performance in studies on high fat diets as long as sufficient time for adaptation was allowed (4).  There have been no studies with the specific goal of monitoring VO2LT, the physiological parameter that is closely linked to mitochondrial biogenesis.  Two recent studies document greater mitochondrial enzyme enhancement while training in fasted (2) and glucose withheld conditions (5)  but with no dietary change between training sessions.  The most up to date review by the Australian group (4)  used short term high fat diets that still had substantial carbohydrate content and therefore were unlikely to create conditions for enhanced mitochondrial biogenesis.

“Train Low perform High”  This catch phrase has been used to guide the concept of fat enhancement during training, the idea is to train on a low carb/ketogenic diet and high carb load only 24 hours or so before a competitive event.

  • The suggested diet for individual athletes to be test should be enjoyable and encompass most of what is already known to be beneficial but with a strict avoidance of hyperglycemia inducing a mild ketogenic state by replacing high glycemic carbohydrates with plant foods high in fiber water and phytonutrients. Protein of not more than 2 gm/kg/day from meat, fish, poultry, eggs, dairy and the bulk of food consumed from unlimited amounts of fruits, nuts, vegetables, salads, oils and dressings with lots of herbs and spices.  In this way relatively large and satisfying meals would supply the majority of calories from slowly digested carbohydrates, fats, oils and short chain fatty acids from prebiotic fiber fermentation.
  • Carbohydrate restoration for competitive events can be achieved by increasing carbohydrate intake 1 day prior to competition in order to increase muscle glycogen content.
  • Improvement should not be expected in less than 4 weeks, neither should significant performance improvement occur during training because muscle glycogen will be depleted on a ketogenic diet, however muscle proteins that generate energy from fat oxidation should gradually increase ultimately resulting in glycogen sparing and greater endurance performance.

 Cell Signalling Pathways controlling mitochondrial function

  • Hyperglycemia and insulin suppress PGC1 by Akt/PKB removing fox01 from the PGC1 promoter.
  • Glucose produces ATP & NADH through extra-mitochondrial glycolysis; decreases cytosol NAD+ inhibits SIRT1 which activates PGC1 through deacetylation Fig 2.
  • A mild ketogenic state brought about by low dietary glucose availability increases PGC1, via glucagon action and direct effects of changes in free fatty acid levels (FFA) and ketone bodies on nuclear gene transcription.
  • Insulin profoundly suppresses FFAs which are ligands for several transcription factors (PPARs & Free Fatty Acid Receptors) that interact with PGC1 in the promotion of mitochondrial protein synthesis.

 Energy Production, mitochondrial recycling and cell maintenance

Mitochondria are constantly destroyed and re-synthesized with estimates in rats for half-lives in; liver, 9.3 days; testes, 12.6; heart, 17.5 and brain 24.4 days (6). Cell proteins are broken down by proteasomes (7) and whole organelles by autophagy. Mitochondrial mass is increased through biogenesis rather than decreasing mitophagy (8) which is necessary for cell maintenance as blocking autophagy accelerates apoptosis and prevents the life extension and metabolic improvements associated with calorie restriction and sirtuins. (9) (10) (11).

The likely mechanisms whereby mitochondrial function is controlled through substrate and hormone levels are described in a review by Douglas Wallace (10): Very simply high glucose and insulin levels inhibit mitochondrial biogenesis while it is stimulated by glucagon, fatty acids and ketone bodies (12).  There is a sea change in nuclear signaling inside cells that pivots around the abundance of glucose. Glycolysis takes place in cytosol producing higher NADH/NAD+, whereas fatty acids and ketone bodies are metabolized in mitochondria and thus increase cytosolic NAD+ which activates SIRT1, a deacetylase which counteracts the acetylation and consequent deactivation of FOXO and PGC1.  The controlling effect of glucose on pancreatic secretion of either insulin or glucagon is another pathway regulating mitochondrial biogenesis through the master controller PGC1 as shown in the figure below (13).  In addition the intensity of physical activity directly increases PGC1 transcription in muscle cells and increases sympathetic tone suppressing insulin and increasing glucagon pancreatic secretion, both glucagon and adrenergic receptors activate the cAMP-PKA mediated increase in PGC1 transcription (13) (14) (10).

insulin glucagon pathways and PGC1

Regulation of PGC-1 Promoter Activity by Protein Kinase B and the Forkhead Transcription Factor FKHR.

Daitoku, Hiroaki; Yamagata, Kazuyuki; Matsuzaki, Hitomi; Hatta, Mitsutoki; Fukamizu, Akiyoshi

Diabetes. 52(3):642-649, March 2003.

 

AweurxTranscriptional regulation of the PGC-1 promoter by FKHR and CREB. A schematic model for PGC-1 gene transcription mediated by FKHR (FOXO) and CREB through each responsive element via different hormone signals. Left: insulin activates PI3 kinase signaling pathway, which stimulates phosphorylation of FKHR by PKB (Akt), followed by nuclear exclusion and repression of PGC-1 gene transcription. Right: Glucagon activates cAMP signaling pathway, which stimulates phosphorylation of CREB by PKA, and thereby induces the expression of PGC-1. (13)

  Ketogenic Diets Stimulate Systemic Mitochondrial Biogenesis

The Ketogenic Diet was designed in the 1920’s as a starvation mimicking diet, since starvation was known to limit seizures (15).  The classical KD; high fat, very low carbohydrate, was an effective treatment for epilepsy but fell out of favor with the development of phenytoin in 1938 but has experienced a resurgence in use over the past 20 years, particularly in the treatment of refractory epilepsy (16).  Less rigid versions of the classical KD have been used with equal efficacy such as the low glycemic treatment (17) and modified Atkins diet (18).  Not only are seizures decreased in children with epilepsy but improvements were noted in behavior and cognitive functions (16) (19) (20). A great deal of research has gone into the mechanisms involved and widespread improvements in energy metabolism have been documented (21).  Mitochondria from animals fed a ketogenic diet produced less reactive oxygen species (ROS), mitochondrial density increased and numerous proteins involved in oxidative phosphorylation increased in the hippocampus in addition to anti-apoptosis mechanisms (20).  Neuroprotective effects of a KD have been reported in Parkinson’s disease and Alzheimer’s disease (20).  Improvements in Autism have been reported (22) and this is not surprising given the links between Autism, ADHD and mitochondrial dysfunction (23) (24) (25).

The benefits of ketogenic diets are not confined to nerve tissue similar improvements in mitochondrial function have been documented in muscle (26), heart (27) and liver (28) and there is a systemic increase in mitochondrial and antioxidant enzymes brought about by PGC1 and NRF2 (nuclear respiratory factor) (28).

 The ketogenic diet has also been used very effectively for weight loss for at least 100 years (29) and popularized by the Atkins Diet in the 1970’s.  Atkins was demonized by the medical establishment of the time because he was advocating a high fat diet that was thought to increase the risk of cardiovascular disease.  However, epidemiologic studies, controlled trials and basic science investigations over the last 10 years have shown that ketogenic and carbohydrate restricted diets actually improve both CVD risk factors and outcomes (30) (31) (32) (33) (34) (10) (14).  Objections to the classical ketogenic diet due to palatability, lipid profile and complications such as constipation can be overcome by consuming the bulk of one’s food in the form of low glycemic plant foods that have a high water, fiber and phytonutrient content but low glucose availability (31) (35) such as “Eco-Atkins” (36) and a Spanish Ketogenic Mediterranean diet (37) resulting in dramatic improvements in lipid profiles over control diets containing more carbohydrates.  (38) (39)

Works Cited

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2. Raising plasma fatty acid concentration induces increased biogenesis of mitochondria in skeletal muscle. Pablo Garcia-Roves, Janice M. Huss, Dong-Ho Han, Chad R. Hancock, Eduardo Iglesias-Gutierrez, May Chen, and John O. Holloszy. s.l. : PNAS , 2007, Vols. June 19, 2007 vol. 104 no. 25 10709–10713.

3. Regulation of PGC-1a, a nodal regulator of mitochondrial biogenesis. Pablo J Fernandez-Marcos, and Johan Auwerx. s.l. : Am J Clin Nutr 2011;93(suppl):884S–90S.

4. Wee Kian Yeo, Andrew L. Carey, Louise Burke, Lawrence L. Spriet, and John A. Hawley. Fat adaptation in well-trained athletes: effects on cell metabolism.

5. Beneficial metabolic adaptations due to endurance exercise training in the fasted state. Karen Van Proeyen, Karolina Szlufcik, Henri Nielens, Monique Ramaekers, and Peter Hespel. s.l. : Journal of Applied PhysiologyJanuary 2011 vol. 110 no. 1 236-245.

6. The Turnover of Mitochondria in a Variety of Tissues of Young and Aged Rats. Robert Menzies and Phillip  Gold. s.l. : THE JOURNAL OF BIOLOGICAL CHEMISTRY, 1971, Vols. Vol. 246, No. 8, Issue of April 25, pp. 2425-2429, 1971.

7. Oxidative Stress-Mediated Regulation of Proteasome Complexes. Charity T. Aiken1, Robyn M. Kaake1, Xiaorong Wang1, Dr. Lan Huang (lanhuang@uci.edu). s.l. : The American Society for Biochemistry and Molecular Biology, Inc., 2011, Vols. MCP Papers in Press, Published on January 31, 2011 as manuscript R110.006924.

8. Selective degradation of mitochondria by mitophagy . Insil Kim, Sara Rodriguez-Enriquez, John J. Lemasters. s.l. : Archives of Biochemistry and Biophysics , 2007, Vols. 462 (2007) 245–253.

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11. Can Autophagy promote longevity. Frank Madeo, Nektarios Tavernerakis, Guido Kroemer. 9: September 2010, s.l. : Nature Cell Biology, 2010, Vol. 12.

12. Regulation of PGC-1 Promoter Activity by Protein Kinase B and the Forkhead Transcription Factor FKHR. Daitoku, Hiroaki, et al., et al. s.l. : Diabetes. , 2003, Vols. 52(3):642-649, March 2003.

13. Regulation of PGC-1 promoter activity by protein kinase B and the Forkhead Transcription Factor FKHR. Daitoku, Hiroaki, et al., et al. s.l. : Diabetes, 2003, Vols. 52 (3): 642-649, March.

14. A Mitochondrial Paradigm of Metabolic and Degenerative Diseases, Aging and Cancer: A Dawn for Evolutionary Medicine. Wallace, Douglas C. 359, s.l. : Annu Rev Genet, 2005, Vol. 39.

15. The effect of ketonemia on the course of epilepsy. Wilder, R M. s.l. : Mayo Clinic Bull., 1921, Vol. 2: 307.

16. History of the ketogenic diet. Wheless, James W. s.l. : Epilepsia, Wiley Periodicals, 2008, Vols. 49, 3-5.

17. Efficacy, safety, and tolerability of the low glycemic index treatment in pediatric epilepsy. Muzykewicz DA, Lyczkowski DA, Memon N, Conant KD, Pfeifer HH, Thiele EA. :1118–26. doi:10.1111/j.1528-1167.2008.01959.x. PMID 19220406, s.l. : Epilepsia. , 2009, Vol. 2009 May;50(5).

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