Παρασκευή 20 Ιανουαρίου 2012

Interview with a practical scientist


An interview with Jamie Hale

I am fortunate enough to interview Jamie Hale, one of the scientists I most admire in the field of nutrition and exercise. Jamie Hale is the author of 7 books, his latest being “Should I Eat The Yolk?”, a must read for those interested in quality nutritional information. Jamie’s work ethic is a unique mixture of an in the trenches understanding of fitness combined with an unbiased scientific approach.
Andreas Zourdos: I know you have trained people from all walks of life, from experienced bodybuilders and MMA athletes to previously sedentary individuals. What is the most underrated factor people tend to neglect in their training?
Jamie Hale: For sedentary trainees the most underrated factor is probably consistency.  It is imperative that workouts and eating regimens are followed consistently, for a substantial period of time.  Working out for one week, then maybe missing a week weakens the chances of attaining goals.  This type of behavior is called instrumental irrationality (cognitive science term).  For competitive athletes the most underrated factor is the difficulty in scheduling the training and nutrition regimen so the athlete peaks at the right team- dialing them in. I know many coaches that have a bag full of training techniques, but haven’t figured out how to combine, and schedule these techniques in the proper manner.  This methodology problem makes it difficult for athletes to peak at the right time.
Andreas Zourdos: There is a tendency for many people to blame genes when it comes to weight loss. What is your response when you come across such opinions?
Jamie Hale: Some genotypes have a harder time than others with weight loss, but that simply means they need to approach things differently.  If a person consistently consumes calories below their average daily metabolic rate weight loss will follow. The problem is how do we get people to follow these guidelines.  The future of nutrition research is the study of behavior modification.   We need to address questions such as- How do we set-up our homes to maximize our nutrition goals?  How does eating with others influence food intake?  What foods decrease appetite?  How does container size and design affect consumption?  How does proximity influence intake? etc..  Genetics do matter, but they do not make weight loss impossible. I worked in a Prader- Will (disorder that includes, among other characteristics, insatiable appetites) Group Home where all of the residents at one time were chronically obese.  Once they were institutionalized they all dropped weight. The staff had complete control of the residents food intake, the clients ate only what was provided by the staff. Their diets consisted of a low calorie mix of carbs, proteins and fats.  Believe it or not, nothing extraordinary- NO low carb, low fat, or food combining.
Andreas Zourdos: What do you think of popular fitness and bodybuilding magazines?
Jamie Hale: I think they contain some good information from time to time, but for the most part should be ignored if you’re looking for reliable information.  Generally, they are packed full of opinions and personal testimonies, which may or may not be useful to the readers.  Scientific information is not the normative in popular fitness magazines.
Andreas Zourdos: How important is compliance when it comes to dieting?
Jamie Hale: If you consistently follow a diet that creates a calorie deficit you will lose weight.  But, as mentioned previously, consistency is the key.  I advise my clients to pick a diet that they will stick with, and not to worry so much about what their friends or magazines advise.  In my books Knowledge and Nonsense , and Diet Sham or Diet Revolution? ,I offer a critique of a various diets.  To reiterate compliance is important, but this doesn’t mean compliance 100% of time.  An occasional variance from the diet is no big deal, as long as this behavior doesn’t become habitual.
Andreas Zourdos: What’s the difference between scepticism and the denial of science?
Jamie Hale:  The word skepticism is derived form the word “skeptikos”- meaning- inquiring. Being skeptical is a good thing, and is a key characteristic of scientific thinking.   Some people believe that skepticism is the rejection of new ideas. Often people confuse “skeptic” with “cynic.” Skepticism is a method used to question the validity of a particular claim. In it’s simplest form skepticism requires evidence for a claim to be accepted as fact (valid evidence doesn’t include “they say” “my instructor says” “the gym staff says” “I have always heard”.). Cynics are distrustful of any advice or information that they do not agree with themselves. Cynics do not accept any claim that challenges their belief system.  The denial of science is the denial of how things really work in the observable universe- Epistemic Irrationality.
Andreas Zourdos: Any plans after writing “Should I eat the yolk”?
Jamie Hale: Currently, I am working on my eight book- How We Know: A Guide To Reason. The book addresses knowledge acquisition, tools for rationality- logic, probabilistic thinking, scientific thinking-, research methodology, and common errors in reasoning and decision-making.  I am also in the process of coming up with a research hypothesis that will be tested at a local University.  The research is in the area of cognitive science.

The demonisation of fructose

By Adam Cunliffe, PhD

There has been much demonisation of fructose as a carbohydrate source for some time. Complex forms of glucose based carbs being the standard public health recommendation. Fructose is metabolised in the liver first to glycogen, then when liver stores are replete, into fat. Given that throughout evolution (excepting the last few hundred years, essentially irrelevant to our metabolic evolution) this sequence of metabolic steps would seem ideal. Ensuring blood sugar control via hepatic glucose release, with the storage of excess calories for any times of famine ahead. I would suggest therefore that the criticisms of these processes only apply to hypercaloric diets and therefore should explicitly state such, before the so called ‘problems’ of fructose are highlighted. As our evolutionary ancestors would have accessed carbohydrates mainly from fructose, it is perhaps not surprising that we deal with it so elegantly in the body (no hyperglycemia/hyperinsulinemia and problems with IGFs) compared to glucose. It seems that excess food, not fructose is a dietary problem. We should be clear about this. Fructose does not tax the pancrease, nor irritate the circulatory system as does glucose, yet remains a source of glucose via the liver as required. The sugar industry is a major sponsor of pro glucose propaganda. I rather suspect however that a peach, an orange or some grapes, remain healthier options than granulated refined sucrose.

Πέμπτη 19 Ιανουαρίου 2012

Supplementary antioxidants and exercise

 By Andreas Zourdos

Dietary antioxidants have gathered the interest of many scientific studies.  A quite long term study presented on the Medicine and Science in Sports and Execise journal by Yfanti and colleagues (2010)  studied the effects of supplemental vitamin C and E. The study concluded that vitamin C and E did not benefit high intensity aerobic exercise and did not influence metabolic or physiologic variables. This study was conducted with muscle biopsies and had a double blind placebo controlled protocol.
Ristaw and colleagues (2009) studied the effects of 1000mg of vitamin C and 400 IU of vitamin E and observed that they prevented an up-regulation of insulin sensitivity due to physical exercise.Blomer (2010) and colleagues studied the supplementation of these two vitamins on weightlifters. He observed that they did not protect against muscle injury or oxidative stress.
My opinion: the antioxidant craze is something far from new for those into fitness. Rarely do most fitness enthusiasts are informed by fitness magazines for the fact there are naturally occurring antioxidants such as peroxidase dismutase  and glutathione peroxidase that are increased with exercise ( I have the notion that this something to with money coming from the supplement companies). This does not mean that the story on exogenous antioxidants is over, but it means one should be less enthusiastic when in it comes to advertisements of vitamins claiming they promote health or performance .

Bibliography
Yfanti C., et al, (2010).Antioxidant Supplementation does not alter endurance training adaptation. Medicine&Science in Sport&Exercise
Ristaw, et al. ( 2009). Antioxidants prevent health-promoting effects of physical exercise in humans.Proceedings of the National Academy of the National Academy of Sciences of the United States of America
Blomer , et al.(2010). Prior exercise and antioxidant supplementation: effect on oxidative
stress and muscle injury. Journal of the International Society of Sports Nutrition.

Nutritional Genomics: Exploring the evidence

By Pantelis Konstantoulakis*PhD and Andreas Zourdos
I have to admit that when I first heard about “nutritional genomics” I was  excited to see what it is all about, that is why I decided to do my own research on this topic.  Genetic tests are held by clinical geneticists and usually will look for rare and incurable diseases. However, some took this idea a bit further.
Is nutritional genomics a science based method?
To explore the relation between genes and diet, we have to understand how the genotype is connected to the phenotype. More than 600 genes, from a total of around 20.000 of the human genome have been correlated with obesity. At this point, it is important to stress that correlation does not imply causation. Some extremely rare mutations of the DNA do indeed lead to increased food intake, and due to this, obesity. Some  well controlled clinical trials that have been published by highly recognised scientific journals and have been criticised but confirmed, have identified the role of three genes. More precisely, the gene of the Melanocortin 4 receptor (MC4r), the  peroxisome proliferator-activated receptor γ (PPARG) and the pro-opiomelanocortin gene(1). In other words, these rare mutations influence our appetite and subsequently they influence calorie consumption, again obesity is a product of overfeeding (2). Nevertheless, no genetic disorder has been confirmed to play a pivotal role on who becomes obese or overweight (3). It is also well recognized by the World Health Organization that obesity is caused by chronic caloric surplus(4). This comes in agreement with fundamental scientific theories , such as the first and second law of thermodynamics.
The genetic disorders related to nutrition are rare or without any scientific significance. A common genetic mutation has to do with folic acid, and who responds well to the supplement form of the vitamin or the chemical form found in nature. It is obvious that this is of little importance and does not determine weight or health.  One common genetic disorder connected with diet is lactose intolerance. Because lactose cannot be digested and absorbed , therefore it cannot cause obesity since it does not affect energy balance. Phenylketonuria is another well known example that can be treated with excluding phenylalanine from the diet.  Again it is becoming obvious that diet-gene interactions are the exception rather than the rule (3,5).
The propaganda of  nutritional genomics also declares that many diseases such as obesity, diabetes, cardiovascular disease and hypertension are due exclusively to nutrition or to isolated nutritional preferences. This is a huge scientific fallacy since it is more than well proven that these diseases depend on the interaction of multiple factors. News flash – but environmental causes and more precisely low socio-economic profile is linked to obesity(3).
This means that people who do not have much to spend will buy and eat the choices that are calorie dense, creating a cheap way to satisfy their appetite, and will get obese due to this , not because there is some diet-gene interaction. Again, the mechanism of storing or losing adipose tissue can be very well understood by the laws of thermodynamics, which are considered fundamental to science , just as the law of gravity. To cut a long story short,  the phenomenon of losing weight is as reproducible as a glass falling on the floor, getting smashed to little pieces. It happens every time. Or maybe those who make a living out of nutritional genomics think that if their clients eat a hyper-caloric diet , they will not gain fat because there is some form of diet-gene interaction.That would be a scientific revelation.

Now, it is really worth to  examine what the other side has to say on the topic:  A Greek study (6) explored the effectiveness of a “nutritional genomics” diet compared to a typical Mediterranean diet and concluded that the “nutritional genomics” group lost  significantly more weight compared to the Mediterranean diet. By carefully reading this study it is striking that it does not take in account energy balance and fails to report the calories of both diets.That is, if there was a difference at this variable then increased weight loss should not be attributed to some hypothetical diet-gene interaction but to the plain obvious, increased negative energy balance. If it was a ceteris paribus comparison – meaning all other variables were equal, then the laws of thermodynamics have failed. Finall, it comes  as a diabolic coincidence that the man in charge of this trial is the distributor of nutrigenomic tests in Greece.
From a psychological aspect, “nutritional genomics” are nothing more than a way to forgive our sins: it is not our fault that we gain fat, some genetic curse is haunting us. In conditions such as obesity, sometimes it is hard for the individual to face reality with honesty and take responsibility. Those on the business of  “nutritional genomics” know that, and that is why the goal post is moved to the genes – by that way lifestyle, personal responsibility and psychological matters are non-significant. Then,  DNA becomes the scapegoat for the guilty past and the Trojan horse for a present time nutritional intervention. In the name of genetics from now on, nutritional advice has a whole new different meaning, since it carries the potential to manipulate one’s genes! How can one not stand in awe? Time now for a reality check:  the evidence for the effectiveness of “nutritional genomics” is non-existent (3,5), just like  the regulation and laws on these matters. It is pretty fair to say that this story is more science fiction than science based. Pompous scientific terminology is not evidence. The truth is that  “nutritional genomics” is the answer to an irrelevant question.

Please check the related article discussion on Colby Vorland's blog here
Bibliography
1. Jackson, JF (1998).Obesity-Leanness included. Online Mendelian Inheritance in Man. www.ncbi.nlm.nih.gov/omim/601665 (accessed July 26 2010).
2. Prentice, AM (2001) Overeating: the health risks. Obesity Research, 9, 234S-238S.
3. Wallace, H. (2006).Your diet tailored to your genes: preventing diseases or misleadingmarketing?GeneWatchUK.www.genewatch.org/uploads/f03c6d66a9b354535738483c1c3d49e4/Nutrigenomics.pdf (accessed July 25 2010).
4. Obesity and Overweight (2010).World Health Οrganization. www.who.int/mediacentre/factsheets/fs311/en/(accessed July25 2010)
5. Sauko, PM et al. (2010). Negotiating the boundary between medicine and consumer culture: Online marketing of nutrigenetic tests. Social Science & Medicine.70(5): 744–753
6. Arkadianos, I. et al. (2007). Improved weight management using genetic information to personalize a calorie controlled diet. Nutrition Journal. 6:29 doi:10.1186/1475-2891-6-29