Post by Cliff Harvey ND
Peter Rana – founder of BodyTech Gyms (and apparent expert on all things health, fitness and nutrition) has recently come out guns blazing against the Paleo diet in this article: [HERE]
Rana’s lack of understanding of both Paleo as a dietary concept and fundamental tenets of nutrition is baffling.
He suggests: “Sorry Paleo dieters” “The Paleo diet is seriously flawed” and claims that the very foundation upon which it is based is unsound. I fail to see how a diet that promotes the eating of liberal amounts of real food can cause such an outcry….
BUT he goes on to say that “Statements such as "fat, not carbohydrate, is the preferred fuel for human metabolism and has been for all human evolution" are unfounded and contradict human biochemistry.”
When in fact any good nutritional scientist will tell you that fat IS the primary source of fuel for the human animal.
Tell me – are you sitting down right now? If the answer is ‘Yes’ then what the heck are you mainly burning?
If you answered fat – go to the head of the class and get a gold sticker.
If you are burning mainly carbohydrate for fuel (sugar) I suggest you get along to your health practitioner because you have pre-diabetes and should get on a better nutrition plan stat!
Rana goes on to say: “For example, the carbohydrate glucose (blood sugar) is virtually the sole fuel for the human brain.”And: “Starve yourself of complex carbohydrate and see what happens to your concentration and energy.”
Notwithstanding that Paleo is a real-food (whole, natural, unprocessed) dietary paradigm, and not necessarily restrictive of carbohydrates, Rana makes the common mistaken assumption (based probably on an incomplete undergraduate level understanding of human metabolism) that neurons rely on carbohydrate for fuel, when it is widely known that they can subsist VERY happily on ketone bodies and short-chain and medium-chain fatty acids. In fact ketone bodies such as beta-hydroxy butyrate (BOHB) provide more fuel (adenosine triphosphate (ATP) – our cellular fuel) for neurons, than glucose (Manninen, 2004). It has also been demonstrated that insulin induced hypoglycaemic coma can be reversed by intravenous administration of BOHB (Thurston, Hauhart, & Schiro, 1986) and that BOHB preserves synaptic function even in the presence of glucose deprivation and reduction of glycolysis (Izumi, Ishii, Katsuki, Benz, & Zorumski, 1998).
In short – the brain doesn’t need you to be guzzling down carbs as a) it does quite well without them thank you very much and b) endogenous requirement is more than facilitated by endogenous production.
So why would there in Rana’s words be “a lot of hallucinogenic Neanderthals roaming the earth.” [in the presence of low carb intake].
Well…there wouldn’t be…because ketosis is a state of human metabolism that is both safe and appropriate physiologically and evolutionarily. Lest we forget that there is no essential requirement for carbohydrate to be ingested by the human animal (Westman, 2002)…
But of course we don’t actually need to go there and give Pete a lesson in biochemistry because as previously mentioned Paleo is not necessarily carb-restrictive!
Rana lists several points in respect to Paleo:
• Nutritional completeness is the key factor. Any diet that short changes fruit, vegetables or wholegrains is suspect. The U.S. News & World Report's experts said the Paleo diet was too restrictive for most people to follow long term and that it limited some essential nutrients. That's because the regime excludes dairy, grains and legumes. "It's one of the few diets that experts considered somewhat unsafe" the report says.
This again shows Rana’s misunderstanding of Paleo. Paleo focuses on natural, whole and unprocessed foods and so incorporates fruits, berries, tubers and LOTS of vegetables. Sure – it limits or excludes (depending on one’s interpretation of Paleo) grains (big deal) and legumes. But for any ‘expert’ to say that a diet that encourages one to eat large amounts of vegetables, berries, nuts, seeds, free-range meats and undenatured oils is ‘unsafe’ is simply ridiculous. And the suggestion that it’s lacking in nutrients is also unfounded and lacking scientific credibility.
• Giving credit where credit's due, the Paleo diet on the surface sounds like a good idea by consuming very lean, pure meats and lots of wild plants. However encompassing such a regime in modern times would take a lot of discipline, as well as take the enjoyment out of eating.
It has been demonstrated that contrary to popular belief lower-carbohydrate and ‘Paleo’ style diets have higher compliance rates than typical low-fat, high-carbohydrate, calorie restrictive nutrition plans, with similar or greater results for fat loss (Bueno, de Melo, de Oliveira, & da Rocha Ataide, 2013; Sondike, Copperman, & Jacobson, 2003; Volek, Quann, & Forsythe, 2010; Yancy, Olsen, Guyton, Bakst, & Westman, 2004).
• The Paleo diet glycemic index argument is misleading when talking about bread and link to grains. Remember, the type of bread you eat and level of refinement of the ingredients has an impact on the GI of the bread. The fact is, wholegrains rather than processed grains can prevent big rises and drops in glucose and insulin. So there is no reason to throw the baby out with the bath water and eliminate grains altogether.
This is also a technical falsehood. The insulin response of a food is not necessarily proportionate to its glycaemic response, as first demonstrated by Holt and colleagues back in the 90’s (Holt, Miller, & Petocz, 1997). More importantly the glycaemic load provided by foods (of which grains are a primary culprit) is more of a consideration in these modern days of rampant metabolic disorder.
Rana finishes by proclaiming his love of the Mediterranean Diet: “My favourite, the Mediterranean diet is more or less how I eat. The report says it "may include weight loss, heart and brain health, cancer prevention, and diabetes prevention and control".
While gushing over the Mediterranean Diet the authors of the report and Rana may be interested to know that the ‘dangerous’ diet they are lambasting has been demonstrated to reduce blood pressure, average insulin, average glucose, total cholesterol, LDL cholesterol and triglycerides, whilst improving HDL cholesterol and anthropometric markers of diabetes and obesity (Frassetto, Schloetter, Mietus-Synder, Morris, & Sebastian, 2009; Jonsson et al., 2009)…oh and it’s probably more satiating than a Mediterranean Diet too (Jonsson, Granfeldt, Erlanson-Albertsson, Ahren, & Lindeberg, 2010)…
Now I’m not here to be a defender of Paleo diets. When people ask if I’m ‘Paleo’ I say: “Hell no – I’m not caveman…I’m a spaceman!” But I do think it’s disingenuous to lambast something that on the whole is a positive and health promoting diet without even a minimal understanding of what it is, nor the science underpinning it.
Bueno, N. B., de Melo, I. S. V., de Oliveira, S. L., & da Rocha Ataide, T. (2013). Very-low-carbohydrate ketogenic diet v. low-fat diet for long-term weight loss: a meta-analysis of randomised controlled trials. British Journal of Nutrition, 110(07), 1178-1187. doi: doi:10.1017/S0007114513000548
Frassetto, L. A., Schloetter, M., Mietus-Synder, M., Morris, R. C., Jr., & Sebastian, A. (2009). Metabolic and physiologic improvements from consuming a paleolithic, hunter-gatherer type diet. Eur J Clin Nutr, 63(8), 947-955.
Holt, S., Miller, J., & Petocz, P. (1997). An insulin index of foods: the insulin demand generated by 1000-kJ portions of common foods. The American journal of clinical nutrition, 66(5), 1264-1276.
Izumi, Y., Ishii, K., Katsuki, H., Benz, A. M., & Zorumski, C. F. (1998). beta-Hydroxybutyrate fuels synaptic function during development. Histological and physiological evidence in rat hippocampal slices. J Clin Invest, 101(5), 1121-1132. doi: 10.1172/jci1009
Jonsson, T., Granfeldt, Y., Ahren, B., Branell, U. C., Palsson, G., Hansson, A., . . . Lindeberg, S. (2009). Beneficial effects of a Paleolithic diet on cardiovascular risk factors in type 2 diabetes: a randomized cross-over pilot study. Cardiovasc Diabetol, 8, 35. doi: 10.1186/1475-2840-8-35
Jonsson, T., Granfeldt, Y., Erlanson-Albertsson, C., Ahren, B., & Lindeberg, S. (2010). A paleolithic diet is more satiating per calorie than a mediterranean-like diet in individuals with ischemic heart disease. Nutr Metab (Lond), 7, 85. doi: 10.1186/1743-7075-7-85
Manninen, A. (2004). Metabolic Effects of the Very-Low-Carbohydrate Diets: Misunderstood "Villains" of Human Metabolism. Journal of the International Society of Sports Nutrition, 1(2), 1-5. doi: 10.1186/1550-2783-1-2-7
Sondike, S. B., Copperman, N., & Jacobson, M. S. (2003). Effects of a low-carbohydrate diet on weight loss and cardiovascular risk factor in overweight adolescents. The Journal of pediatrics, 142(3), 253-258.
Thurston, J. H., Hauhart, R. E., & Schiro, J. A. (1986). Beta-hydroxybutyrate reverses insulin-induced hypoglycemic coma in suckling-weanling mice despite low blood and brain glucose levels. Metab Brain Dis, 1(1), 63-82.
Volek, J. S., Quann, E. E., & Forsythe, C. E. (2010). Low-Carbohydrate Diets Promote a More Favorable Body Composition Than Low-Fat Diets. Strength and Conditioning Journal, 32(1), 42-47.
Westman, E. C. (2002). Is dietary carbohydrate essential for human nutrition? The American journal of clinical nutrition, 75(5), 951-953.
Yancy, W. S., Jr., Olsen, M. K., Guyton, J. R., Bakst, R. P., & Westman, E. C. (2004). A Low-Carbohydrate, Ketogenic Diet versus a Low-Fat Diet To Treat Obesity and Hyperlipidemia: A Randomized, Controlled Trial. Annals of Internal Medicine, 140(10), 769-777.