“There is a general consensus in the literature that protein stimulates dietary-induced thermogenesis [burning of calories] to a greater extent than other macronutrients.” – D. Paddon-Jones, University of Texas
“Convincing evidence exists that protein exerts an increased thermic effect [calorie burning] effect when compared to fat and carbohydrate.” – T.L. Halton, Harvard University
Eating a natural amount of protein—about one gram of protein per pound of body weight per day (not exceeding 200 grams…aka if you weigh 350 lbs, don’t eat 350 grams of protein)—is critical to getting our biological functions back to normal. Why? First, high-Satiety protein fills us up and keeps us full, so we have no room for low-quality food. Second, our metabolism will burn body fat instead of muscle. As researcher D.K. Layman from the University of Illinois tells us: “Use of higher protein diets reduces lean tissue loss to less than 15% and when combined with exercise can halt loss of lean tissue during weight loss.”
Some people say that eating a gram of protein per pound of body weight hurts the kidneys and liver. This is not borne out, however, in clinical testing. For instance, A.H. Manninen at the University of Oulu concluded: “Simply stated, there is no scientific evidence whatsoever that high-protein intake has adverse effects on liver function.” T.L. Halton at Harvard University addresses the other part of the argument: “There is little evidence that high protein diets pose a serious risk to kidney function in healthy populations.”
“Seafood and poultry have been associated with lower rates of coronary heart disease and cancer.” – M.L. McCullough, American Cancer Society
On the other hand, guess how many studies show positive health benefits and body-fat loss stemming from a more balanced intake of protein? Dozens. A typical report comes from Loren Cordain at Colorado State University: “There is now a large body of experimental evidence increasingly demonstrating that a higher intake of lean animal protein reduces the risk for cardiovascular disease, hypertension, dyslipidemia, obesity, insulin resistance, and osteoporosis while not impairing kidney function.” That’s because researchers have shown that humans evolved to get about a third of our calories from protein. Dr. Cordain goes on: “So called …‘very high protein diets’ (30% – 40% total energy) actually represent the norm which conditioned the present day human genome…The evolutionary template would predict that human health and well-being will suffer when dietary intakes fall outside this range.”
“Our bodies…seem genetically constituted to accept a fairly high protein load.” – S. Boyd Eaton, Emory University
How could a basic part of human evolution harm rather than help us? Emory University researchers S. Boyd Eaton and M. Konner made the point well when they noted, “It would be paradoxical if humans…should now somehow be harmed as a result of protein intake habitually tolerated or even required by their near relatives.”
How did the myth that protein is bad for us get started in the first place? Let’s cover that in the next post.
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- Boyd, S., Melvin Konner, Marjorie Shostak, and M.D. Eaton. The Paleolithic Prescription: A Program of Diet & Exercise and a Design for Living. New York: HarperCollins, 1989. Print.
- Eaton SB, Eaton SB 3rd, Konner MJ. Paleolithic nutrition revisited: a twelve-year retrospective on its nature and implications. Eur J Clin Nutr. 1997 Apr;51(4):207-16. Review. PubMed PMID: 9104571.
- Farnsworth E, Luscombe ND, Noakes M, Wittert G, Argyiou E, Clifton PM. Effect of a high-protein, energy-restricted diet on body composition, glycemic control, and lipid concentrations in overweight and obese hyperinsulinemic men and women. Am J Clin Nutr 2003;78:31–9.
- Halton TL, Hu FB. The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review. J Am Coll Nutr. 2004 Oct;23(5):373-85. Review. PubMed PMID: 15466943.
- Layman DK, Boileau RA, Erickson DJ, et al. A reduced ratio of dietary carbohydrate to protein improves body composition and blood lipid profiles during weight loss in adult women. J Nutr 2003;133:411–7.
- Layman DK. Dietary Guidelines should reflect new understandings about adult protein needs. Nutr Metab (Lond). 2009 Mar 13;6:12. PubMed PMID: 19284668; PubMed Central PMCID: PMC2666737.
- Manninen AH. High-protein weight loss diets and purported adverse effects: where is the evidence? Sports Nutr Rev J 2004; 1: 45–51.
- Manninen, A.H. (2002) Protein metabolism in exercising humans with special reference to protein supplementation. Master thesis. Department of Physiology, Faculty of Medicine, University of Kuopio, Finland.
- McCullough ML, Feskanich D, Stampfer MJ, Giovannucci EL, Rimm EB, Hu FB, Spiegelman D, Hunter DJ, Colditz GA, Willett WC. Diet quality and major chronic disease risk in men and women: moving toward improved dietary guidance. Am J Clin Nutr. 2002 Dec;76(6):1261-71. PubMed PMID: 12450892.
- P.J. Skerrett, and W.C. Willett. Eat, Drink, and Be Healthy: The Harvard Medical School Guide to Healthy Eating. Free Press Trade Pbk. Ed ed. New York City: Free Press, 2005. Print.
- Paddon-Jones D, Westman E, Mattes RD, Wolfe RR, Astrup A, Westerterp-Plantenga M. Protein, weight management, and satiety. Am J Clin Nutr. 2008 May;87(5):1558S-1561S. Review. PubMed PMID:18469287.
- The Evolutionary Basis for the therapeutic Effects of High Protein Diets: http://cathletics.com/articles/proteinDebate.pdf
- Westerterp-Plantenga MS. Protein intake and energy balance. Regul Pept. 2008 Aug 7;149(1-3):67-9. Epub 2008 Mar 25. Review. PubMed PMID: 18448177.
- Wolfe BM, Piché LA. Replacement of carbohydrate by protein in a conventional-fat diet reduces cholesterol and triglyceride concentrations in healthy normolipidemic subjects. Clin Invest Med. 1999 Aug;22(4):140-8. PubMedPMID: 10497712.
- Wolfe RR. The underappreciated role of muscle in health and disease. Am J Clin Nutr. 2006 Sep;84(3):475-82. Review. PubMed PMID: 16960159.
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