Paleo Diet: The Premises

Transcription

1 Paleo Diet: The Premises Paleolithic diet, 12 million to 12 thousand years ago is reference standard for modern humans There is a single type of paleolithic diet Genes for nutrition established by end of Paleolithic. Gene-culture nutrition mismatch. Current human diets not adapted to genes. From Eaton & Konner. NEJM 1985;312:283; Turner & Thompson, Nutr Rev 2014;71:501

2 Eaton & Konner Paleo Diet High in lean meat, fish, vegetables, fruit Low in milk, cereal grains High in protein, cholesterol, fiber, essential fatty acids High polyunsaturated to saturated fat ratio Low in sodium Low in sugar From Eaton & Konner. NEJM 1985;312:283

3 Paleo Diet: Problems in the Premise No single Paleolithic diet. Many diets, diverse in foods and major nutrients. From Turner & Thompson, Nutr Rev 2014;71:501

4 Paleo Diet: Huge Diversity Diversity among locales. Starches from wild grains, grasses, beans, seeds, tubers Fruit was major, e.g. >50%; and animal was minor, 1-25%, invertebrates -- Thailand, Late Miocene (Hamon N, Anatomical Record 2012;295:1017) Insects such as termites: could be major (McGrew, J Hum Evol 2014; Lesnik, J Hum Evol 2014) Land snails Freshwater fish and water fowl Tortoise and turtle Marine shellfish and large fish Also, Turner & Thompson, Nutr Rev 2014;71:501

5 Paleo Diet: Adaptation Large mammal populations such as wild horses, deer, ass were susceptible to climate change, population crashes. Late paleolithic humans shifted intake from large mammals to small mammals such as hares and other species such as birds and fish; and plants. Neanderthals could not do this. Competed with wolves and big carnivores. Causes for demise? Richards Trinkaus. PNAS 2001;98:6528.

6 Paleo Diet: Adaptation Diversity away from large mammals is a crucial aspect of true diets of paleolithic humans. Plants comprised 60-80% of diet. Diversity of foods correlates with cultural expression such as sculpture, textiles, elaborate burials. From Turner & Thompson, Nutr Rev 2014;71:501 El Zaatari, J Phys Antrhopol 2014.

7 Paleo Diet: Grains and flour Extensive foraging and processing of wild plants. Highly specialized tools to separate edible parts of plants such as cattails, rhizosomes, ferns, seeds, tubers. Flour was made by grinding tools and stored. Europe and China, >30,000 to 20,000 years ago. Revedin A, PNAS 2010;107: Liu L, PNAS 2013;110:5380

8 Paleo Diet: The Evidence on Health Sparse knowledge A few randomized trials, small numbers, some uncontrolled Most studies show improved risk factors Could be healthful depending on the specific diet

9 Does Eating Fat Make Us Fat? Frank Sacks, MD Professor of Cardiovascular Disease Prevention, Nutrition Department, Harvard T.H. Chan School of Public Health; Professor of Medicine, Harvard Medical School, Brigham & Women s Hospital

10 Eating Fat Makes Us Fat! Frank Sacks, MD Professor of Cardiovascular Disease Prevention, Nutrition Department, Harvard T.H. Chan School of Public Health

11 Not Eating Fat Makes Us Fat! Frank Sacks, MD Professor of Cardiovascular Disease Prevention, Nutrition Department, Harvard T.H. Chan School of Public Health

12 Eating Fat and Not Eating Fat Makes Us Fat Frank Sacks, MD Professor of Cardiovascular Disease Prevention, Nutrition Department, Harvard T.H. Chan School of Public Health

13 The KE Diet: A High-Fat, Low-Carb Diet for Weight Loss in 10 days: Tube feeding 800 kcal fat and protein per day

14 Why High-Carb for Weight Loss? Thoughts from the 1990 s Low energy density, harder to overeat High satiety of carb compared to fat Less flavor, less desire to eat a lot Metabolism of excess dietary carb to body fat is less efficient than excess dietary fat to body fat. Less fat deposition during overeating.

15 Eat More to Lose Weight? An experiment in macrobiotics

16 Strict Vegetarian Low-Fat Diets Caused Weight Loss Strict Vegetarians in Boston - 73 men, 43 women, mostly in their 20 s - Vegetarian for 3 years - Fat 22%, Carb 65%, Protein 13%, High Fiber - Whole grains; loads of vegetables - No white flour or sugar, few sweets, little fruit juice - Matched for age and sex with nearby non-vegetarians - Body weight: 128 lb (58 kg) vs 161 lb (73 kg) = a 33 pound, 15 kg difference! Sacks FM et al. N Engl J Med 1975;292:1148

17 Vegetarian Very Low-Fat Diet Caused Weight Loss 20 Coronary Disease Patients, San Francisco - Fat <10%, some meals provided - Body weight: - Baseline: 200 lb (91 kg) - After 1 year: 178 lb (81 kg) - After 5 years: 183 lb (83 kg) - Control group increased 5 lb (2 kg) - Difference = 22 pounds, 10 kg! Gould KL et al. JAMA 1995;274:894 Ornish D et al. Lancet 1990;336:129

18 It is amateurs who have one big bright beautiful idea that they can never abandon. Professionals know that they have to produce theory after theory before they are likely to hit the jackpot. Francis Crick

19 Low Fat, High-Carb Questions: Is low-fat the most effective diet to lose weight? What happens when we put it to the test in a wider population?

20 High-Fat Atkins Diet vs Low-Fat Diet for Weight Loss Stern L Samaha F. Ann Intern Med 2004;140:769

21 Atkins High-Fat Diet vs. Conventional Low-Fat Diet 0 Change in Weight (%) -4-8 P =.001 P =.02 NS Month Foster GD, et al. N Engl J Med. 2003;348:

22 Definitive Trial: Low-Carb (Atkins) vs Low-Fat Diet (N=307 randomized) No effect on lean and fat mass Foster GD et al. Ann Intern Med 2010;153:147

23 More Adverse Effects of High-Fat Atkins vs Low-Fat Foster G et al. Ann Intern Med 2010 More bad breath, constipation, dry mouth More dropouts in low-carb: 42% vs. 32% Yancy WS et al. Ann Intern Med 2004 More bad breath, constipation, headache, myalgia, rash, weakness, low sexual interest

24 High-Fat, Mediterranean-Style

25 Superiority of High-Unsaturated Fat, Mediterranean-style diet for weight loss Months McManus, Antinoro, Sacks. Int J Obesity 2001;25:

26 Sustained Weight Loss at 6 Years Best on Mediterranean Diet: Dropouts: 63/322 (20%) Shai I et al. NEJM 2012

27 PoundsLost Trial: Generic Diets These diets with target nutrient levels: 1. Low-fat (20%), average protein (15%), highest carbohydrate (65%) 2. Low-fat (20%), high protein (25%), high carbohydrate (55%) 3. High fat (40%), average protein (15%), average carbohydrate (45%) 4. High fat (40%), high protein (25%), lowest carbohydrate (35%) Similar foods used for all diets but in different proportions. All dietary approaches adhered to healthful guidelines to prevent cardiovascular disease. Sacks FM, Bray G et al. N Engl J Med Feb 26, 2009

28 PoundsLost: Primary Trial Outcome, Body Weight Change at 2 years All 811 randomized participants. Change in body weight from baseline to 2 years, kg Protein Fat Carb High-average: -0.6 (-1.6,0.4) (P=0.22) High-low: 0.04 (-0.9,1.0) (P=0.94) High Highest vs. lowest 0.6 (-0.8,1.9) (P=0.42) Low or average Sacks FM, Bray G et al. N Engl J Med Feb 26, 2009

29 POUNDS LOST Waist circumference in Completers 0 Diet Composition -1 Carbohydrate/Protein/Fat -2 (% energy) /15/20 55/25/20 45/15/40 35/25/ Months Sacks FM, Bray G et al. N Engl J Med Feb 26, 2009

30 PoundsLost Trial Target and Reported Intakes Carbohydrate/Protein/Fat Diet Type Target 6 month 2 year Low-Fat, Av-Prot 65/15/20 58/18/26 53/20/26 Low-Fat, Hi-Prot 55/25/20 53/22/26 51/21/28 Hi-Fat, Av-Prot 45/15/40 49/18/34 49/20/33 Hi-Fat, Hi-Prot 35/25/40 43/23/34 43/21/35 Sacks FM, Bray G et al. N Engl J Med Feb 26, 2009

31 PoundsLost Trial Group Session Attendance and Weight Loss at 2 years: Total Group = 0.2 kg per session attended Sacks FM, 2009.

32 Group Session Attendance and Weight Loss: Similar in each diet group Ave Prot, Low-Fat Slope = kg/session High Prot, Low-Fat Slope = kg/session Ave Prot, High-Fat Slope = kg/session High Prot, High-Fat Slope = kg/session

33 Conclusion Successful diets for weight loss can emphasize a range of fat and carb intakes. These diets can be made with foods that reduce risk of cardiovascular disease. Ongoing counseling is important to achieve and maintain weight loss for all types of diets. Successful diets for weight loss can be adapted to individual patients personal and cultural preferences to achieve long-term success.

34 The dangerous man is the one who has only one idea, because then he'll fight and die for it." Francis Crick [As quoted in The New Yorker, April 25, 2011]

35 The Prizewinners (11 December 1962, BBC If for example I had some idea, which as it turned out would be quite wrong, was going off of the tangent, Watson would tell me in no uncertain terms this was nonsense, and vice-versa. If he would have some idea I didn't like, and I would say so, this would shake his thinking about, and draw him back again. And in fact it is one of the requirements for collaborations of this sort, is you must be perfectly candid, one might almost say rude, to the person you're working with. Francis Crick speaking of his collaboration with James Watson