AJCN June, 2005

James O Hill Obesity treatment: does one size fit all? Am J Clin Nutr 2005 81: 1253-1254

Those trying to lose weight are quick to embrace the latest popular diet but are almost as quick to abandon it…Several randomized controlled studies have shown that these diets are effective in producing weight loss and metabolic improvements over 6 mo in obese patients (1-5)…Because low-fat and low-carbohydrate diets have already been popular choices, one good possibility is that a high-protein diet will be the next popular diet (6)…Two important messages emerged from this study. First, Noakes et al found that the hypocaloric HP diet produced weight loss comparable to that of the HC diet and provided nutritional and metabolic benefits that were equal to or in some cases greater than those seen with the HC diet. Second, in a post hoc analysis, they found that obese subjects in the top 50% of blood triacylglycerol concentrations at baseline lost more weight with the hypocaloric HP diet than with the hypocaloric HC diet. Thus, the study is noteworthy in that it suggests that high-protein diets are effective at both producing weight loss and improving risk factors for diabetes and heart disease and that it may be possible to identify persons who do particularly well with high-protein diets… It may be useful to consider weight management as consisting of 2 different phases: achieving weight loss and maintaining weight loss. The strategies that work for losing weight may not be effective for keeping weight off. We have found this to be the case in a review of the National Weight Control Registry, which follows 5000 people who have succeeded in maintaining weight loss in the long term (8). When it comes to choosing a hypocaloric diet, one size may not fit all. However, keeping weight off requires the achievement of a permanent balance between energy intake and energy expenditure. Here is where physical activity becomes critically important (8) and may even be more important than diet composition.

Janis S Fisler and Craig H Warden Dietary fat and genotype: toward individualized prescriptions for lifestyle changes Am J Clin Nutr 2005 81: 1255-1256

Nutritional genomics (or nutrigenomics) is the newly developing science of how a person’s diet interacts with his or her genotype to influence the balance between health and disease (1, 2). ..In examining the effects of the –514CT LIPC polymorphism x dietary fat interaction on HDL in 2130 men and women participating in the Framingham Study, Ordovas et al (6) found that the rarer TT genotype was associated with significantly higher HDL-cholesterol concentrations only in subjects consuming <30% of energy from fat.

PK Newby, Katherine L Tucker, and Alicja Wolk Risk of overweight and obesity among semivegetarian, lactovegetarian, and vegan women Am J Clin Nutr 2005 81: 1267-1274.

Results: The prevalence of overweight or obesity (BMI 25) was 40% among omnivores, 29% among both semivegetarians and vegans, and 25% among lactovegetarians…Conclusions: Even if vegetarians consume some animal products, our results suggest that self-identified semivegetarian, lactovegetarian, and vegan women have a lower risk of overweight and obesity than do omnivorous women. The advice to consume more plant foods and less animal products may help individuals control their weight.

Charalambos Vlachopoulos, et al Chronic coffee consumption has a detrimental effect on aortic stiffness and wave reflections Am J Clin Nutr 2005 81: 1307-1312.

Conclusions: Chronic coffee consumption exerts a detrimental effect on aortic stiffness and wave reflections, which may increase the risk of cardiovascular disease. [Study compared drinking no coffee vs. 1 cup a day vs. 2 cups a day vs. more than that. Impact on blood pressure went from 3.4 to 7.7 to 8.0 mm Hg, which was the maximum even for those exceeding 2 cups a day.]

Mandi J Bossingham, Nadine S Carnell, and Wayne W Campbell Water balance, hydration status, and fat-free mass hydration in younger and older adults Am J Clin Nutr 2005 81: 1342-1350

Conclusions: These results show that healthy older adults maintain water input, output, and balance comparable to those of younger adults and have no apparent changes in hydration status. [ed. notes: median water intake from all sources was 3.7L/day for men and 2.7L/day for women. A 2% loss of water from the body will negatively affect exercise performance!]

Theresa O Scholl, Maria Leskiw, Xinhua Chen, Melissa Sims, and T Peter Stein Oxidative stress, diet, and the etiology of preeclampsia Am J Clin Nutr 2005 81: 1390-1396

Conclusions: Increased urinary excretion of isoprostane and decreased antioxidant production is an imbalance that is consistent with oxidative stress, and it precedes clinical recognition of preeclampsia. The maternal diet is an underlying factor that provides an environment for free radical generation.

Chung-Jung Chiu et al, Carbohydrate intake and glycemic index in relation to the odds of early cortical and nuclear lens opacities, Am J Clin Nutr 2005 81: 1411-1416.

…the odds of cortical opacities among women in the highest tertile of carbohydrate intake (200 g/d) was 2.46 times that among women in the lowest tertile…Conclusions: These data suggest that carbohydrate quantity, but not carbohydrate quality, is associated with early cortical opacities, and that neither the quantity nor the quality of dietary carbohydrate affects the risk of nuclear opacities in middle-aged women.