Research Highlights December

American Journal of Clinical Nutrition

• Early age at puberty onset may predispose an individual to many currently prevalent diseases, including cancer and adiposity. The objective was to investigate whether early life exposures influence the timing of puberty, as defined by both early and late markers, in healthy German girls and boys. Children who had gained weight rapidly between birth and 24 mo experienced pubertal growth spurt 4 months earlier than those who had gained weight normally. Rapid weight gain was also associated with an earlier peak height velocity. In both boys and girls, intrauterine and early postnatal growth factors appear to influence both early and later markers of puberty onset.

• Elevated serum triglyceride and low HDL-cholesterol concentrations have been reported in persons with HIV. Diet and omega-3 fatty acid supplementation dramatically reduced serum triglycerides, decreased arachidonic acid in the phospholipids fraction, and appeared to decrease the de novo lipogenesis associated with the metabolic syndrome in the intervention group.

• Low vitamin B-12 is associated with more pronounced metabolic evidence of vitamin B-12 deficiency when folate is elevated than when folate is not elevated. These data should be considered when assessing the potential costs, risks, and benefits of folic acid and vitamin B-12 fortification programs.

• The 12-year incidence of central geographic atrophy and age-related macular degeneration in participants at moderate-to-high risk of these outcomes was lowest for those reporting the highest consumption of omega-3 fatty acids. These results may guide the development of low-cost and easily implemented preventive interventions for progression to advanced AMD.

• The consumption of a diet consistent with the principles of the Mediterranean-style diet may protect against metabolic syndrome in Americans.

• A more frequent consumption of green tea was associated with a lower prevalence of depressive symptoms in the community-dwelling older population.

• A small positive effect of protein supplementation on lumbar spine BMD in randomized placebo-controlled trials supports the positive association between protein intake and bone health found in cross-sectional surveys. Therefore, while there is a small benefit of protein on bone health, the benefit may not necessarily translate into reduced fracture risk in the long term.

• Our results show no association between current use of multivitamins and risk of allergic disease but suggest that supplementation with multivitamins during the first years of life may reduce the risk of allergic disease at school age.

Journal Nutrition

• The microbial metabolism of dietary phytoestrogens varies considerably among individuals and influences the final exposure to bioactive compounds. In view of the increasing number of food supplements combining several classes of phytoestrogens, the microbial potential to activate various proestrogens within an individual was evaluated in 3 randomized dietary crossovers (soy, hop, and/or flax-based food supplements). The bioavailability of phytoestrogens, especially when given in mixtures, is subject to high interindividual variation. These findings support the importance of personalized screening when assessing the efficacy of such products and mixtures.

• An Inflammatory Index was developed based on the results of an extensive literature search. Results based on continuous measures of hs-CRP suggested that an increasing Inflammatory Index score (representing movement toward an antiinflammatory diet) was associated with a decrease in hs-CRP. Analyses using hs-CRP as a dichotomous variable showed that an antiinflammatory diet was associated with a decrease in the odds of an elevated hs-CRP. The results are consistent with the ability of the Inflammatory Index to predict hs-CRP and provide additional evidence that diet plays a role in the regulation of inflammation, even after careful control of a wide variety of potential confounders.
  

Journal of the American Dietetic Association

• The purpose of this pilot study was to evaluate the differences in weight control behaviors, dietary intake, and physical activity between overweight adolescents who lost weight and overweight adolescents who did not lose weight. Results showed that adolescents who lost weight were more likely to report using healthful weight control behaviors such as drinking less soda and increasing their exercise level, self-weighing, consuming diets higher in protein, and spending less time watching television compared to overweight adolescents who did not lose weight.
  
  
• Currently, little is known about the home food environment. This cross-sectional study was designed to describe the food sources of calories and key nutrients in the households of 100 families with at least one child aged 12 years or younger and compare nutrient availability to recommended levels. Participating households were food secure, ate dinner at home at least three times weekly, had parents who were married or living as domestic partners and not employed in a health-related profession, and resided in New Jersey.
  
  Protein, carbohydrate, and fat in the households supplied an average of approximately 15%, 57%, and 29% of calories, respectively. Saturated fat and total sugar accounted for an average of approximately 10% and 20%, respectively, of calories. Mean nutrient adequacy ratio for nutrients recommended to be maximized (ie, vitamins A and C, protein, dietary fiber, iron, calcium) was less than optimal, and mean ratio for those recommended to be minimized (ie, total fat, cholesterol, sodium, and sugar) exceeded recommendations.
  
  Categorization by food group revealed that the greatest availability of calories, carbohydrates, dietary fiber, total sugar, sodium, and iron was from grains. Dairy products contained the greatest quantities of saturated fat and calcium.
  

American Journal Preventive Medicine

• Menu-labeling legislation is a proposed public health intervention for poor diet and obesity that requires chain restaurants to provide nutrition information on menus and menu boards. The restaurant industry has strongly opposed menu-labeling legislation. Using scientific evidence, this paper counters industry arguments against menu labeling by demonstrating that consumers want chain restaurant nutrition information to be disclosed; the current methods of providing nutrition information are inadequate; the expense of providing nutrition information is minimal; the government has the legal right to mandate disclosure of information; consumers have the right to know nutrition information; a lack of information reduces the efficiency of a market economy; and menu labeling has the potential to make a positive public health impact.

Environmental Working Group

• Ordinary school cleaning supplies can expose children to multiple chemicals linked to asthma, cancer, and other documented health problems and to hundreds of other air contaminants that have never been tested for safety. Lax labeling requirements mean that schools often don't know what they're purchasing. Many would be alarmed to learn that when used as directed, Comet Disinfectant Powder Cleanser, a product commonly used in both schools and private homes, released more than 100 air contaminants, including chloroform, benzene, and formaldehyde. In response to these concerns, many schools have turned to safer cleaning supplies that have been independently certified to meet protective health and safety standards. Eight states have passed legislation requiring or encouraging use of these green cleaning products in schools. Many other forward-thinking school districts have adopted green cleaning policies, replacing toxic products with safer, effective alternatives with no increase in costs.