AJCN Oct, 2005

[best effect with 800 mg folate per day] Lynn B Bailey Do low doses of folic acid result in maximum lowering of homocysteine?
Am J Clin Nutr 2005 82: 717-718. The link between hyperhomocysteinemia and the risk of vascular disease has been the impetus for numerous controlled intervention studies, which have established the fact that folic acid has a significant homocysteine-lowering effect…This new meta-analysis provides evidence of a graded homocysteine dose response among low folic acid doses, in which the lowest 2 doses each differ from the next dose (ie, 0.2 mg versus 0.4 mg/d and 0.4 mg versus 0.8 mg/d), but there were no differences between 0.8 mg/d and the higher doses (ie, 2.0 or 5.0 mg/d). The maximum reduction (23%) in plasma homocysteine concentration was observed with 0.8 mg folic acid/d; 20% and 13% reductions were observed with the lower doses (0.4 and 0.2 mg/d).

Steven H Zeisel Choline, homocysteine, and pregnancy Am J Clin Nutr 2005 82: 719-720. – Choline is a dietary component essential for the structural integrity and signaling functions of cell membranes; it directly affects cholinergic neurotransmission and lipid transport from liver, and it is the major source of methyl groups in the diet (betaine, one of choline’s metabolites, participates in the methylation of homocysteine to form methionine) (1). In many mammals, including baboons, prolonged (weeks to months) ingestion of a diet deficient in choline but adequate, though limited, in methionine and folate has consequences that include hepatic, renal, pancreatic, memory, and growth disorders (1)…In addition, choline is particularly important during the perinatal period because it appears to change brain development.

Mark Worwood et al. Diet and genetic factors associated with iron status in middle-aged women. Am J Clin Nutr 2005 82: 813-820. Background: Gene mutations associated with iron overload have been identified…”Public health policy regarding iron is to try to prevent the occurrence of iron deficiency or overload…the emphasis has been on preventing deficiency…However, high levels of iron storage, even within the normal range, may predispose individuals to many chronic diseases, including heart disease, diabetes, and some cancers (1)…Conclusions: Postmenopausal women eating a diet rich in heme iron and who were C282Y homozygotes had the highest serum ferritin concentrations.

[exercise enough to lose weight safely so muscle is maintained]Tamara B Harris et al, Weight change and the conservation of lean mass in old age: the Health, Aging and Body Composition Study, Am J Clin Nutr 2005 82: 872-878.We observed changes in weight and body composition during a 4-y period in 2163 men (47%) and women (53%) aged 70–79 y…Conclusions: With weight change, a greater proportion of lean mass than of fat mass was conserved, but, especially in older men, significantly more lean mass was lost with weight loss than was gained with weight gain. These findings suggest that weight loss, even with regain, could accelerate sarcopenia in older adults.

[eat your fruits and vegetables and get exercise; vitamin E was not enough] Plasma carotene and a-tocopherol in relation to 10-y all-cause and cause-specific mortality in European elderly: the Survey in Europe on Nutrition and the Elderly, a Concerted Action (SENECA)
Am J Clin Nutr 2005 82: 879-886.Design: Plasma concentrations of carotene and a-tocopherol were measured in 1168 elderly men and women. After a follow-up period of 10 y, 388 persons had died. ..Plasma concentrations of a-tocopherol were not associated with all-cause or cause-specific mortality. Conclusions: This prospective study suggests that high plasma concentrations of carotene are associated both with lower mortality from all causes and with cancer in the elderly. For cardiovascular mortality, the inverse association was confined to elderly with body mass indexes <25.

[fish oil reduces dry eye syndrome] Debra A Schaumberg et al, Relation between dietary n–3 and n–6 fatty acids and clinically diagnosed dry eye syndrome in women, Am J Clin Nutr 2005 82: 887-893. A higher ratio of n–6 to n–3 FA consumption was associated with a significantly increased risk of DES (Odds Ratio: 2.51) Conclusions: These results suggest that a higher dietary intake of n–3 FAs is associated with a decreased incidence of DES in women. These findings are consistent with anecdotal clinical observations and postulated biological mechanisms.

[Dairy fat reduces colon cancer risk] Alicja Wolk et al, High-fat dairy food and conjugated linoleic acid intakes in relation to colorectal cancer incidence in the Swedish Mammography Cohort, Am J Clin Nutr 2005 82: 894-900.Each increment of 2 servings of high-fat dairy foods/d corresponded to a 13% reduction in the risk of colorectal cancer…Conclusion: These prospective data suggest that high intakes of high-fat dairy foods and CLA may reduce the risk of colorectal cancer.