AJCN Feb, 2009 – The February American Journal of Clinical Nutrition …
SUMMARY –AJCN Feb, 2009 – The February American Journal of Clinical Nutrition-lots to digest! Read the full stories with links at http://www.beloit.edu/nutrition/ln/ln09febajcn.
1. IS MATERNAL SUPPLEMENTATION BENEFICIAL? Papers presented at this symposium consider 3 specific nutrients: methyl donors folate and choline, iodine, and docosahexaenoic acid (DHA; 22:6n–3), all nutrients for which there is new evidence for increased dietary importance during pregnancy and lactation and all of which are important for neurodevelopment of the fetus and infant. Requirements increase for 14 of 21 essential micronutrients during pregnancy In 2000, about 48% of men and 57% of women took some form of supplements. In 2005, annual expenditures in the US were about $15 billion.
2. IS IT TIME FOR VITAMIN B12 FORTIFICATION? About 20% of people in the US and Britain have marginal vitamin B12 status. Such women had three times the risk of bearing children with neural tube defects. Risk of cognitive impairment in elderly doubles.
Enjoy soy, fish oil, and vitamin E:
3. Soy intake reduces postmenopausal colorectal cancer
4. Vitamin E reduces pancreatic cancer risk about 50%.
5. Fish oil derivative alleviates moderate to severe depression
Helping reduce obesity, blood pressure, and cognitive decline
6. Small changes in diet and exercise can reduce obesity
7. Parental obesity strongly influences children’s obesity
8. Reducing dietary salt intake may lower blood pressure[Although there is evidence supporting both sides of the relationship between dietary salt and blood pressure, this study of 29 obese men did find that lowering salt INTAKE lowered blood pressure]
9. Very high or low weight lowers cognitive function when older
OTHER NEWS
10. Prevalence of iron deficiency is low (3%) among breastfed infants. Iron deficiency during infancy is common in the developing world
11. For type I diabetics, high fat, low sugar diet causes poorer control of blood sugar levels
DETAILS –
1. SUPPLEMENT: IS MATERNAL SUPPLEMENTATION BENEFICIAL? Table of contents at bottom
Introduction – Human data that support the requirement for specific nutrients during pregnancy and lactation are limited beyond the need to avoid overt deficiency diseases, even though suboptimal intakes of nutrients are likely to be much more common than observed…papers presented at this symposium consider 3 specific nutrients: methyl donors, iodine, and docosahexaenoic acid (DHA; 22:6n–3), all nutrients for which there is new evidence for increased dietary importance during pregnancy and lactation and all of which are important for neurodevelopment of the fetus and infant. ..Although the current recommended intake for folic acid intake for women of childbearing age to prevent neural tube defects is 400 µg/d, new recommendations are expected soon from the US Preventive Services Task Force. ..This is particularly important, given the new recommendations of the American Thyroid Society (6) to supplement all pregnant women living in the United States or Canada with 150 µg iodine. ..the number of observational studies linking higher DHA status to favorable infant developmental outcomes increases the need for more experimental trials…The potential benefits to the fetus and infant of DHA supplements for pregnant or lactating women are suggested largely by randomized controlled studies in which supplements were given orally to infants after birth. Because it appears that preterm infants may benefit most from DHA-supplemented formula after birth, one wonders about the impact of feeding a preterm infant the mother’s breastmilk in the absence of maternal or infant DHA supplements…
Requirements increase for 14 of 21 essential micronutrients during pregnancy – Although there exist some recommendations concerning the need for a limited number of nutrients in supplemental form (eg, iron, folic acid, and iodine), there is a relative paucity of data concerning the use of dietary supplements during pregnancy and lactation. ..recommended intakes for 14 of the 21 essential micronutrients increase during pregnancy. These nutrients comprise 7 vitamins, 5 minerals, and choline (Allen, LH. Pregnancy and lactation. In: , Bowman, BA & Russell, RM, eds. Present knowledge in nutrition. 9th ed. Vol 2. Washington, DC: International Life Sciences Institute, 2006, 529–43). [In 2000, about 48% of men and 57% of women took some form of supplements. In 2005, annual expenditures in the US were about $15 billion.]
Folate and choline during reproduction – Evidence is growing that optimal dietary intake of folate and choline (both involved in one-carbon transfer or methylation) is important for successful completion of fetal development. Significant portions of the population are eating diets low in one or both of these nutrients. Folates are important for normal neural tube closure in early gestation, and the efficacy of diet fortification with folic acid in reducing the incidence of neural tube defects is a major success story for public health nutrition. Similarly, maternal dietary choline is important for normal neural tube closure in the fetus and, later in gestation, for neurogenesis in the fetal hippocampus, with effects on memory that persist in adult offspring; higher choline intake is associated with enhanced memory performance.
DHA during pregnancy – few clinical studies show benefits of maternal DHA supplementation during pregnancy or lactation for the infant or child. However, quite a large number of observational studies link higher intrauterine DHA exposure to a number of positive developmental outcomes.
2. SUPPLEMENT: IS IT TIME FOR VITAMIN B12 FORTIFICATION? Table of contents at bottom
About 20% of people in the US and Britain have marginal vitamin B12 status. Women with low vitamin B12 had three times the risk of bearing children with neural tube defects. Risk of cognitive impairment in elderly doubles with B12 deficiency.
3. Soy intake reduces postmenopausal colorectal cancer – Each 5-g/d increment in intake of soy foods as assessed by dry weight [equivalent to 1 oz tofu/d] was associated with an 8% reduction in risk…Conclusion: This prospective study suggests that consumption of soy foods may reduce the risk of colorectal cancer in postmenopausal women.
4. Vitamin E reduces pancreatic cancer risk – Results: Higher {alpha}-tocopherol concentrations were associated with [about 50%] lower pancreatic cancer risk…Our results support the hypothesis that higher {alpha}-tocopherol concentrations may play a protective role in pancreatic carcinogenesis in male smokers.
5. Fish oil derivative for depression – Background: Psychological distress (PD) and depressive symptoms are commonly observed during menopausal transition. Studies suggest that omega-3 (n–3) fatty acids may help alleviate depression…Design: Women with moderate-to-severe PD (n = 120) were randomly assigned to receive 1.05 g E-EPA/d plus 0.15 g ethyl-docosahexaenoic acid/d (n = 59) or placebo (n = 61) for 8 wk…Conclusions: To our knowledge, this is the first trial of n–3 supplementation in the treatment of PD and depressive symptoms in middle-aged women. In women with PD without MDE at baseline, the 8-wk changes in PD and depressive scales improved significantly more with E-EPA than with placebo. This trial was registered at http://www.controlled-trials.com as ISRCTN69617477.
6. Small changes in diet and exercise can reduce obesity – The continued rise in obesity rates in most countries suggests that current programs and initiatives designed to combat obesity have not been successful in reversing the obesity epidemic…An alternative strategy to address the obesity epidemic involves not focusing on weight loss but promoting small changes in diet and physical activity to initially prevent further weight gain…Such an initiative would benefit from the support of educational and social marketing campaigns developed with governmental input and support.
7. Parental obesity strongly influences children’s obesity – Parental obesity in adulthood is a strong determinant of offspring obesity. ..Excessive BMI gains of parents during childhood and adulthood were associated with a higher BMI and risk of obesity in the offspring. Reductions in the incidence of child obesity in the current population may reduce obesity in future generations.
8. Reducing dietary salt intake may lower blood pressure – [Although there is evidence supporting both sides of the relationship between dietary salt and blood pressure, this study of 29 obese men did find that lowering salt lowered blood pressure.] Conclusions: Salt reduction improves endothelium-dependant vasodilation in normotensive subjects independently of the changes in measured resting clinic blood pressure.
9. Very high or low weight lowers cognitive function when older – Conclusions: Long-term obesity and long-term underweight in adulthood are associated with lower cognitive scores in late midlife. Public health messages should promote a healthy weight at all ages.
10. Prevalence of iron deficiency is low (3%) among breastfed infants during first 6 months of life in industrialized nations. Iron deficiency during infancy common in developing world – Iron deficiency affects millions of children worldwide. As a pediatric hematology-oncology specialist practicing in a large metropolitan area, I encounter iron deficiency anemia far more often than I should. In fact, it is the most common diagnosis in our hematology referral practice. Iron deficiency during infancy and early childhood should be preventable by means of breastfeeding, iron supplementation in breastfed infants >6 mo of age, iron-fortified formula during the first year of life as an alternative to breastfeeding, and avoidance of excessive whole cow milk intake later in infancy (1). One of the many failures of our primary health care system is that this condition remains so prevalent in most communities in the United States…Human breast milk contains only minute quantities (<1 mg/L) of iron but up to 50% of it is absorbed. It is generally accepted that iron intake in exclusively breastfed infants is adequate during the first 6 mo of life because of an infant’s ability to reutilize the abundant iron derived from senescent erythrocytes. Only at {approx}5 to 6 mo of age, when the infant is rapidly growing and outstrips his or her iron endowment from birth, is supplemental iron recommended in the form of iron-fortified formula, iron-fortified cereals, iron drops, or other iron-containing foods.
11. For type I diabetics, high fat, low sugar diet causes poorer control of blood sugar levels – Background: Persons with type 1 diabetes have received widely varying dietary advice based on putative effects on glycemic control…Conclusion: Among intensively treated patients with type 1 diabetes, diets higher in fat and saturated fat and lower in carbohydrate are associated with worse glycemic control, independent of exercise and BMI.
