Recent Studies on Folic Acid
Folic Acid has a protective effect upon unborn babies
Britain's Medical Research Council 'Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group' The Lancet, 1991.
A randomised double-blind prevention trial with a factorial design was conducted at 33 centres in seven countries to determine whether supplementation with folic acid (one of the vitamins in the B group) or a mixture of seven other vitamins (A,D,B1,B2,B6,C and nicotinamide) around the time of conception can prevent neural tube defects (anencephaly, spina bifida, encephalocele).
A total of 1817 women at high risk of having a pregnancy with a neural tube defect, because of a previous affected pregnancy, were allocated at random to one of four groups--namely, folic acid, other vitamins, both, or neither.
1195 had a completed pregnancy in which the fetus or infant was known to have or not have a neural tube defect; 27 of these had a known neural tube defect, 6 in the folic acid groups and 21 in the two other groups, a 72% protective effect (relative risk 0.28, 95% confidence interval 0.12-0.71). The other vitamins showed no significant protective effect (relative risk 0.80, 95% Cl 0.32-1.72). There was no demonstrable harm from the folic acid supplementation, though the ability of the study to detect rare or slight adverse effects was limited.
Folic acid supplementation starting before pregnancy can now be firmly recommended for all women who have had an affected pregnancy, and public health measures should be taken to ensure that the diet of all women who may bear children contains an adequate amount of folic acid.
New England Journal of Medicine, 'Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation', Czeizel AE, Dudás I, 1992.
Background: The risk of recurrent neural-tube defects is decreased in women who take folic acid or multivitamins containing such during the periconceptional period. The extent to which folic acid supplementation can reduce the first occurrence of defects is not known.
Methods: We conducted a randomized, controlled trial of periconceptional multivitamin supplementation to test the efficacy of this treatment in reducing the incidence of a first occurrence of neural-tube defects. Women planning a pregnancy (in most cases their first) were randomly assigned to receive a single tablet of a vitamin supplement (containing 12 vitamins, including 0.8 mg of folic acid; 4 minerals; and 3 trace elements) or a trace-element supplement (containing copper, manganese, zinc, and a very low dose of vitamin C) daily for at least one month before conception and until the date of the second missed menstrual period or later.
Results: Pregnancy was confirmed in 4753 women. The outcome of the pregnancy (whether the fetus or infant had a neural-tube defect or congenital malformation) was known in 2104 women who received the vitamin supplement and in 2052 who received the trace-element supplement.
Congenital malformations were significantly more prevalent in the group receiving the trace-element supplement than in the vitamin-supplement group. There were six cases of neural-tube defects in the group receiving the trace-element supplement, as compared with none in the vitamin-supplement group. The prevalence of cleft lip with or without cleft palate was not reduced by periconceptional vitamin supplementation.
Conclusions: Periconceptional vitamin use decreases the incidence of a first occurrence of neural-tube defects.
The Council for Responsible Nutrition (CRN) States:
Nutrition experts at the Harvard School of Public Health have created an online version of a food pyramid with a notation recommending a "daily multivitamin plus extra vitamin D (for most people)."
Recognizing the special nutritional needs of senior citizens, researchers at Tufts University designed a food guide pyramid for the elderly, which features a flag at the top as a reminder that supplements of calcium, vitamin D, and vitamin B-12 may be needed for optimal health. The American Academy of Nutrition and Dietetics (formerly the American Dietetic Association) has a policy statement emphasizing the importance of good food choices but also recognizing that supplements can help some people meet their nutritional needs.
Supplement use should be seen as one component of the search for a healthier lifestyle, including improvements in overall food habits and engaging in physical exercise.
A generous intake of calcium plus vitamin D demonstrably helps build optimum bone mass during childhood and adolescence and also slows the rate of bone loss that naturally occurs with ageing.
Nutritional supplements are helpful in addressing a woman's increased nutrient needs during pregnancy. Prenatal multivitamins with minerals are commonly prescribed to ensure that both the baby's and the mother's needs are met. In addition to meeting normal nutritional needs during pregnancy, a multivitamin can also play a critical role in protecting against some birth defects. An abundance of data shows that women who get 400 mcg of supplemental folic acid per day for one to three months prior to conception and one to three months after conception can substantially lower the risk of having a baby with a neural tube defect such as spina bifida.
While adequate nutrient intake is critical for all age groups, it may have particular significance for the elderly. Calcium and vitamin D supplements, as previously noted, can have a powerful impact on bone health, and the Surgeon General says it is never too late to benefit from improved intakes of these nutrients. Vitamin D may also reduce the incidence of falls in older people. Vitamin and mineral supplements have been shown in some studies to improve immune functionin the elderly.
Low zinc intakes are associated with an increased risk of infections, including pneumonia. Supplemental intakes of vitamin E have had a positive effect in decreasing upper respiratory infections in some studies. For these reasons, it makes sense to encourage the elderly to use multivitamin and mineral supplements.
The bottom line is that a healthy lifestyle must include a focus on dietary improvement. Generous intakes of the essential nutrients will support the normal functioning of the body and enhance health in a myriad of ways. The rational use of nutritional supplements, combined with a healthy diet, will contribute substantially to health promotion and disease prevention.