Food fortification folic acid

C Bower, NJ Wald. Vitamin B12 deficiency and the fortification of food with folic acid. Eur J Clin Nutr 49 787-793, 1995. 

Folate is the generic name used to refer to a family of vitamers with related biological activity. Instead, folic acid (pteroylglutamin acid, PGA) (Fignre 19.16) refers to the most oxidized, stable, and easily adsorbable synthetic form (monoglutamate). It is commonly nsed in food supplements and in food fortification because of its stability and becomes biologically active after redaction. 

Folacin has recently been implicated in a number of nonvitamin functions, including roles in various types of cancer, coronary heart disease, and the prevention of birth defects, such as neural tube abnormalities (109,121,131-144). Investigations into these functions are ongoing and have generated controversy concerning the exact nature of the nonvitamin functions, human nutritional requirements for folacin, and the wisdom of food fortification or supplementation of selected population groups with pharmacological doses of folic acid (131,132,145-150). 

GE Gaull, CA Testa, PR Thomas, DA Weinreich. Fortification of the food supply with folic acid to prevent neural tube defects is not yet warranted. J Nutr 126 773S-780S, 1996. 

For prevention of disease in the elderly, the pregnant, or other susceptible groups, national fortification of food with vitamin B12 appears sensible and inexpensive but at present is not used and, in the absence of population screening s unlikely to be mandated by governmental edict. In general terms, the hematological manifestations of vitamin B12 deficiency are rapidly and fully correctable, although deficiencies of other micronutrients such as iron, folic acid, pyridoxine, copper, or vitamin C may be unmasked in the process and may limit the bone marrow s response until they are also corrected. 

Supplements of folic acid (0.4 mg/day), or possibly less, can reduce the rate of NTDs. To achieve an extra 0.4 mg folic acid per day, using food, one would have to drink eight glasses of orange juice or eat three servings of Brussels sprouts per day (Wald and Bower, 1995). Since it is not likely that any population, as a whole, would be expected to consume folic acid supplements on a consistent, daily basis, food fortification has become an attractive option. Because neural tube formation occurs early in pregnancy, it is probably necessary for folic acid supplements (when taken) to be consumed for 2-3 weeks (every day) prior to the day of conception, and for 2-3 weeks (every day) after conception, in order for the vitamin to produce its apparent effect. 

Based on folate concentrations in liver biopsy samples, and assuming that the liver contains about half of ail body stores, total body stores of folate are estimated to be between 12 and 28 Kinetic studies that show both fast-turnover and very-slow-turnover folate pools indicate that about 0.5% to 1% of body stores are catabolized or excreted daily,suggesting a minimum daily requirement of between 60 and 280)Llg to replace losses. In calculating nutritional requirement, the concept of dietary folate equivalents (DFE) has been used to adjust for the nearly 50% lower bioavailabihty of food folate compared with supplemental folic acid, such that 1 p.g DFE = 0.6 Llg of folic acid from fortified food = 1 j,g of food folate 0.5 p.g foUc acid supplement taken on an empty stomach. Before the fortification program of cereal grains with folic acid conducted between 1988 and 1994, the median intake of folate from food in the United States was approximately 250p.g/day this figure is expected to increase by about 100 Llg/day after fortification. Recommendations... 

CIO. Colman, N., Larsen, J. V., Barker, M., Barker, E. A., Green, R., and Metz, J., Prevention of folate deficiency by food fortification. V. A pilot field trial of folic acid-fortified maize meal. S. Afr. Med. J. 48, 1763-1766 (1974). 

Folic Acid Fortification. U.S. Food and Drug Administration. http //vm.cfsan.fda.gov/ dms/wh folic.html (accessed on October 10, 2005). 

Chandra-Hioe, M. V, BucknaU, M. R, and Arcot, J. 2013. Folic acid-fortified flour Optimised and fast sample preparation coupled with a vahdated high-speed mass spectrometry analysis suitable for a fortification monitoring program. Food Anal. Methods. DOI 10.1007/S12161-012-9559-3. 

However large RCTs, such as VISP (Toole et al. 2004) or VITATOPS (Anonymous 2010) have failed to document any significant effects of B vitamins on stroke prevention. Post hoc analyses, such as that of HOPE-2 (Saposnik et al. 2009) have suggested that folate, Bg and B12 could reduce stroke risk in patients with known CVD, mainly if patients were younger than 70 years, recruited from regions without folic acid food fortification, with higher baseline cholesterol and Hey levels, and not under antiplatelet or lipid-lowering... 

Tucker, K.L., Mahnken, B., Wilson, P.W., Jacques, P., and Selhub, J., 1996. Folic acid fortification of the food supply. Potential benefits and risks for the elderly population. The Journal of American Medical Association. 276 1879-1885. 

Table 25.2 Applications of stable isotope dilution assays (SIDAs) to food folates. Reported SID As for foods with and without fortification with folic acid are listed along with the isotopologic standard used.

Applications of folate stable isotope dilution assays are reported for foods with or without fortification by folic acid and for clinical samples such as blood serum, plasma, red blood cells, urine and ileostomy effluents. 

Reference Intakes for folate have been reported (Food and Nutrition Board 1998) (Table 44.2). The high frequency of folate deficiency has led the Food and Drug Administration in the United States to require folic acid fortification of all enriched cereals and grain products since January 1998. Folate deficiency is a major public health concern both northern and southern countries, and affects both industrialized and non-industrialized nations. In non-industrialized countries, it is particularly accentuated by poverty, limited access to food resources, and infectious diseases (Change and Abdennebi-Najar, 2011). 

In 1992, the US Public Health Service issued a recommendation that all women capable of becoming pregnant consume 400 tg of folic acid daily to reduce the risk of having a child born with a neural tube defect (Centers for Disease Control and Prevention 1992). Food fortification was implemented to reduce the number of pregnancies affected by NTDs (Centers for Disease Control and Prevention 2005). Estimates have shown that the additional intake of folic acid through food fortification has been effective in reducing the prevalence of NTDs at birth. 

Diet supplementation or food fortification with folic acid in the periconception period allows reducing the recurrence and severity of NTDs and other adverse outcomes. 

Tumours The association between intakes of folate, vitamin Bs and vitamin B12 and the risk of colorectal cancer in women has been examined. Food fortification with folic acid for 3-9 years was associated with an increased risk... 

Milk is not a rich source of dietary folate compared to other foods however, as is the case for riboflavin, folate concentrations can be significantly increased in many dairy products due to microbial fermentation. Among dairy products, fermented milks are considered a good potential matrix for folate fortification because folate-binding proteins present in milk improve folate stability and enhance the bioavailability of both 5-methyltetrahydrofolate (the most predominant natural form of the vitamin) and folic acid (Jones and Nixon 2002 Aryana 2003 Verwei et al. 2003). However, due to the potential risks of fortification with folic acid, the elaboration of fermented milks containing elevated levels of natural folates would be a better suited alternative. 

Shrestha, A. K., Arcot, J. Paterson, J. L. (2003). Edible coating materials-their properties and use in the fortification of rice with folic acid. Food Research International, 36, 921-928. 

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