By-Nutrition Expert:Meena Ganagani,Practicing Clinical Nutritionist,Mumbai.
“Folate is the natural form of vitamin B9 in food, while folic acid is a synthetic form“
The Immune System
As humans age, the risk and severity of infections vary in line with immune competence according to how the immune system develops, matures, and declines. Several factors influence the immune system and its competence, including nutrition.
The immune system evolves from the immature and developing immune responses in infants and children, through to immune function that is potentially optimal in adolescents and young adults, followed by a gradual decline in immunity in older people.
Optimal immune function is dependent on a healthy immune system. In turn, adequate nutrition is crucial to ensure a good supply of the energy sources, macro-nutrients and micro-nutrients required for the development, maintenance and expression of the immune response.(1)
Micro-nutrients for a Healthy Immune System
Micro-nutrient deficiencies are a recognized global public health issue, and poor nutritional status predisposes to certain infections. Immune function may be improved by restoring deficient micro-nutrients to recommended levels, thereby increasing resistance to infection and supporting faster recovery when infected. Diet alone may be insufficient and tailored micronutrient supplementation based on specific age-related needs are necessary. (1)
Role of Folic Acid in Immunity
Folic acid is a water-soluble B vitamin that helps the body make healthy new cells. Human body needs folic acid, especially those women who may get pregnant. Getting enough folic acid before and during pregnancy may prevent major birth defects of baby’s brain or spine. It is also known as vitamin B9, folate, or folic acid. All B vitamins help the body to convert the food (carbohydrates) into fuel (glucose), which is used to produce energy. These B vitamins often referred to as B complex vitamins, help the body use fats and protein. B complex vitamins are needed for healthy skin, hair, eyes, and liver. Also, they help the nervous system function properly. Folic acid is the synthetic form of B9 which is found in supplements and fortified foods, while folate occurs naturally in foods.
Folic acid has a vital role in human body, cell growth, and development through many reactions and processes that occur inside it, including histidine cycle, serine and glycine cycle, methionine cycle, thymidylate cycle, and purine cycle. Since the body becomes deficient in folic acid, all cycles will become ineffective and lead to many problems such as megaloblastic anemia, cancer, and neural tube defects.(2)
Folic Acid (Folate) Deficiency
The consequences of folic acid deficiency include megaloblastic anemia with alterations in bone marrow and peripheral blood (Machlin&Hu¨ni, 1994), an increased susceptibility to cancer incidence and severity (Giovanucci&Stampfer, 1993; Woon Choi & Mason, 2000; Woon Choi et al, 2003), neural tube defects (NTD), which include congenital malformations produced during the first stages of embryonic development when the open neural tube cannot be closed during the first month of pregnancy. It has been demonstrated that folic acid administration before pregnancy reduces the prevalence of neural tube defects (spina bifida and anencephaly) even in babies born of mothers who had at least one previous child with this defect (Medical Research Council, 1991; Czeizel, 1995; CDC-OPS, 2001).
Another consequence of folic acid deficiency is its role in the development of cardiovascular disease. Folic acid deficiency produces an increase of serum homocysteine levels, which results in alterations on the vascular endothelium, platelets, coagulation system and vascular reactivity (Brattstro¨m&Wilcken, 2000; McKinley et al, 2001; Stipanuk, 2001).(3)
Since 1998, the FDA has required food manufacturers to add folic acid to breads, cereals, flours, cornmeal, pastas, rice, and other grains. For other foods, check the Nutrition Facts label on the package to see if it has folic acid. The label will also tell you how much folic acid is in each serving. The label may say “folate” instead of folic acid. (4)
How to overcome folic acid deficiency?
Folic acid deficiency is an easily treatable nutritional deficiency, but if left untreated, it can lead to multiple serious complications. Folic acid deficiency is a public health issue, and the education of the public is vital. In most cases, dietary counseling can prevent the development of deficiency and supplementing folic acid to high-risk individuals. (5)
Recommended Dietary Allowances (RDAs) for Folic Acid
|Age||Dietary Folate (mcg/d)|
|Infants 0-12 months*||25 mcg|
|Children’s(1-3 years)||80 mcg|
|Children’s(4-6 years)||100 mcg|
|Children’s(7-9 years)||120 mcg|
|Boys(10–12 years)||140 mcg|
|Girls(10-12 years)||140 mcg|
|Boys(13-15 years)||150 mcg|
|Girls(13-17 years)||150 mcg|
|Boys(16-17 years)||200 mcg|
|Girls(16-17 years)||200 mcg|
|Pregnant Women||500 mcg|
|Lactating Women(0-12 months)||300 mcg|
Source: Nutrient Requirements and Recommended Dietary Allowances for Indians (ICMR 2010)
*Folic Acid: 1 mcg = 1.7 DFE (Dietary Folate Equivalent)
Sources of Folate
Folate is naturally present in a wide variety of foods, including vegetables (especially dark green leafy vegetables), fruits and fruit juices, nuts, beans, peas, seafood, eggs, dairy products, meat, poultry, and grains. Spinach, liver, asparagus, and brussels sprouts are among the foods with the highest folate levels. (6)