B₁ - Thiamine

Your body uses thiamine to release energy from the food you eat and to help maintain normal appetite and digestive functions. The recommended amount during pregnancy is 1.4 mg. Thiamine is found in legumes (such ad dried beans or peas), and in while grain or enriched products such as breads and cereals.

Thiamine is very unstable in an alkaline medium; the thiamine content of legumes , e.g., is largely destroyed if soda is added to the cooking water. Thiamine is present in the outer layer (or bran) of the seed or grain. Many milling processes destroy this layer; whole grain or enriched breads and cereals can make significant contribution to your diet. Extreme deficiency of thiamine is recognized clinically as beriberi, a disease characterized by abnormal muscle tone.

B₂ - Riboflavin

Riboflavin is found abundantly in liver and leafy vegetables and also in milk products. During pregnancy the recommended amount of Riboflavin is 1.4 mg. Riboflavin is relatively stable during cooking, but is destroyed by exposure to light. This fact has been a major reason for the use of paper cartons in the packaging of milk. Milk in glass bottles left in direct light exposure for two hours may lose up to 60 percent of its riboflavin content. Riboflavin plays a major role in the utilization of food energy by your body. Since is involved with energy metabolism, the amount required increases as total calorie intake increases. It is widely distributed throughout the body so deficiency of vitamin B2 will affect many different tissues. Deficiency symptoms are not frequently seen, probably because this nutrient is widely available in foods and because individual requirements can vary greatly. In the typical diet, 45 percent of the riboflavin intake is furnished by dairy products. If you do not eat these sources, care should be taken to include other sources.

B₃ - Niacin

Niacin is known as vitamin B3. Its role in the body is much like that of thiamine and riboflavin; it is a coenzyme (or component) during the chemical reactions which release energy in your body. Lack of niacin, however produces a specific condition called pellagra. Pellagra is an Italian word means “Rough skin,” and aptly describes the red rash which appears first on the hands, face and feet when they are exposed to sunlight. Untreated, intestinal problems and mental disturbance may result. Because niacin can be synthesized by bacteria in intestines and can also be formed from the amino acid tryptophan, the actual requirement is difficult to calculate. Current value of niacin for a pregnant woman is 18 mg. Niacin content of foods is not significantly affected by most cooking and storage techniques.

B₆ - Pyridoxine

The recommended amount of vitamin B6 ( also called pyridoxine) for the pregnant woman is currently 1.9 mg. or about 0.6 more than recommended for the non-pregnant woman. Just how much you and your fetus actually need is not exactly known. There is evidence that some pregnant women on normal diet show chemical changes commonly associated with vitamin B6 deficiency. In these women, administration of additional vitamin B6 as a dietary supplement corrects the chemical abnormality. Some researchers have recommended that the requirement may be as high as 10 mg per day. It is interesting to note that some women with depression and /or nausea seem to note improvement of these conditions when vitamin B6 supplements begun. Again, you should discuss with your clinician.

The best source of this vitamin are some vegetables and whole meat products. During milling of white flour, more than 75 percent of the vitamin B6 is destroyed. Since this vitamin is not added to flour products as part of an enrichment program, processed or refined products contain significantly less vitamin B6 than their whole grain counterpart.

B₁₂

This vitamin has been isolated as the “ant-pernicious anemia” factor. That is, it is essential for the production and development of red blood cells; without vitamin B12, anemia will eventually develop. All of the vitamin B12 available to man originally come from bacteria or fungi. Intestinal bacteria in man is a significant contributor in this respect. Vitamin B12 deficiency is seen chiefly among vegetarians and where special absorptive problems exist.

The requirement for vitamin B12 during pregnancy has been set at 2.6 microgram. In some cases, a dietary supplement or periodic intramuscular injection of vitamin B12 is indicated. Insufficient vitamin B12, an inherent problem in strict vegetarian diet, during pregnancy and breastfeeding, has been reported to result in some cases, in failure to thrive and developmental delay in infants and young children.