Prepared by
Melissa Brener, MS

Vitamin C is mainly found in citrus fruits such as oranges, lemons and grapefruits. It is also present in potatoes, tomatoes and green vegetables. Fresh fruits and vegetables are the best sources of vitamin C because cooking and processing these foods destroy the vitamin. The RDA for vitamin C is 60 mg/day.

Table of Contents for Vital Vitamins Introduction What You Will Learn Food Guide Pyramid Review What Are Vitamins? The Fat-Soluble Vitamins The Water Soluble Vitamins Do You Need a Vitamin Supplement? Summary Web Sites to Visit Review questions Back to Nutrition Curriculum Lessons

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The Water-Soluble Vitamins

There are two water-soluble vitamins - the vitamin B complex and vitamin C. Because these are water-soluble, they can be dissolved in the cellular fluid. Therefore, excess amounts are easily removed from the body in the urine. When foods containing water-soluble vitamins are cooked, they tend to lose many of these vitamins due to high cooking temperatures and the process of cooking in water. Cooking vegetables in small amounts of water helps to limit the amounts of vitamins lost.

The B Vitamins

Thiamin

Thiamin is found in meat (especially pork), dairy foods, fortified grain products, green beans, peanuts, other beans and seeds. White bread is fortified with thiamin and is the major dietary source in the United States. A thiamin deficiency causes the disease beriberi. Before white bread was fortified with thiamin, this disease was a widespread problem in the U.S. because signs of deficiency begin after less than two weeks of a thiamin-free diet. Symptoms of beriberi include weakness, tingling, irritability, muscle pain and loss of appetite. Currently, the elderly and alcoholics are the two populations most at risk for a thiamin deficiency. Elderly people often eat more highly processed foods, which have lost most of their thiamin during processing. Alcoholics have a harder time absorbing thiamin into their bodies.

Riboflavin

Riboflavin aids the body's cells in producing the energy needed to live and grow. A lack of riboflavin in the diet causes the disease ariboflavinosis. The symptoms of this disease include an inflamed mouth and tongue, nervous symptom disorders and mental confusion.

Good sources of riboflavin are leafy green vegetables, mushrooms, liver and other meats, dairy products and enriched grain products.

Niacin

Niacin is part of several vital cellular pathways. It plays a part in the production of energy and helps make fatty acids (parts of fats) among other things. A lack of niacin in the diet causes the deficiency disease pellagra. Pellagra means rough, painful skin - the first symptom of the disease. Pellagra first causes dermatitis, which is worsened by the sun. If left untreated, it can cause diarrhea, dementia and finally death. Because white breads are enriched with niacin (along with thiamin and riboflavin), pellagra is no longer a problem in the United States. Too much niacin in the diet (over 100 milligrams per day) can cause increased blood flow to the skin, creating a flushed appearance. Other symptoms include headaches and itching.

Pantothenic Acid

Pantothenic acid is a very common vitamin. In fact, a deficiency is very rare because pantothenic acid is found in so many foods. Symptoms of a deficiency are dermatitis and neuromuscular disorders. Pantothenic acid is involved in many pathways that work in the body. Foods that are especially good sources of pantothenic acid include eggs, liver, yeast, peanuts and milk.

Biotin

Biotin can be found in several foods or can be made in the body. Egg yolks, liver, cheese, peanuts and yeast are all good sources of biotin. Most people are not at risk for a biotin deficiency. Rarely, however, infants can be born with low levels of the enzyme needed to make biotin in the body. This can lead to a deficiency. Symptoms of a biotin deficiency include dermatitis and hair loss.

Vitamin B6

This vitamin, also known as pyridoxine, is involved in many body processes. Some people have claimed that vitamin B6 is helpful in treating premenstrual syndrome (PMS) in women. This claim has not been proved though.

Vitamin B6 can be found in many fruits and vegetables, such as broccoli, cantaloupe, bananas and spinach. Meat, fish and poultry are also good sources. A vitamin B6 deficiency is found most often in alcoholics because alcohol affects the structure of vitamin B6. The RDA for vitamin B6 is 2.0 milligrams per day for men and 1.6 milligrams per day for women. Vitamin B6 levels can easily become toxic if too much is consumed. Toxicity symptoms include numbness of the extremities and permanent nerve damage.

Folate

Folate, also known as folacin or folic acid, is a very important vitamin, especially for women who are pregnant or of child-bearing age. If a pregnant woman does not consume enough folate in her diet or has a folate deficiency, her child could be born with a neural tube defect such as spina bifida or anencephaly (absence of a brain). If a person has a folate deficiency, they usually have a type of anemia known as megaloblastic anemia. This means that the red blood cells cannot mature and divide to make new cells. Therefore, they grow very large and fragile. Pregnant women, alcoholics and people taking certain medications have the biggest risk of folate deficiency.

There are several good food sources of folate. These include breakfast cereals that have been fortified with folate, leafy green vegetables, melons, oranges, strawberries, liver, eggs and beans. Fresh fruits and vegetables are better sources than processed, canned or cooked ones because these processes destroy part of the folate. The RDA for folate is 180-200 micrograms per day for adults. However, women of child-bearing age should eat 400 micrograms per day to prevent birth defects.

Vitamin B12

One of the functions of vitamin B12 is to help the body use folate. A deficiency of vitamin B12 can cause a type of anemia known as pernicious anemia. Because vitamin B12 and folate deficiencies both cause anemia, it is sometimes difficult to tell which one a person is deficient in. Food sources of vitamin B12 include meat, poultry, seafood, eggs and organ meats. Milk products also contain vitamin B12. Because the best sources of vitamin B12 are animal foods, people who are strict vegetarians should make sure they consume vitamin B12 from other sources. These can include soy products, fortified cereals and vitamin supplements. The RDA for vitamin B12 is 2 micrograms per day for adults.

Vitamin C

Vitamin C, also called ascorbic acid, is absorbed from the food in the small intestine. If a person eats between 30-120 milligrams per day of vitamin C (the RDA is 60 milligrams per day), the body uses 80-90% of this vitamin C. However, if a person consumes larger amounts, the body uses a much lower percentage and excretes the rest in the urine. Excess vitamin C can also cause diarrhea.

Vitamin C has several functions. One is to make collage, a protein used by the body in connective tissue. Vitamin C also helps the body absorb and use iron more efficiently. Therefore, if a person is anemic, they should consume more vitamin C in addition to more iron. Vitamin C is also an antioxidant, so it protects the body from free radicals.

If a person has a vitamin C deficiency, they may develop a disease called scurvy. Scurvy causes the connective tissue in the body to change. This results in weakness and small hemorrhages around the hair follicles that are visible on the surface of the skin. The gums and joints also bleed.

Vitamin C is mainly found in citrus fruits such as oranges, lemons and grapefruits. It is also present in potatoes, tomatoes and green vegetables. Fresh fruits and vegetables are the best sources of vitamin C because cooking and processing these foods destroy the vitamin. The RDA for vitamin C is 60 milligrams per day.

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