Eating Well: Water-Soluble Vitamins
Functions: In all the cells of the body, thiamin is needed for the breakdown and utilization of carbohydrates
Deficiencies In the United States, a deficiency of thiamin is rare because refined grains are enriched with this nutrient. Before refined grain products were enriched, a thiamin deficiency could result in a disease called beriberi. Signs of beriberi include loss of appetite, constipation, muscle weakness, pain or tingling in the arms and legs, swelling of the feet, mental depression, memory problems, shortness of breath, and fast heartbeat. Thiamin deficiency does occur in alcoholics because of impaired absorption.
Excesses: In some people an excessive intake can cause an allergic reaction. For most people, the body excretes the excess consumed. Extra thiamin does not boost your energy level. The Tolerable Upper Intake Level has not been determined due to a lack of data concerning adverse effects.
Adult males need 1.2 milligrams of thiamin each day and adult females need 1.1 milligrams daily.
The best food sources of thiamin include pork, peas, liver, and wheat germ. Good sources include whole-grain and enriched grain products, such as bread, rice, pasta, tortillas, and fortified cereals. Fair sources include pineapple, citrus fruits, milk, spinach, tomatoes, bananas, beans, nuts, seeds, and peanuts.
Riboflavin AKA Vitamin B-2
Functions: Riboflavin is involved in several vital metabolic processes in the body. It is necessary for normal cell and tissue function. Riboflavin is needed for normal protein and energy metabolism.
Deficiencies: A deficiency of riboflavin rarely occurs except in the severely malnourished. Symptoms can include eye disorders, dry and flaky skin, sores at the corners of the mouth, a sore, red swollen tongue, throat swelling, and anemia.
Excesses: There are currently no reports that indicate problems associated with an excessive intake of riboflavin.
Healthy, adult males need 1.3 milligrams of riboflavin daily and females need 1.1 milligrams daily.
The best food sources of riboflavin include liver, milk, cottage cheese and other dairy products. Good sources include eggs and meats. Fair sources are whole grains, enriched grains, green leafy vegetables, asparagus, broccoli, beans, and peas. Ultraviolet light, including sunlight, can quickly destroy riboflavin. That’s why milk is stored in opaque plastic or cardboard containers, not clear glass.
Functions: Niacin helps the body to metabolize and release the energy in carbohydrates and fats. It is involved with the making of protein and fat. Niacin helps promote healthy cells, gastrointestinal tract, skin, and nervous system.
Deficiencies: Pellagra is a disease that develops due to a deficiency of niacin. Symptoms include skin problems, diarrhea, dementia, and depression.
Excesses: An excessive intake of niacin can cause tingling and flushing of the skin, itching, digestive upsets, low blood pressure, abdominal pain, liver problems, and ulcers. Large doses of niacin have been used along with medication to help lower cholesterol levels. Speak with your physician before ever starting such a treatment plan. The Tolerable Upper Intake Level is 35 milligrams daily for both adult males and females.
Niacin recommendations are given in niacin equivalents (NE). This is because niacin comes from two sources: (1) niacin found in food and (2) the amino acid tryptophan which can be converted to niacin in the body. 1 milligram of niacin equals 60 milligrams of tryptophan. The recommended intake of niacin (as NE) is 16 milligrams daily for adult males and 14 milligrams for adult females.
The best sources of niacin include meats, poultry, and fish. Good sources include mushrooms, peanuts, legumes, and nuts. Fair sources include enriched grain products. Niacin is also produced in the body from the amino acid tryptophan.
Pyridoxine AKA Vitamin B-6
Functions:Pyridoxine is necessary for the normal breakdown of protein, carbohydrates, and fat. It helps turn the amino acid tryptophan into niacin and serotonin. Serotonin is a messenger in the brain. Niacin also helps produce body chemicals such as insulin, antibodies, and hemoglobin.
Deficiencies: A lack of pyridoxine may lead to anemia or weak blood, depression, nerve damage, seizures, greasy, flaky skin problems, and sores in the mouth.
Excesses: At extremely high doses, nervous system damage can occur. The Tolerable Upper Intake Level is 100 milligrams for both adult males and females.
The recommended intake for adult males is 1.3 milligrams during the ages of 19-50. From age 51 and above, the amount is 1.7 milligrams. The recommended intake for adult females is 1.3 milligrams during the ages of 19-50. From age 51 and above, the amount is 1.5 milligrams each day.
The best food sources of pyridoxine are blackstrap molasses, wheat bran and germ, soybeans, and brown rice. Good sources include organ meats, veal, lamb, chicken, fish, and pork. Fair sources include bananas, lima beans, cabbage, corn, oats, carrots, potatoes, and legumes.
Folic Acid (folacin or folate)
Functions: Folic acid is necessary for strong, healthy blood by helping to form hemoglobin. It plays a role in making new cells. By synthesizing the essential nucleic acids, DNA and RNA, normal cell division and replication occurs.
Deficiencies: A lack of folic acid produces poorly formed blood cells that cannot carry as much oxygen. A deficiency can affect normal cell division and impair growth. Pregnant women who do not get enough folic acid prior to conception and during the first trimester have a greater risk of having a baby with neural tube defects such as spina bifida.
Excesses: Consuming too much folic acid can mask a vitamin B-12 deficiency. An excess can also interfere with some medications. Sleep disturbances are possible as well as irritability. The Tolerable Upper Limit Level is 1,000 micrograms daily for both adult males and females.
The recommended intake of folic acid for adult males and females is 400 micrograms daily.
The best food sources of folic acid include liver, and green leafy vegetables. Good sources include lima beans, asparagus, broccoli, nuts, whole grains, fortified bread, rice, macaroni, noodles, cereals, oranges and orange juice, and lentils.
Cobalamin AKA Vitamin B-12
Functions: Vitamin B-12 works closely with folic acid to make red blood cells. Vitamin B-12 is necessary for a healthy nervous system. It helps the body to use fat acids and some amino acids.
Deficiencies: A lack of vitamin B-12 may lead to anemia, fatigue, nerve damage, stomach problems, a smooth tongue, or very sensitive skin. A vitamin B-12 deficiency can be masked by taking extra folic acid. Some people have a medical problem called pernicious anemia in which vitamin B-12 is not absorbed from the intestines properly. They are missing a body chemical called intrinsic factor that comes from the stomach lining. Others have a diseased intestine or have had a large part of their stomachs or intestines removed. These conditions require treatment with vitamin B-12 injections. Strict vegetarians, who eat no animal products, are at risk for developing a vitamin B-12 deficiency. The elderly are also at risk for vitamin B-12 deficiency since 10-30% absorb food-bound vitamin B-12 poorly. If not managed, this could cause severe anemia and irreversible nerve damage. It is important to include a variety of vitamin B-12 fortified foods or a dietary supplement to prevent these problems.
Excesses: There are no known symptoms of taking excessive amounts of vitamin B-12. Extra vitamin B-12 does not boost energy levels. A Tolerable Upper Intake Level has not yet been determined due to a lack of data of adverse effects.
Adult males and females need 2.4 micrograms of vitamin B-12 daily.
The best sources of vitamin B-12 include animal products, such as organ meats, beef, pork, fish, poultry, eggs, milk, and other dairy foods. Some foods are fortified with vitamin B-12 and are fair sources.
Functions: Biotin helps produce energy in your cells. It helps metabolize protein, fat and carbohydrates. Biotin is required by the body in order for four specific enzymes to function properly in metabolism.
Deficiencies A biotin deficiency is extremely rare in people who eat a healthy diet. In rare cases, these symptoms may appear: heart abnormalities, appetite loss, fatigue, depression, dry skin, low blood sugar between meals, acidic blood, and high blood ammonia. A chemical in raw egg whites prevents the body from absorbing biotin. This problem is prevented by cooking eggs, which destroys avidins ability to bind the biotin.
Excesses: There are currently no reported effects of consuming excess amounts of biotin. Therefore the Tolerable Upper Intake Level has not been determined.
The recommended intake for both adult males and females is 30 micrograms daily.
Biotin is found in a variety of foods. Good sources include eggs, liver, yeast breads, cereals, chocolate, peanuts, cauliflower, nuts, peas, and mushrooms. Fair food sources include milk. Biotin is also produced by the bacteria naturally found in the intestines.
Functions: Pantothenic acid helps with the breakdown and utilization of carbohydrates, proteins, and fats. It also helps the body produce energy in the cells. Pantothenic acid is involved in antibody production, adrenal activity, growth and metabolism.
Deficiencies: A deficiency of pantothenic acid is rarely a problem for those who eat a healthy diet.
Excesses: The only symptoms of excessive intake are occasional diarrhea and water retention. An excess may trigger a thiamine deficiency. No Tolerable Upper Intake Level has been determined for pantothenic acid due to a lack of data on adverse effects.
The amount needed by both adult males and females is 5 milligrams daily.
Pantothenic acid is found widespread in plant and animal foods. Meat, poultry, fish, whole-grain products, legumes, and eggs are considered the best sources. Good sources include broccoli, cauliflower, mushrooms, bran, sweet potatoes, potatoes, lima beans, soybeans, peanuts, peas, oatmeal, and cheese.
Functions: Vitamin C forms collagen, a connective tissue, which gives strength and structure by holding together muscles, bones, and other tissues. It helps to build, repair, and maintain red blood cells, bones, and other tissues. It gives strength and flexibility to blood vessels and capillary walls. This helps to prevent bruising. It helps the body to absorb iron found in plant foods. Vitamin C is necessary for cuts and wounds to heal. It keeps the gums healthy and protects you from infection by keeping the immune system strong and healthy.
Deficiencies: A lack of vitamin C can lead to a disease called scurvy. Scurvy causes muscle weakness, swollen and bleeding gums, loss of teeth, bleeding under the skin, bruising, poor wound healing, tiredness, and depression.
Excesses: Vitamin C is water-soluble, so the body excretes any excess consumed. However, very large doses may cause kidney stones and diarrhea. The Tolerable Upper Intake Level is 2,000 milligrams for both adult males and females.
Adult males need 90 milligrams of vitamin C daily and adult females need 75 milligrams daily. People who smoke need about twice as much vitamin C daily.
The best sources of vitamin C include citrus fruits (oranges, grapefruits, tangerines), strawberries, peppers, kiwi, and cantaloupe. Good sources include some green-leafy vegetables, cauliflower, tomatoes, potatoes, and pineapple.
