Water-Soluble Vitamins

Unlike fat-soluble vitamins, water-soluble vitamins can easily dissolve in the watery fluids of your body. Because excessive amounts are generally excreted in the urine, there is less chance for toxic side effects but more chance for deficiencies. Therefore, it is important to regularly replenish these vitamins by eating healthy foods that supply ample amounts. Be extra careful during food preparation. Because some of these vitamins are easily washed away or destroyed by light, air, and heat, use small amounts of water, avoid overcooking, and only cut your fruits and vegetables right before eating them. The following provides a quick rundown on each of the nine water-soluble vitamins: eight B-vitamins and vitamin C.

Thiamin (B-1)

Thiamin is needed for the conversion of carbohydrate-rich foods into energy. B-1 also plays a role in keeping your brain, nerve, and heart cells healthy. A deficiency will lead to loss of energy, nausea, depression, muscle cramps, nerve damage, and muscular weakness. Although uncommon in the United States, a severe depletion of thiamin can result in the disease beriberi, causing potential muscle wasting and paralysis.

Foods rich in thiamin (B-1) include pork, beef, liver, peas, seeds, legumes, whole-grain products, oatmeal, and lamb.

Riboflavin (B-2)

Like its buddy thiamin, riboflavin plays a key role in the metabolism of energy. Furthermore, this vitamin is involved in the formation of red blood cells and is necessary for healthy skin and normal vision.

A riboflavin deficiency will cause dry, scaly skin, accompanied by cracks on your lips and in the corners of your mouth. If that's not enough, getting insufficient amounts can also make your eyes extremely sensitive to light.

Foods rich in riboflavin (B-2) include milk, yogurt, cheese, whole-grain breads and cereals, green leafy vegetables, meat, eggs, and beef liver.

Note: This vitamin is easily destroyed with exposure to sunlight; therefore, store these foods in the fridge, cabinet, or pantry.

Niacin (B-3)

This B-vitamin is also involved in energy-producing reactions in the cells that convert food to energy. In addition, niacin helps maintain healthy skin, nerves, and your digestive system. In some instances, you can use large doses of niacin as a cholesterol-lowering medication. However, you should only do this under the supervision of your doctor. Megadoses can cause hot flashes, itching, ulcers, high blood sugar, and liver damage.

In the rare case of a niacin deficiency, symptoms include diarrhea, mouth sores, changes in the skin, nervous disorders, and pellagra disease known to cause the “four Ds”: diarrhea, dermatitis, dementia (mental confusion), and death.

Foods rich in niacin (B-3) include meat, poultry, liver, eggs, nuts, enriched breads and cereals, brown rice, baked potatoes, fish, peanut butter, milk, and whole grains.

Pyridoxine (B-6)

Vitamin B-6 is a vital component for chemical reactions involving proteins and amino acids. (Remember those protein-building blocks?) It also participates in the formation of red blood cells, antibodies, and insulin, in addition to maintaining normal brain function. Deficiency causes skin changes, convulsions in infants, dementia, nervous disorders, and anemia.

Foods rich in pyridoxine (B-6) include lean meats, fish, legumes, green leafy vegetables, raisins, corn, whole grain cereals, pork, bananas, lentils, mangos, and poultry.

Cobalamin (B-12)

Vitamin B-12 assists in the formation of red blood cells and the normal functioning of your nervous system and is required for the synthesis of DNA (your genetic resumé). Because B-12 is only found in foods of animal origin, strict vegetarians might need to take a supplement to avoid a deficiency. Furthermore, this unique vitamin needs the help of another substance called intrinsic factor to be absorbed. Because intrinsic factor is made by the lining of the stomach, people with gastrointestinal disorders (especially found in the elderly) might need to get B-12 shots directly into the bloodstream. Symptoms of B-12 deficiency include nervous disorders and pernicious anemia.

Because a good amount of vitamin B-12 can be stored in the liver, it might take years for a deficiency to be recognized. As a result, people should have their B-12 levels checked starting at age 60 and every decade thereafter.

Foods rich in cobalamin (B-12) include meat, fish, poultry, eggs, milk products, and clams.

Folic Acid (Folacin, Folate)

Folic acid appropriately gets its name from the word foliage because it's primarily found in leafy, dark green vegetables. In addition to playing a vital role in cell division and red blood cell formation, this vitamin is needed to make the genetic material DNA.

In recent years, folic acid has gained a lot of attention for its ability to reduce neural-tube birth defects in newborn babies. Needless to say, it is imperative that pregnant mothers and women of childbearing years get the appropriate amounts of folic acid by both foods and supplementation. For this reason, folic acid is a key ingredient in most prenatal vitamins. Because this nutrient is involved in cell division, a deficiency will leave you vulnerable to anemia and an abnormal digestive function because your blood cells and cells of the intestinal tract divide most rapidly. Foods rich in folic acid include spinach, liver, beans (all types), peas, asparagus, lima beans, oranges, brussels sprouts, collard greens, and avocadoes.

Pantothenic Acid and Biotin

Pantothenic acid and biotin are both part of the “B-vitamin gang” that participates in the metabolism of energy. In addition, pantothenic acid also plays a role in the formation of certain hormones and neurotransmitters. Although both vitamins are vital for normal functioning, as of today there isn't a set RDA for either one. This is because deficiencies are so rare, and they are both found in a wide variety of plant and animal foods.

Vitamin C (Ascorbic Acid)

Now the million-dollar question, “Can vitamin C ward off the common cold?” The scientists say no. To date, there is no documented evidence supporting this notion. Interestingly enough, this vitamin might lessen the severity of those lousy symptoms experienced during a cold because vitamin C has a mild antihistaminic effect.

What else can vitamin C do? Let's just say if all the vitamins and minerals were on a pay scale according to the jobs they perform, vitamin C would be rolling. Vitamin C wears many hats, from helping to keep your bones, teeth, and blood vessels healthy to healing wounds, boosting your resistance to infection, and participating in the formation of collagen (a protein that helps support body structures). Another benefit from eating foods rich in vitamin C is that you increase the absorption of the mineral iron— good news for people with greater iron requirements

Although vitamin C deficiency is uncommon, it can cause a lowered resistance to infection, sore gums, hemorrhages, and in severe cases, the disease scurvy.

Foods rich in vitamin C include melons, berries, tomatoes, potatoes, broccoli, fortified juices, guava, kiwi, mangos, papaya, yellow peppers, and citrus fruits (oranges, grapefruits, etc.)

Excerpted from The Complete Idiot's Guide to Total Nutrition © 2005 by Joy Bauer. All rights reserved including the right of reproduction in whole or in part in any form. Used by arrangement with Alpha Books, a member of Penguin Group (USA) Inc.

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