Vitamin C & Biotin

Vitamin C and biotin are both water-soluble vitamins, which means they dissolve in water when they enter your body and enter your bloodstream immediately. Because they travel through your bloodstream, your body uses what it needs and then the kidneys remove excess amounts of the vitamins from the blood and rid the body of them through your urine. To ensure that your body has access to adequate amounts of vitamin C and biotin, you have to eat foods that contain these vitamins every day.

Vitamin C Functions

Your body needs vitamin C for the growth and repair of all of your tissues. Vitamin C is also a vital component in the synthesis of collagen, a protein and connective tissue that helps make skin, tendons, ligaments and blood vessels. Vitamin C also plays a role in wound healing and immune function and acts as an antioxidant. Because of these roles, vitamin C is often associated with cold prevention. In "Nutrition and You," Joan Salge Blake says that there are no research studies that show vitamin C can prevent the common cold, but it may reduce duration and severity once you contract a cold.

Vitamin C Needs and Sources

Adult women need 75 mg of vitamin C, and adult men need 90 mg of vitamin C per day. If you are a smoker, you need to consume an additional 35 mg of vitamin C daily because smoking increases the rate at which your body breaks down the vitamin. Americans meet 90 percent of their vitamin C needs through fruit and vegetable intake. Sources of vitamin C include oranges, orange juices, cantaloupe, tomatoes, peppers, potatoes and broccoli.

Biotin Functions

Like the other B vitamins, biotin acts as a coenzyme, which means it helps enzymes produce chemical reactions. The major function of biotin is to metabolize carbohydrates, protein and fat. The metabolism of these nutrients allows your body to obtain energy from them. Your body also uses biotin to synthesize fat.

Biotin Needs and Sources

Both male and female adults need 30 mcg of biotin daily. The B vitamin is available in a variety of foods, including whole-grain breads, whole-grain cereals, nuts, peanut butter, legumes, meat, milk and eggs. Salge Blake says that most adults easily meet their biotin needs, and because of this, biotin deficiency is extremely rare.