Vitamins and Minerals

Where once we could obtain all the vitamins and minerals we needed from our food, changes in food production systems and in our dietary choices have resulted in dietary deficiencies. Vitamins are chemical compounds and minerals are chemical elements. The role of vitamins is to control the chemical reactions within the body to convert food into energy and living tissue. They also support the body to use the energy nutrients, maintain normal body tissue, act as a regulator, and are only needed in small amounts. Our body requires 13 vitamins, 3 of which are produced by the body itself - biotin, pantothenic acid, and vitamin K which are produced in the intestine. Each vitamin and mineral has a specific function or meets specific body needs. The table below lists some of the important vitamins and minerals and describes their function and sources. Deficiency in these vitamins and minerals will result in the corollary of the function outlined. Many people who supplement their diet with vitamins and minerals do so with the belief that more is better - that if vitamins and minerals are good for us, if we have more we will have even more benefit. This is not the case. Too much of some vitamins and minerals can cause toxic reactions. These are also outlined in the table below.

Table: Selected vitamins and minerals.

Vitamin	Function	Overdose/Toxicity	Good Sources
Vitamin A	Prevents night blindness Promotes healthy eye function Keeps skin, hair, and nails healthy Helps ward off bacterial infection	Joint and bone pain, Hair loss Skin changes Headaches Blurred vision Fatigue	Green, yellow, or orange vegetables, Cantaloupe, Apricots, Sweet potatoes
Vitamin B₆	Carbohydrates and protein metabolism Helps form red blood cells Proper nerve function	Nerve destruction	Bananas Meats, poultry, fish Potatoes Broccoli Cereals and grains
Vitamin B₁₂	Proper nerve function Helps form red blood cells Builds genetic material	None known	Meats, poultry, fish Milk Eggs Vegans may need supplementation
Folic Acid	DNA and RNA synthesis Helps form red blood cells Important in growth and development Helps prevent birth defects	None known	Orange and grapefruit juice Green leafy vegetables Poultry Supplement recommended for pregnancy Dried beans
Vitamin C	Promotes healing of cuts and wounds Helps resist infection Keeps gums healthy Strengthens blood vessel walls	Diarrhea Kidney stones	Citrus fruits (oranges, grapefruit) Strawberries Cantaloupe Green or red peppers Broccoli
Vitamin E	Helps form red blood cells, muscles, and other tissues Antioxidant	Muscle weakness Headaches Fatigue	Seeds and nuts, Seafood, Eggs, Oils
Calcium	Helps build strong bones and teeth Involved in muscle contractions and nerve function	Muscle and abdominal pain Calcium kidney stones	Milk and milk products (yogurt, cheese), Tofu, Broccoli, Calcium fortified orange juice, Some fortified cereals
Chromium	Works with insulin for proper glucose metabolism	None known	Egg yolks, Meat, Whole grains, Cheese
Iron	Helps carry oxygen to body tissues including muscle	Liver disease Arrhythmias	Red meat, seafood, and fish Dried apricots Dried beans, Fortified cereals, Supplement recommended for pregnancy
Phosphorus	Works with calcium to build and maintain bones and teeth Helps convert food to energy	Lowers blood calcium	Dairy products, Egg yolks, Meat, poultry, fish, Legumes, Soft drinks
Potassium	Vital for muscle contractions and nerve transmission Important for heart and kidney function Helps regulate fluid balance and blood pressure	Slower heart beat Kidney failure	Milk and yogurt Many fruits and vegetables (especially oranges, bananas, and potatoes)
Zinc	Important in function of many enzymes Wound healing	Nausea and vomiting Abdominal pain	Seafood, Meats, Eggs, Whole grains