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Dietary supplements

Dietary supplements are used to support good health and as alternative forms of medicine. They include, but are not limited to, vitamins, minerals, botanicals and amino acids. These substances come in different preparations; they can be tablets, capsules, liquids or powder. Many people choose to take vitamins, minerals and amino acids as supplements because they do not get enough through their diets. Because there are negative side effects linked with some dietary supplements, consult a health care provider before using them.

Unlike prescription drugs, dietary supplements do not go through strict and rigorous testing standards. However, the Ministry of Health's Office of Dietary Supplements is monitoring their manufacturing and distributing.

There are several types of dietary supplements.


Vitamins are nutrients that your body needs for proper health. You need 13 different types of vitamins (A, C, D, E, K, B6, B12, folate, thiamine, riboflavin, niacin, pantothenic acid ,biotin) for your body to control processes such as digestion, cell division and nerve function Water-soluble vitamins, such as the different B vitamins and vitamin C, are absorbed into your system and the extra concentrations eliminated through your kidneys. Fat-soluble vitamins, such as vitamins D, E, A and K, are stored in your body to be used when you need them. When the body has insufficient amounts of any of these vitamins, also known as deficiencies, it can result in health complications. Taking high doses of vitamins can be toxic. 


Minerals are types of nutrients that are essential to your health. You can get them through your diet and by taking dietary supplements. Your body uses minerals to build bones, form cells, move various muscles, produce the hormones and enzymes that control your metabolism and as electrolytes to balance body fluids. Macro minerals, such as calcium, magnesium, chloride, phosphate, potassium and sodium, are minerals that your body needs large amounts of. Trace minerals, such as chromium, fluoride, iron, iodine and selenium, are nutrients that your body only needs small concentrations of. Just like having a mineral deficiency, taking too much of a mineral can cause health problems. 


Botanicals, also called herbs and phytomedicines, are parts of plants that are used to promote good health or as alternative forms of medicine. Various botanicals have a history of use in traditional medicine and are linked to specific cultural practices. As dietary supplements, botanicals can be sold in the form of powders, capsules, teas, liquid extracts and tablets. Many botanicals have side effects and should be used under the guidance of your health care provider.

Amino Acids

Your body uses amino acids to make the proteins that it needs to grow and repair cells. Amino acids that your body cannot produce by itself are called essential because they need to come from your diet. You can get amino acids from plant and animal based foods, as well as through dietary supplements. Many amino acids supplements are commonly marketed to athletes to improve athletic performance. 

To start using any supplements you take these steps:

Step 1

Look at your diet. If your diet contains a variety of fruits and vegetables, legumes, whole-grains, lean meat, fish and low-fat dairy products, you probably do not need a dietary supplement. A supplement is more helpful for if you have poor eating habits, are a vegetarian eating a limited variety of foods, are a postmenopausal woman or a woman who is breastfeeding or have had surgery on your digestive tract and are unable to absorb nutrients from the foods you eat.

Step 2

Talk to your doctor before taking a supplement. If you take medication on a regular basis, the supplement might interfere. Supplements can increase the risk of bleeding during surgery, or affect your response to the anesthesia, according to the National Center for Complementary and Alternative Medicine.

Step 3

Check the safety of the supplement before taking it. Dietary supplements differ from prescription medications; the manufacturers do not have to prove its efficacy or safety before placing it on the market.

Step 4

Check the label for expiration dates. Dietary supplements lose their potency over time, especially when in hot and humid climates. If the expiration date is nearing, or the item has no expiration date, do not purchase it.

Step 5

Read the list of ingredients. "Natural" doesn't always mean safe. Some ingredients can cause liver damage, while others can damage your heart. Speak to your doctor about the ingredients in the supplement of your choice to ensure your safety.

Step 6

Take your supplement as directed. Taking more than the recommended dose can result in unpleasant -- sometimes dangerous -- side effects. If this occurs, even when taking the recommended dose, stop taking the supplement immediately and make an appointment with your doctor.

Step 7

Find a safe place to store your supplements. Dietary supplements are not intended for use by children and teens unless their doctor prescribes them; store your supplements where your children cannot find them. Make sure the area is dry and cool; this ensures the life and efficacy of your supplement.


• Stanford Medicine: Dietary and Herbal Supplements

• U.S. Food and Drug Administration: Fortify Your Knowledge About Vitamins

• The Merck Manual of Medical Information: Minerals and Electrolytes

• Office of Dietary Supplements: Botanical Dietary Supplements

• "Journal of the International Society of Sports Nutrition"; Dietary Supplements and Sports Performance: Amino Acids; Melvin Williams; December 2005

• National Center for Complementary and Alternative Medicine: Using Dietary Supplements Wisely

• Dietary Supplements: Nutrition in a Pill?

Science Article