According to the Dietary Supplement Health and Education Act, a dietary supplement as a product that performs the following:

• Enhances the foods you consume.
• Comprises of one or more dietary ingredient; including vitamins, minerals, amino acids, herbs, and other substances.
• Is available in pill, tablet, capsule, or liquid form.
• Is identified as a dietary supplement.

Various types of dietary, nutritional, and supplements exist. Vitamin and mineral supplements are forms of nutritional supplements comprising micronutrients designed to help a body operate effortlessly and enhance mental health.

Daily nutritional requirements should be fulfilled by eating a variety of foods as summarized in the United States Department of Agriculture’s Dietary Guidelines. In some instances, fortified foods or vitamin and mineral supplements may be useful in providing nutrients that may otherwise be consumed in less than the recommended daily amounts. In some instances, supplements and fortified foods may actually cause you to exceed safe levels of consumption of nutrients. The Dietary Guidelines for Americans offers these recommendations for specific classifications of people:

• Persons over the age of 50 should take vitamin B12 in the form of fortified foods or as a supplement. Older adults often have a decreased ability to absorb vitamin B12 from foods, crystalline vitamin B12 (this form of vitamin B12 is used in supplements and in fortified foods) is more easily absorbed.
• Older adults, especially those with dark skin and those who obtain do not get enough sunlight, should take extra vitamin D from vitamin D-fortified foods and/or supplements.

• Women of childbearing years who may become pregnant and adolescent females should consume foods rich in iron, such as meats, and/or iron-rich plant foods such as spinach or dry beans, or foods that have iron added like fortified cereals, along with a source of vitamin C, which aids the body in absorbing iron.
• Younger women of childbearing age who are pregnant or who may become pregnant should consume sufficient synthetic folic acid and folate daily from fortified foods or supplements.

You should keep in mind that vitamin and mineral supplements should not be a replacement for a healthful diet. Along with vitamins and minerals, foods also have many naturally occurring substances that help protect your health. Some questions you should ask yourself, as well as discuss with your physician, as recommended by the Food and Drug Administration (FDA) when considering whether you should take a vitamin or mineral supplement are:

• Do you have a restricted diet? Do you limit meat, or milk or dairy products, from your diet, or eat less than five servings of fruits and vegetables daily?

• Do you consume less than two meals a day?
• Do you usually eat your meals alone?
• Do you have three or more drinks daily?
• Do you take three or more prescription or over the counter medications daily?
• And, without intending to, have you gained or lost over ten pounds of weight in the past six months?

You should discuss with your doctor whether or not a vitamin or mineral supplement is right for you. If you are currently taking dietary supplements, you need to inform your doctor. Research indicates many individuals do not tell their physicians they are taking a dietary supplement or are considering using one. You may think side effects occur only with prescription medications, but some dietary supplements can create side effects if taken in conjunction with other drugs or if certain health conditions exist. You doctor can advise you about taking a dietary supplement if you are currently on medication.

The National Institute of Health Office of Dietary Supplements has a series of supplement fact sheets that offer scientifically-based overviews of numerous vitamins and minerals. These can provide a good source for a discussion with your doctor regarding whether or not vitamin or mineral supplements are something you should add to your diet. The FDA also provides an array of articles and consumer advisories to aid consumers regarding dietary supplements, as well as warnings and safety information, labeling, evaluation information, and the FDA's function in regulating these supplements.

Generally, the best way to stay healthy is to choose a wide variety of nutritious foods from all five food groups. Nutrient insufficiencies are not typical among Americans, but for different reasons some people are unable to obtain the recommended nutrient amounts without the addition of supplements or fortified foods. Even with a healthy and balanced diet, some individuals may require nutrient supplements depending on their unique situation. Due to allergies, some individuals are limited in their food choices, or if they have a medical condition or are following a vegetarian or vegan diet. For instance, animal foods are a primary source of vitamin B12, so those following a vegan diet should eat fortified foods and/or take a supplement. Women of childbearing years need to obtain adequate folic acid from fortified foods. They can get folic acid from cereals, grains, supplements and/or maintain a varied diet that includes foods with folic acid. Folic acid helps reduce the risk of some birth defects. If lab tests indicate that a woman's iron status is low during pregnancy, her doctor should recommend an iron supplement. Vitamin D may be a concern for infants, children, and young adults. Babies who are breastfed and children, who consume less than the RDA of vitamin D-fortified milk or formula, as well as those with increased risk of deficiency, will need supplemental vitamin D.

The method you use in taking a supplement can be as important as the product itself since both may affect how much of a nutrient your body actually absorbs. Some general rules of thumb are:

• Taking a large dose of a particular mineral will compete with other minerals and reduce their absorption. Calcium is a mineral usually taken in large doses. If you take a calcium supplement, take it at an alternative time of day than any other mineral supplements or multivitamin/multi-mineral supplement combinations you take.
• Magnesium is sometimes taken in large doses and should preferably be taken separately from other minerals. Also, if you take high doses of zinc for an extended period of time, be aware that it can create a copper deficiency, so you may need to supplement that mineral as well.

Some vitamins can improve the absorption of other nutrients. For instance, vitamin C enhances the absorption of iron from supplements and plant foods. A, D, E and K, fat-soluble vitamins, are better absorbed if taken with a meal that contains fats. Studies indicate that modest to large doses of fat-soluble vitamins decrease absorption of other fat-soluble vitamins due to their competing with each other. Absorption of vitamin K seems to be reduced by other fat-soluble vitamins while vitamin A absorption is minimally affected and may even be better absorbed when taken with vitamin E. Vitamins D, E, or K appears to have maximum absorption when taken several hours before or after other fat-soluble vitamins. Taking certain supplements with food can minimize digestive side effects. For instance, taking magnesium with food can decrease the incidence of diarrhea, and taking iron with food can diminish the possibility of an upset stomach. Water-soluble vitamins B and C can sometimes cause nausea or acid sensitivity when taken on an empty stomach, so take them along with a meal. However, vitamin B12 is an exception since it is best absorbed on an empty stomach. A vitamin B12 supplement may be required if you are vegan or eat very little animal products since this vitamin is found only in animal-based foods.

Guidelines established by the Institute of Medicine can help you to understand how much of a vitamin or mineral you should take. The Recommended Dietary Allowance (RDA) and the Adequate Intake (AI) are the quantities of a vitamin or mineral you need in order to maintain good health and remain well-nourished. These numbers are adapted depending on age group or gender. The highest daily amount of vitamins and minerals you can take safely without the risk of or serious side effects or overdose is known as the Tolerable Upper Intake Level (UL). For some nutrients, the greater you exceed the UL, the better chance you will encounter problems. Distinct from the RDA and the UL, the FDA utilizes a different measure for the nutrients your body needs. The only measurement you will see on food and supplement labels is the Daily Value (DV) one. Since space is limited, there is a requirement for one individual reference number. The DV is defined as the amount of a vitamin or nutrient that you need to maintain top health from consuming a diet of 2,000 calories a day. The DV is at times identical to the RDA. Even though the details may be dissimilar, keep in mind that the RDA and DV are both established to assist you in obtaining the nutrients required to prevent disease and avoid any issue created by the lack of nutrition.

Since high doses of some supplements possess risks, you need to be aware when it is permissible to consume more than the RDA or DV. One method is to look for the UL of a nutrient. Some vitamins and minerals allow you to safely take a dose greater than the RDA or DV without getting close to the UL. For example, the average person can take more than 50 times the RDA of vitamin B6 before reaching the UL. Consequently, you need to always be cautious. Keep these helpful tips in mind:

• Some supplements pose more of a risk than others do. With certain vitamins and minerals, the UL is very close to the RDA. Therefore, you can easily consume too much. For instance, a man who takes just over three times the RDA of vitamin A would obtain more than the UL.
• Supplements are meant as additions to your diet. Experts maintain that you should consume a well-balanced diet and take supplements to satisfy any nutritional gaps. Or, you can take a daily multivitamin with minerals for nutritional assurance. Even your pet would benefit from taking vitamins.

• The UL is usually the limit for all sources of a nutrient, so it can include the amount you receive from both food sources and supplements. When figuring whether you have reached the UL for an individual nutrient, take into consideration the foods you consume.
• Many nutrients can be dangerous if taken in high doses. To be safe, keep clear of the UL for any nutrient. If you happen to have a health condition, check with your doctor before taking any supplements so that you are aware of any side effects or if they can interfere with any medications that you take.

The safest means of buying vitamins and supplements is to obtain them from a reputable vitamin or health food retailer or your health practitioner.