Vitamins have some very specific roles in our bodies and play a big role in energy production. Our bodies cannot make them but also cannot function without them. They come from the food we eat. Since they exist in many different foods, eating a variety is the only way of getting them all. Thus, to avoid deficiencies, a well-balanced diet is needed with diversity and moderation. 

It is difficult to transfer (shuttle) vitamins from food into our bodies. Before the food we eat can be used for energy it needs to be digested, i.e. broken down into its simplest form of individual nutrients. Following digestion, the body must take up, or absorb, the individual nutrients to either use them for energy or store them for later.

Contrary to common belief, there is no value in consuming extra vitamins in the form of supplements, above what is necessary, i.e. not more than 100% of the recommended daily amount. It has been shown that supplements can actually be harmful when taken in amounts greater than what is considered beneficial.

Dietary supplements are products taken by mouth which contain a dietary ingredient intended to supplement the diet. In the UK many supplements are considered to be foods, not a type of medicine or pharmaceutical, and so they are regulated under general food laws by the Food Standards Agency (FSA) and the Department of Health. These laws are not as stringent as those for medicines.

The RDA is the amount of vitamins and minerals that healthy people need for a good daily diet

Changes associated with normal ageing increase nutritional risk for older adults. As activity levels and energy requirements decrease with age, there is a reduction in the total energy intake, as well as a decline in the intake of nutrients, including vitamins and minerals.

Vitamin A is a little complicated. There are two main forms of vitamin A: provitamin A—carotenoids, beta-carotene and others—and preformed vitamin A, or retinoids. Provitamin A, carotenoids, are found in plants.

The B vitamins are amongst the most important vitamins. Like the A vitamins, there are eight different B vitamins, each with its own chemistry and function in the body.

Thiamine is known as a carbohydrate burner as its active form is involved in several enzyme functions associated with the metabolism of carbohydrates, amino acids and fatty acids.

Vitamin B2 or Riboflavin is a water-soluble vitamin that helps convert food into energy. It is known as the fat burner vitamin, as you cannot properly process your fats without it.

Vitamin B3 is a very important water-soluble vitamin, also known as nicotinic acid. Niacin is used by the body to make a biologically active form, nicotinamide coenzyme (NAD), which is involved in all stages of energy creation.

Vitamin B5, or pantothenic acid, is water-soluble and is essential to all forms of life. In the diet, the principle active form of pantothenic acid is Co-enzyme A (CoA). Upon ingestion, dietary CoA turns into pantothenic acid in readiness for intestinal absorption. Following absorption into cells, pantothenic acid gets converted back into CoA, which is vital to a multitude of biochemical reactions that sustain life.