- People over 65 years old might need to take a vitamin B supplement, because their food is often more deficient, because their body absorbs less this vitamin and because they take many medications that can interfere with the vitamins.

- Vegetarians: A well-planned vegetarian diet can meet most of the vitamin needs. However, strict vegetarians can suffer from a lack of cobalamin (vitamin B12) which is found only in foods of animal origin, except for brewer's yeast. The contribution of a multivitamin complement may be necessary.

- Persons with hypertension: The administration of vitamins and minerals, along with a change in their habits can improve this disease.

- People who smoke: smoke destroys some vitamin C, therefore smokers should consider increasing the intake of foods containing the vitamin or taking some supplements.

- People with diabetes: Vitamins can help improve the health of the people who need to take insulin.

- Children: To achieve a harmonious growth, we must ensure that children have a reasonably balanced diet that provides them with the necessary vitamins. Sometimes, with the consent of the physician, the administration of a supplement may be helpful.

- Pregnant women: The feeding of pregnant women is crucial for infant development. It would be advisable to consult your doctor about the possible needs of a vitamin supplement. It has been seen how a daily intake of 400 mcg of folic acid helps prevent spinal cord defects in newborns.

- Women who take birth control pills: In this group, a possible deficiency of vitamin C, vitamin B6 and B2 may exist. A vitamin supplement could be interesting.

- People who drink too much alcohol: Intake of vitamin B and C can help their liver to prevent liver disease.

- People who have little exposure to sunlight: Sunlight is necessary for the production of vitamin D. Those who do not expose to the sun should consider taking a vitamin supplement.