Who should not take vitamin supplements?

Children, pregnant and nursing women, people with health conditions.

Explanation:

Dietary supplement are very popular today but they are not a replacement for a balanced diet. Many supplements contain active ingredients that may be harmful to the body, especially if bought without consulting a health care provider first.

Children that eat a healthy, balanced diet don't need vitamin supplements as the food they eat contains all the nutrients they need to grow and develop properly. Pregnant and nursing women must ask their doctor before taking any kind of supplements as they can interfere with the embryo's development and even cause some birth defects, nursing women may find that some vitamins effect the quality of breast milk.

People with health conditions, awaiting a surgery or recovering from one should always take vitamins under supervision, the same applies to people taking any kind of medicine on a regular basis.  

the treatment of other conditions (e.g., cystic breast disease) and for other medical reasons. Mastectomy is most effective when the cancerous tumour is discovered at an early stage and the malignant cells are localized. In order to best ensure the removal of all cancerous tissue, however, a margin of tissue surrounding a tumour and, sometimes, other nearby structures are also removed. Thus, there are several types of mastectomy, the selection of procedure depending on the location and extent of the disease (determined by X ray, thermography, and other diagnostic techniques) and the nature of the cancerous cells (determined by biopsy).

Explanation:

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