It is recommended for everyone to balance the variety of food so you get a nutrient rich diet. However for some people it can be difficult to obtain appropriate calcium through their diet alone. These groups may include:
Older adults: With increasing age comes decreased absorption of calcium. Therefore middle aged or older people may need to consider calcium supplementation to keep their bones and muscles healthy.
Menopausal women: It is extremely important for women going through pre-menopause and post-menopause years to sustain calcium and avoid bone loss during the process. If some calcium is obtained through the diet, supplementation of upto 1000 mg is usually adequate.
Strict vegetarians: People who are strictly on a plant based diet and do not consume dairy at all, must consider calcium supplementation to avoid weakening of bones in later stages of the deficiency.