[Medical Q&A] Is it better to take calcium tablets before going to bed?

Planner: Chinese Medical Association

Reviewer: Zhao Yu, Chief Physician, Peking Union Medical College Hospital

Many people think that taking calcium tablets before going to bed is more effective, but in fact, this practice may not be scientific. Generally speaking, taking calcium tablets before going to bed is not the best choice.

When sleeping at night, the human body is in a static state and lacks exercise. In this case, the calcium supplemented is prone to premature deposition or synthesis, which may not only cause gastrointestinal discomfort, but also cause calcium to deposit on the blood vessel walls, increasing the risk of vascular sclerosis. Therefore, compared with nighttime, it is more appropriate to supplement calcium during the day, because the amount of activity during the day is greater, and calcium is more easily used and absorbed.

As for whether to take calcium tablets before or after meals, it depends on the type of calcium preparation. Pure calcium gluconate is easier to decompose and absorb faster. If taken on an empty stomach, it may combine with gastric acid to form precipitation after entering the stomach, thus affecting the absorption effect. However, many calcium preparations on the market are complex calcium, which is usually combined with organic compounds. After taking it, the calcium will be slowly released and absorbed. Therefore, whether it is taken on an empty stomach or after a meal, the effect on absorption is relatively small.

In addition, the following points should be noted during calcium supplementation:

(1) The importance of magnesium and phosphorus: There is a saying among the people that "if you take calcium supplements without taking magnesium, you will regret it", which shows that magnesium deficiency will affect calcium absorption. Similarly, calcium and phosphorus are also a "good pair". If you only take calcium supplements and ignore the role of phosphorus, it may also reduce the efficiency of calcium absorption.

(2) The role of vitamin D: Vitamin D can promote the transfer and absorption of calcium ions, helping calcium to be better deposited in bones. For people with more severe osteoporosis, in addition to obtaining vitamin D through sun exposure, they can also take appropriate vitamin D preparations to improve the effect of calcium supplementation.

To sum up, it is more appropriate to supplement calcium during the day, and pay attention to the balanced intake of auxiliary elements such as magnesium, phosphorus and vitamin D, so as to achieve better calcium supplementation effects.