Will taking calcium tablets at night cause kidney stones?

Speaking of stones, I believe everyone is familiar with it. There are many types of stones, among which kidney stones are the more common type of stones in life. Patients who have suffered from stones should know that stones are extremely harmful to the human body. There are many factors that lead to the formation of stones, and the accumulation of calcium in the body is one of them. Many people will ask if taking calcium tablets at night will cause stones. Let me answer this question for you below.

1. Calcium absorption and excretion

Calcium absorption and excretion are mainly absorbed in the small intestine, filtered by the kidneys, and reabsorbed from the renal tubules. 80% of the calcium that cannot be absorbed is excreted in the feces, and 20% is excreted in the urine. From this we can see that only a small portion of the unabsorbed calcium is excreted in the urine. There are many causes of urinary stones. Among them, those related to calcium absorption are absorptive hypercalciuria and reabsorptive hypercalciuria. For example, hyperparathyroidism can lead to increased intestinal calcium absorption, which can cause hypercalciuria. In addition, taking large doses of calcium supplements will increase urinary calcium excretion and may cause urinary stones.

2. The right amount of calcium will not cause stones

For normal people, supplementing an appropriate amount of calcium before going to bed generally does not lead to the occurrence of stones. To avoid the risk of urinary stones, it is not recommended for people with hyperparathyroidism or who need to take large doses of calcium supplements to take them before bed. Don't take too much at one time. It is best to take the daily amount in several doses, with each dose not exceeding 500 mg of elemental calcium to maximize absorption. It is good to supplement calcium in moderation; excessive supplementation may cause hypercalcemia.

3. Cannot be taken with oxalic acid

When taking calcium supplements with food, be careful not to take them together with oxalic acid. Some green vegetables contain more oxalic acid, which easily react with calcium to form calcium oxalate precipitates and increase the risk of stones. However, blanching these vegetables can remove most of the oxalic acid, which can improve the utilization rate of calcium.

Generally speaking, taking appropriate calcium tablets at night will not cause the occurrence of stones, but we should try not to take calcium supplements at night.