Calcium and zinc oral solution should not be fed together with milk powder. It is better to take calcium alone and avoid taking it at the same time with milk, milk powder, food from vegetables, as well as zinc and iron supplements. The protein in milk and calcium will combine to form milk lumps and the calcium cannot be absorbed by the body. Excessive intake of oxalic acid in food affects the absorption of calcium. The body’s absorption of calcium is competitive with zinc and iron, and taking them at the same time will not only inhibit the absorption of zinc and iron, but also interfere with the absorption of calcium itself. If you need to supplement with other elements, it is best to stagger the time and take them more than 2 hours apart. There are other considerations for calcium supplementation, such as splitting the same dose of calcium, one dose is better absorbed than a large dose. Calcium is better absorbed at night before bedtime, when gastrointestinal peristalsis is slower and food stays longer in the gastrointestinal tract, which is conducive to calcium absorption. Blood calcium levels are higher during the day and lower at night, especially in the middle of the night and early morning. In addition, calcium supplementation should be supplemented with vitamin D. Calcium absorption requires vitamin D, and the balance of calcium metabolism is also affected by vitamin D. You can choose to take cod liver oil or vitamin D3 preparations, and you can also get sunlight to promote the conversion of cholesterol into vitamin D in the skin.