Collagen is a protein found in connective tissues of the body. It is significant in making certain parts of the body such as nails strong and is also an important factor in joint health. Collagen supplements come in various forms. One of the most common is called Gelatin.
Calcium supplements come in several different forms, including calcium carbonate and calcium citrate. Calcium citrate is the easiest for your body to absorb and digest, making it less likely to cause adverse side effects like gas. However, calcium citrate only contains 21 percent elemental calcium, while calcium carbonate contains 40 percent. Elemental calcium is the actual amount of calcium present in a supplement.
Multivitamins often contain more than just vitamins. They also provide you with minerals, and their mineral content can cause constipation. Iron in supplements commonly causes constipation, and calcium increases your risk of constipation as well, according to Brown University.