Taking a multivitamin and a dietary supplement together is not recommended, as it can reduce absorption and cause adverse interactions that can be harmful to health, especially in children. It's not efficient to take them together, as the body's ability to absorb vitamins will be reduced if taken together. However, some vitamins work better together because the body absorbs them more easily that way. For example, iron and vitamin C are one of these combinations.
Vitamin C helps the body absorb plant-based iron. In addition to interacting with other supplements, some recipes interact with supplements. Manufacturers must produce dietary supplements that meet minimum quality standards, contain no contaminants or impurities, and are accurately labeled. If you are taking zinc, it is recommended that you also take a 2 mg copper supplement to maintain the balance of these two minerals in the body.
Green tea has health benefits, but it's not a good idea to take an iron supplement (or eat iron-rich foods) at the same time as green tea. Some consumers may believe that a so-called “natural” product, such as an herbal supplement or fish oil, cannot harm them. Iron insufficiency, or anemia, prevents this process, causing fatigue and requiring iron supplementation. You can have side effects when you combine certain supplements with antidepressants and anti-anxiety drugs.
To make sure you're getting the right ratio, check with your provider for guidance on combining calcium and magnesium mineral supplements.