If you drink more than two drinks a day with caffeine, you need to slow down, as it can decrease the amount of calcium in your body.If you have a thyroid dysfunction, calcium, iron, and magnesium supplements must be separated from your thyroid medication by at least 4 hours for optimal absorption.Some calcium supplements, particularly calcium carbonate, can cause bloating, gas, and constipation. However, calcium absorbs better when taken in two doses of 500 mg each. Please help us continue to provide you with our trusted how-to guides and videos for free by whitelisting wikiHow on your ad blocker. Calcium citrate is most easily absorbed by the body and you can take it on an empty stomach. Absorption, how much of a nutrient is actually utilized by the body, depends on many factors, including the form of a supplement (for example, calcium citrate versus calcium carbonate) and the “delivery system” (tablet, capsule, or liquid). Avoid taking calcium supplements with very high fiber meals. They are best taken together. I am 52 years old. "This article is very informative. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/3\/39\/Best-Absorb-Calcium-Supplements-Step-2-Version-2.jpg\/v4-460px-Best-Absorb-Calcium-Supplements-Step-2-Version-2.jpg","bigUrl":"\/images\/thumb\/3\/39\/Best-Absorb-Calcium-Supplements-Step-2-Version-2.jpg\/aid1228138-v4-728px-Best-Absorb-Calcium-Supplements-Step-2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"