You probably already know that we need calcium in order to have strong teeth and bones. Did you also know that you need calcium in your blood to transmit neurological signals and to allow your muscles to contract? Your heart is a muscle and if it can’t contract, or beat, properly, you’re in big trouble! As the National Institutes of Health explains, if you don’t take in enough calcium, your body begins to draw calcium out of your bones to keep the calcium level in your blood good so that your heart can keep beating.
How Much Do We Need?
The American Society for Metabolic and Bariatric Surgery (ASMBS) recommends all weight loss surgery folks take calcium citrate daily. They recommend 1500 mg daily for lap band and vertical sleeve gastrectomy patients, 1500 to 2000 mg daily for gastric bypass (RNY) folks, and 1800 to 2400 mg for duodenal switch patients. We need to take calcium citrate supplements because we may not consume enough calcium in our diet, since we can only eat small amounts of food. In addition, RNY and DS folks don’t absorb all of the calcium they consume due to malabsorption, which is why the ASMBS advises them to take more calcium than lap banders and sleevers.
Why Calcium Citrate?
Notice that the ASMBS specifically says weight loss surgery folks should take calcium citrate. There are several different kinds of calcium and they are not all the same. Calcium supplements typically contain calcium citrate, calcium carbonate, or tricalcium phosphate. Some contain a combination of different kinds of calcium.
There is a reason the ASMBS recommends calcium citrate over calcium carbonate and tricalcium phosphate. It takes a lot of stomach acid to break down calcium carbonate and tricalcium phosphate for absorption and some people produce more stomach acid than others. Gastric bypass surgery is known to reduce the production of stomach acid, but bariatric surgeons often prescribe medication to reduce the production of stomach acid in patients that have other forms of weight loss surgery. Other things, including simply getting older, can also reduce the production of stomach acid. Calcium citrate is simply absorbed better.
In addition to not being absorbed as well as calcium citrate, calcium carbonate sometimes contributes to the development of kidney stones. However, a study conducted at the University of Western Ontario found that taking calcium citrate actually reduces the risk of kidney stones.
Taking Your Calcium Citrate
The ASMBS recommends taking your calcium citrate in doses of 500 to 600 mg at a time, because we can’t absorb more than that at once. Wait at least two hours between doses. If you take a multivitamin with iron or an iron supplement (and the ASMBS says you should be taking those), take them at least two hours away from your calcium citrate, because calcium blocks the absorption of iron.
Vitamin D is a fat soluble vitamin that helps us absorb calcium. You don’t have to take vitamin D with your calcium citrate, although many calcium supplements contain vitamin D. However, you need to have a good level of vitamin D in your blood in order to absorb calcium properly. A simple blood test can determine if you’re getting enough vitamin D.
American Society for Metabolic and Bariatric Surgery. (http://nutrition.otago.ac.nz/__data/assets/file/0005/4784/BariatricNutritionReading.pdf. Nutritional Guidelines.
Office of Dietary Supplements. http://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/. Calcium.
Livestrong. http://www.livestrong.com/article/519104-calcium-citrate-kidney-stones/. Calcium Citrate and Kidney Stones.