Calcium and Vitamin D for Bone Health: Should You Take Supplements?
Guest: Dr. Diane Kamen – Rheumatology & Immunology
Host: Dr. Marcy Bolster – Rheumatology & Immunology
Welcome to an MUSC Podcast
Dr. Marcy Bolster: I’m Dr. Marcy Bolster. I’m a professor of Medicine in the Division of Rheumatology at the Medical University of South Carolina. I’m Medical Director for the Center for Osteoporosis and Bone Health at MUSC. Today, I’ll be speaking with Dr. Diane Kamen who is an assistant professor of Medicine in the Division of Rheumatology at MUSC. We’ll be discussing calcium and vitamin D supplementation in bone health and osteoporosis. Welcome, Dr. Kamen. Thank you for being here today.
Dr. Diane Kamen: Thank you. It’s my pleasure.
Dr. Marcy Bolster: A lot of people take a multivitamin everyday. Does that contain calcium and vitamin D?
Dr. Diane Kamen: You’d have to look at the bottle. Even the vitamins that are made for women probably do not have your daily recommended intakes. That brings up the point, again, about spreading it out through the day, for the calcium. I think you do get the maximum benefit taking it at least twice a day. Typically, multivitamins, you wouldn’t want to take twice a day; it wouldn’t be necessary.
Dr. Marcy Bolster: So, a multivitamin once a day would be helpful, and that would have some calcium and vitamin D, and a calcium supplement that has both calcium and vitamin D, as you said, twice a day?
Dr. Diane Kamen: Yeah, that would be a good combination.
Dr. Marcy Bolster: Do you think there’s a benefit to taking a supplement, in the form of a tablet, as opposed to trying to get the appropriate amount of calcium and vitamin D through diet?
Dr. Diane Kamen: For calcium, it might be possible to get enough from the diet. Although, even people who say they have a lot of dairy in their diet aren’t getting as much as they think they might be getting, so I do think there’s a role for the calcium supplement, and there are a lot of people who are lactose intolerant. In those cases, it’s very important to get it [calcium] in the form of a supplement so you’re not having any side effects from having it in the diet. But, for vitamin D, there are only certain foods, like oily fish…
Dr. Marcy Bolster: Like what?
Dr. Diane Kamen: We used to get our vitamin D from cod liver oil. And most people don’t want to have to go back to doing that, so the supplements are a nice way of getting the purified vitamin D without the fishy taste of the cod liver oil or having to eat excessive amounts of sardines to get enough vitamin D. We do recommend the supplements. And you said tablet, there are also gel caps which are easier to swallow, for the vitamin D, and then there are chewable tablets for the calcium.
Dr. Marcy Bolster: How much calcium is in an 8-ounce glass of milk? Is it possible for a patient to drink a glass of milk a day and get enough calcium? What would be required?
Dr. Diane Kamen: An 8-ounce glass of milk will typically have about 300 milligrams of calcium. So, if you need 1200, or 1500, milligrams a day, you would have to drink quite a bit of milk. And, of course, we encourage a more varied diet, getting calories from fruits and vegetables, fiber. You wouldn’t want to get all of your calcium just from milk and dairy products.
Dr. Marcy Bolster: So, what are some of the foods that are high in calcium?
Dr. Diane Kamen: The foods that we classically think about are dairy products such as milk, cheese, and yogurt. But what some people don’t realize is that there are vegetables with significant calcium levels, such as broccoli.
Dr. Marcy Bolster: The goal is 1200 to 1500 milligrams of calcium a day, but that would include dietary sources, or the foods that people eat, in addition to what they might take as a supplement. So, the total should be 1200 to 1500?
Dr. Diane Kamen: Yes. That’s correct.
Dr. Marcy Bolster: And now certain drinks, like orange juice, are fortified with calcium.
Dr. Diane Kamen: Yes, that’s a good point. There’s orange and, probably, other juices as well. It’s good to look at those labels. You can actually learn a lot from looking at the label. But what you’re probably not going to see, at least at this point in time, is significant amounts of vitamin D added to foods. Even if it says vitamin D fortified, usually it’s in the amounts of 100 to 400 IU. You really need to be getting at least 1000 IU a day.
And we don’t tell people to get all of that from sunbathing. We know that skin cancer is a risk. At the same time, there are a lot of reasons why people wouldn’t get enough vitamin D just from sunlight. People have to work during the day, living inside, or away from areas that have a lot of UVB light exposure.
Dr. Marcy Bolster: So, a multivitamin also contains vitamin D, is the amount of vitamin D in a multivitamin going to be adequate for what’s recommended?
Dr. Diane Kamen: No. At this point in time, the multivitamins on the market do not have adequate amounts of vitamin D. Vitamin D, you can take it once a day, or even once a week, if you’re getting enough of it to be the equivalent of 1000 to 2000 IU a day. The problem is that the multivitamins, right now, contain 400 IU, on average, some of them, only 200; some of them, up to 800.
Dr. Marcy Bolster: So, would it be okay for a patient to take an additional supplement of vitamin D, say, 1000 to 2000 IU?
Dr. Diane Kamen: Absolutely, yeah. We also have gel caps that are easier to swallow, other ways to get the vitamin D supplementation. We typically recommend the over-the-counter supplements on a daily basis.
Dr. Marcy Bolster: Is it important to measure the level of calcium, or vitamin D, in the blood so that a patient knows that they’re taking the right amounts?
Dr. Diane Kamen: It’s a good idea to have your calcium level checked at your annual physical, but it doesn’t tend to reflect your intake of calcium through your diet. Vitamin D, on the other hand, you can actually check a 25-hydroxyvitamin D level. That’s also a blood test. And that will reflect how much vitamin D is really available to you for all the important things that vitamin D does. In addition to bone health, it’s important for cardiovascular and immune system health as well.
There’s been a lot of research recently on what is a normal level of vitamin D in the blood. I think experts would all agree that at least 30 nanograms per milliliter is the goal. However, there’s the thinking, too, that we might find out that different populations of people need even more. But, right now, we do check the levels to see what the baseline is to make sure that we’re at least at 30 nanograms per milliliter.
Dr. Marcy Bolster: Do you have any comment on whether or not any person should decide on their own to take calcium and vitamin D?
Dr. Diane Kamen: I think it’s probably a good idea to have a discussion with your primary care doctor, who would be aware of the benefits and potential risks of calcium and vitamin D. There are people that are at higher risk of having kidney stones from high calcium levels in the blood and urine. We recommend that people run through the potential risks and benefits with their physician before starting on a self treatment plan. With this being available over the counter, it does make it easier, of course, for people to get supplements.
Dr. Marcy Bolster: So, you do recommend that a patient discuss with their physician the appropriate doses of calcium and vitamin D supplementation?
Dr. Diane Kamen: Absolutely.
Dr. Marcy Bolster: Dr. Kamen, thank you very much for being here today. This has been very informative.
Dr. Diane Kamen: Thank you, Dr. Bolster, my pleasure.
Thank you for listening to the information about the Center for Osteoporosis and Bone Health at the Medical University of South Carolina. In order to get an appointment, patients may self-refer or they may be referred by their physician. The scheduling number is (843) 876-2663 (876-BONE.) I hope this information is helpful to you.