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Calcium and vitamin D are an absolute must for bone health. But not every form of these supplements is equally useful.

If you a woman who has passed menopause and you have been diagnosed with osteoporosis or told you are at risk of it, there is no doubt that you need calcium and vitamin D.

The Women's Health Initiative studied 36,282 postmenopausal women, some of whom were given 1000 mg of calcium and 400 IU of vitamin D for five years, while others were given a placebo. At the end of the observation period, researchers found that:

  • Women who took calcium and vitamin D were 38 percent less likely to experience a hip fracture (broken hip).
  • Women who took calcium and vitamin D were 18 percent less likely to experience a fracture anywhere in the body, although this result was not statistically significant.
  • Taking calcium and vitamin D did not increase the risk of heart attacks, and it tended to reduce the risk of metastatic cancer. These results likewise failed to reach statistical significance.
Because some of the 18,000 women who were assigned a placebo pill took calcium and vitamin D on their own, the researchers were able to compute a minimum effective dose of calcium for women to prevent fractures. Any supplementation of 500 mg or more calcium per day and any supplementation of 400 IU or more of vitamin D improves bone health.

Calcium and vitamin D don't make a magic bullet for bone protection. The Women's Health Initiative only found scientifically robust results for using these two supplements to prevent hip fractures. However, calcium and vitamin D are an important first step in a holistic program for bone health. They just aren't where you need to stop.

Here are 10 things every woman needs to know about using calcium and vitamin D for stronger bones.

1. Some kinds of calcium are more effective than others

Calcium oxide is inexpensive and shelf-stable, but your body can't absorb it without the action of stomach acid. You need to take it with food. Some studies have found that the calcium oxide form of the supplement is not as effective as other forms of calcium for preventing fractures, but it still has some value. If you have low stomach acid, you need to take calcium citrate, and take your calcium supplement with a meal. If you don't have problems with digestion, you can use calcium gluconate, lactate, or phosphate supplements, and you can take them on an empty stomach if you like. The calcium citrate malate form of the mineral added to fruit juices is effective for anyone who needs calcium.

2. Smaller doses of calcium are more effective than larger doses

Most people can only absorb about 500 mg of calcium at a time. This means that to get 1000 mg of calcium into your system every day, you need to take at least two doses of the supplement. 

3. It's possible to get your calcium from food, but some planning may be necessary

Just about anyone can get the calcium they need from food, but just about no one does. That's because calcium absorption from food is, well, complicated:

  • Dairy foods are a great source of calcium, but not everyone can or chooses to consume them. If you do eat dairy, yogurt is usually the best source of calcium. Ice cream and cream cheese provide relatively little calcium. About three servings of dairy a day provides all the calcium your body needs.
  • Some plant foods are great sources of calcium. Heading the list is tofu, because of the way it is processed (in a calcium solution). Turnip greens, kale,  and raw broccoli also contain high levels of calcium.
  • Other plant foods interfere with your body's absorption of calcium. Whole grains, beans, seeds, and nuts contain phytic acid, which binds calcium and keeps the intestine from absorbing it. Collard greens, sweet potatoes, and spinach contain oxalates that bind calcium and can aggravate any tendency toward kidney stones. It's OK to eat these foods, just not at the same time you consume high-calcium foods.
  • High-protein foods increase calcium excretion, so osteoporosis patients used to be told to avoid eating too much protein. It turns out, however, that high-protein foods also increase calcium absorption, and they increase absorption more than they increase excretion. Your bones need protein to make the collagen that glues minerals in place, so make sure you get enough. "High" protein is not strictly necessary. But if you eat a ot of meat, be sure to eat fruits and vegetables to provide the alkali your kidneys need to maintain a healthy pH without taking calcium out of your bones.
  • Caffeine does cause the body to excrete calcium, but a cup of caffeinated coffee only causes the loss of 2 to 3 mg out of the 1000 mg a day your body needs. Eating chocolate-coated coffee beans, however, could be a problem.

4. The easiest way to get your vitamin D is to take a 1000 IU capsule every day

Vitamin D is available in pills, sprays, and powders, and as fermented fish oil. The least expensive (and least smelly) way to get your D is to take a capsule. Unless you like rotten cod liver, you are more likely to stick to your program if you just take a capsule of vitamin D once a day. There's no need to take more than 10,000 IU per day even if you are deficient. Extremely high doses of the vitamin can actually harm bones.

  • Bolland MJ, Grey A, Avenell A, Gamble GD, Reid IR. Calcium supplements with or without vitamin D and risk of cardiovascular events: reanalysis of the Women's Health Initiative limited access dataset and meta-analysis. BMJ. 2011 Apr 19.342:d2040. doi: 10.1136/bmj.d2040. Review. PMID: 21505219.
  • Barrett-Connor E, Chang JC, Edelstein SL. Coffee-associated osteoporosis offset by daily milk consumption. JAMA 1994.271:280-3.
  • Kerstetter JE, O’Brien KO, Caseria DM, Wall DE, Insogna KL. The impact of dietary protein on calcium absorption and kinetic measures of bone turnover in women. J Clin Endocrinol Metab. 2005 Jan. 90(1):26-31.
  • Prentice RL, Pettinger MB, Jackson RD, Wactawski-Wende J, Lacroix AZ, Anderson GL, Chlebowski RT, Manson JE, Van Horn L, Vitolins MZ, Datta M, LeBlanc ES, Cauley JA, Rossouw JE. Health risks and benefits from calcium and vitamin D supplementation: Women's Health Initiative clinical trial and cohort study. Osteoporos Int. 2013 Feb. 24(2):567-80. doi: 10.1007/s00198-012-2224-2. Epub 2012 Dec 4. PMID: 23208074.
  • Weaver CM, Alexander DD, Boushey CJ, Dawson-Hughes B, Lappe JM, LeBoff MS, Liu S, Looker AC, Wallace TC, Wang DD. Calcium plus vitamin D supplementation and risk of fractures: an updated meta-analysis from the National Osteoporosis Foundation. Osteoporos Int. 2016 Jan
  • 27(1):367-76. doi: 10.1007/s00198-015-3386-5. Epub 2015 Oct 28. Erratum in: Osteoporos Int. 2016 Aug
  • 27(8):2643-6. PMID: 26510847.
  • Photo courtesy of SteadyHealth

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