As people get older, it is normal for their bone density to decrease and their risk of fractures to increase somewhat. But in osteoporosis bones become less dense earlier and faster. Measures to prevent osteoporosis from developing can be particularly important for women and people with specific risk factors.
The risk of bone fractures due to osteoporosis depends on your bone density and other factors. These include your age, genes and being underweight. Lack of exercise, smoking and the use of some medications can play a role too.
Not all risk factors can be influenced. But there are some things that you can do to help strengthen your bones:
- make sure that you get enough calcium and vitamin D,
- stay physically active, and
- don't smoke.
How much calcium do we need?
The mineral calcium is important for making bone tissue and for keeping your teeth and nails strong. As we grow older, we need more calcium. Eating a diet that is rich in calcium can help to meet this need. Medical societies recommend between 700 mg and 1,200 mg per day. Our calcium calculator can help you to estimate how much calcium you are getting per day.
Are calcium supplements a good idea?
People who don’t have a much higher risk of bone fractures and who get enough calcium in their diet will most likely not benefit from taking calcium supplements. When the results of over 30 studies involving more than 50,000 people were analyzed and summarized, it was found that calcium supplements didn't affect the risk of bone fractures.
But calcium supplements can help people who do not manage to get enough calcium in their diet. The umbrella organization of German osteology-related societies (Dachverband Osteologie) and the German Institute for Risk Assessment (Bundesinstitut für Risikobewertung, BfR) recommend that these people take calcium supplements – but no more than 500 mg per day.
Can calcium supplements have side effects?
The side effects of calcium supplements include, in particular, constipation and kidney stones. Two large studies found that calcium tablets led to constipation in 70 out of 1,000 women, and to kidney stones in about 4 out of 1,000 women. It might be possible to lower the risk of kidney stones by drinking more water.
In both of the studies, the women took 1,000 mg of calcium per day. These side effects might be less common at a lower dose of 500 mg.
What role does vitamin D play?
As well as covering your calcium needs, it is also important to get enough vitamin D. Vitamin D helps bones to absorb calcium. Most of the vitamin D in our bodies is also produced by our bodies. We need enough sunlight (UV rays) to do so. But vitamin D can also be found in food or dietary supplements. According to current research, though, vitamin D supplements don't help.
In order for enough vitamin D to be made in the skin, the German Institute for Risk Assessment (BfR) recommends spending 5 to 15 minutes per day in the sun during the summer months, and 10 to 25 minutes per day in the sun in spring and fall. It is enough to have your face and hands exposed to the sunlight, and – if it’s warm enough – parts of your arms and legs too. In winter, the vitamin D that the body needs is largely supplied by stores built up in the body.
Amounts of vitamin D are measured in international units (IU), which is a fixed amount for the dose of a given substance. The umbrella organization of German osteology-related societies (Dachverband Osteologie) recommends that adults get 800 IU of vitamin D per day. According to the German Institute for Risk Assessment (BfR), people over the age of 65 shouldn't take more than 400 of those 800 IU in the form of supplements. Some dietary supplements, even those with a combination of ingredients, may contain a higher dose than this in a single tablet, for instance. So it's important to check the ingredient information on the package in order to stay below this maximum dose.
Are calcium and vitamin D supplements a good idea for people in need of nursing care?
Two studies looked at whether people who are in need of nursing care, and who aren't very mobile, benefit from taking calcium and vitamin D supplements. They might have an especially high risk of bone fractures because they spend so little time out in the sun and can often no longer get enough exercise.
The studies suggest that a combination of calcium and vitamin D supplements only prevents bone fractures in a small proportion of these people. The study participants took 1,200 mg calcium and 800 IU vitamin D per day in addition to their usual diet. Over a time period of two years, this prevented hip fractures in 10 out of 1,000 people who were in need of nursing care or had decreased mobility.
How important is exercise for healthy bones?
In general, a lack of exercise is one risk factor for developing osteoporosis: People who (have to) spend most of the day sitting or lying are more likely to develop osteoporosis than physically active people are.
Especially physical activities that involve carrying your own body weight help to promote bone growth. These include climbing stairs, jogging, brisk walking and strength training, but not swimming and cycling. One of the simplest forms of exercise with a relatively low risk of injury is brisk walking. Most people can still do this in older age too.
Many studies have found the following: After menopause, women can strengthen their bones by getting regular exercise in addition to their usual activities – ideally, at least three times per week for 45 minutes. Exercise also improves your fitness and coordination.
Physical activity is always associated with the risk of injury. Whatever type of exercise you do – whether it's low-intensity exercises or other sports – it's important to make sure it fits your own level of fitness, and to take care not to trip or fall. This is particularly true for people with osteoporosis who have already had a fractured bone or who have brittle bones. They should avoid types of sports and exercises that involve fast movements, heavy weights, or bending or twisting their spine too much. It's important that they talk to a physiotherapist or doctor about what type of exercise is most suitable.
Does it help to quit smoking?
Middle-aged and older people who smoke are at a greater risk of osteoporosis and bone fractures than people who do not smoke. There are a number of different theories as to why smoking is bad for your bone health. For example, it is thought that nicotine or the cadmium in cigarette smoke could affect bone metabolism, or that smoking might interfere with the absorption of calcium in the bones.
Apart from the harmful effects of smoking on bone health, there are many other reasons to quit smoking.
Bundesinstitut für Risikobewertung (BfR). Verwendung von Mineralstoffen in Lebensmitteln. Berlin: BfR; 2004.
Bundesinstitut für Risikobewertung (BfR). Verwendung von Vitaminen in Lebensmitteln. Berlin: BfR; 2004.
Dachverband der Deutschsprachigen Wissenschaftlichen Osteologischen Gesellschaften (DGO). Prophylaxe, Diagnostik und Therapie der Osteoporose bei postmenopausalen Frauen und bei Männern. AWMF-Registernr.: 183-001. 2017.
Zhao JG, Zeng XT, Wang J, Liu L. Association Between Calcium or Vitamin D Supplementation and Fracture Incidence in Community-Dwelling Older Adults: A Systematic Review and Meta-analysis. JAMA 2017; 318(24): 2466-2482.
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