How does exercise strengthen the bones?

Putting strain on bones strengthens them: For instance, the bones in your legs bend very slightly with every step you take when walking. The cells inside the bones feel the pressure. They then make new bone tissue. Exercise is important too. It strengthens your muscles and improves your sense of balance and coordination. So exercise reduces your risk of falls as well.

The types of movement and exercises that are suitable will depend on your age, bone density, any medical conditions you have, your overall health, and whether you've already had any bone fractures.

Why is it important to get enough calcium in your diet?

The mineral calcium is essential for our bones: Calcium makes up more than half of our bone tissue.

We can normally get enough calcium in our diet. It is mainly found in milk and dairy products such as cheese and yogurt. Water and some vegetables, such as spinach, also contain calcium. But the amount of calcium found in tap water and mineral water varies a lot depending on the product and where it is from. The only way to find out is to ask the water company or read the information on the label.

Most people in Germany get enough calcium from milk and dairy products. People who are vegan or lactose-intolerant can still make sure they get enough calcium, though. Calcium-enriched milk substitutes such as oat milk, almond milk or soy milk are an alternative. The amount of calcium also varies from product to product here. Our calcium calculator can help you to estimate how much calcium you are getting per day.

People with a disease that may affect calcium absorption, such as a chronic inflammatory bowel disease, should talk to their doctor.

What does the sun have to do with vitamin D?

As well as covering your calcium needs, it is also important to get enough vitamin D. We need vitamin D to absorb calcium from our bowel and get it into our bones. Our bodies produce about 80% to 90% of the vitamin D they need themselves. But that can only happen if you spend enough time outside. This is because vitamin D is made in your skin with the help of sunlight (UV radiation).

For the skin to be able to produce enough vitamin D, the Federal Institute for Risk Assessment recommends spending at least 5 to 15 minutes outdoors during the day in summer and about 10 to 25 minutes in spring and fall. The sun doesn't have to be out; the UV light passes through clouds.

Your face, hands and (where possible) part of your arms or legs should be exposed. In winter, the vitamin D that the body needs is largely supplied by stores built up in body fat and muscle tissue over the summer.

Only small amounts of vitamin D can be found in foods – for example, in egg yolk, mushrooms and fatty fish.

Who benefits from dietary supplements with calcium and vitamin D?

In recent years, vitamin D has repeatedly been hailed as a miracle worker in the fight against many health problems. But there is usually no good evidence to support these claims. Dietary supplements only make sense for a few people. These mainly include people in nursing care who often only spend small amounts of time outdoors and do not always get enough calcium in their diet. There is proof that dietary supplements with vitamin D and calcium reduce the risk of bone fractures in people who live in retirement and care homes.

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Dietary supplements with calcium and/or vitamin D do not prevent bone fractures in people who aren't at particular risk. No other health benefits have been proven, either.

Why can too much alcohol be a problem?

Drinking too much alcohol increases the risk of falls, accidents and bone fractures. For those reasons alone, it is a good idea to only drink alcohol in moderation. Drinking too much alcohol can be harmful to your health for other reasons, too.

For healthy adults, the German Centre for Addiction Issues recommends

• that women drink no more than 12 grams of alcohol per day, i.e. a small glass of beer (300 ml) or a small glass of wine (125 ml).
• that men drink no more than 24 grams of alcohol per day, i.e. two small glasses of beer (600 ml) or a large glass of wine (250 ml).
• drinking no alcohol on at least two days per week.

It is not always easy to follow these recommendations. A few tricks and strategies can help, though.

Does quitting smoking help?

Smoking increases your risk of osteoporosis and bone fractures. There are a number of different explanations for this negative effect of smoking on bones. For example, experts believe that the cadmium in tobacco smoke stops bones from absorbing calcium.

There are also many other health-related reasons to stop smoking. A lot of people find it difficult to give up smoking. But various types of support are available.

How can you prevent falls?

Most osteoporosis-related bone fractures are the result of a fall. Hip fractures in particular can drastically change your life. Many people need nursing care as a result, especially those aged over 80.

Whatever your age, it's always a good idea to be as physically active as possible. People who withdraw from daily life and avoid exercise for fear of a fall aren't doing themselves any favors: their muscles and bones then get weaker faster and their coordination gets worse, making falls more likely.

There are also many other things you can do to avoid falls:

• Get rid of tripping hazards in your home: For example, loose cables, rugs and door thresholds, as well as poor lighting and objects that are in the way.
• Use aids: Non-slip mats and handrails can help to prevent falls. Well-fitting, comfortable shoes are also important.
• Check your medication: Certain medications can increase your risk of falls or weaken your bones. For example, some sleeping pills can make you tired during the day, too, increasing the risk of falls. You can talk with your doctor to find out if you really need all of the medications that you are taking, whether it might make sense to change the dose, and whether the different medications might interact with each other. It is generally a good idea to make a medication list or schedule.
• Have health problems checked out: Other diseases can also increase the risk of falls – for example, if you have cataracts and can't see well because of them. It is then important to have those problems treated, too.

Sources

• Avenell A, Mak JC, O'Connell D. Vitamin D and vitamin D analogues for preventing fractures in post-menopausal women and older men. Cochrane Database Syst Rev 2014; (4): CD000227. [PMC free article: PMC7032685] [PubMed: 24729336]
• Bundesinstitut für Risikobewertung (BfR). Bewertung von Vitaminen und Mineralstoffen in Lebensmitteln. 2022.
• Bundesinstitut für Risikobewertung (BfR). Verwendung von Mineralstoffen in Lebensmitteln - Toxikologische und ernährungsphysiologische Aspekte. 2004.
• Bundesinstitut für Risikobewertung (BfR). Verwendung von Vitaminen in Lebensmitteln - Toxikologische und ernährungsphysiologische Aspekte. 2004.
• Bundesinstitut für Risikobewertung (BfR), Deutsche Gesellschaft für Ernährung (DGE), Max Rubner-Institut (MRI). Ausgewählte Fragen und Antworten zu Vitamin D. 2014.
• Dachverband der Deutschsprachigen Wissenschaftlichen Osteologischen Gesellschaften (DGO). Prophylaxe, Diagnostik und Therapie der Osteoporose bei postmenopausalen Frauen und bei Männern. AWMF-Registernr.: 183-001. 2017.
• Dai Z, McKenzie JE, McDonald S et al. Assessment of the Methods Used to Develop Vitamin D and Calcium Recommendations - A Systematic Review of Bone Health Guidelines. Nutrients 2021; 13(7): 2423. [PMC free article: PMC8308557] [PubMed: 34371932]
• Dautzenberg L, Beglinger S, Tsokani S et al. Interventions for preventing falls and fall-related fractures in community-dwelling older adults: A systematic review and network meta-analysis. J Am Geriatr Soc 2021; 69(10): 2973-2984. [PMC free article: PMC8518387] [PubMed: 34318929]
• Robert-Koch-Institut (RKI). Antworten des Robert Koch-Instituts auf häufig gestellte Fragen zu Vitamin D. 2019.
• Zhao JG, Zeng XT, Wang J et al. 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. [PMC free article: PMC5820727] [PubMed: 29279934]

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  Because IQWiG is a German institute, some of the information provided here is specific to the German health care system. The suitability of any of the described options in an individual case can be determined by talking to a doctor. informedhealth.org can provide support for talks with doctors and other medical professionals, but cannot replace them. We do not offer individual consultations.

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