Osteoporosis

The bone matrix is made up of about two thirds of inorganic minerals, 10 to 15 percent of water and 20 to 25 percent of collagen and other proteins. The most important mineral for the bone structure is calcium, which is present in the bone in the form of calciumhydroxylapatit. To be able to form bone substance, the osteoblasts also need vitamin K and vitamin C apart from calcium; furthermore, some vitamins (folic acid, B12, D) and magnesium are indirectly involved in the bone structure.

Too much coffee consumption (caffeine), smoking, alcohol and underweight have a negative effect on the bone structure. On the other hand, physical activity in particular, calcium and vitamin D contribute substantially to the formation of more bone mass.

Osteoporosis shows itself in a reduced bone mass and a destroyed microarchitecture of the bone tissue. The bones lose in elasticity and stability so that it is easier for them to break. If bone fractures have already occurred due to osteoporosis, doctors will term this a manifest osteoporosis. The most frequent fractures occur in the areas of the hips, vertebral bodies or forearms.

As an osteoporosis prophylaxis, the current Guideline Osteoporosis of the DVO Umbrella Organization Osteology e.V. recommends a supply of 1000 milligrams calcium daily. This is the quantity also recommended for adults as part of a balanced diet by professional nutrition societies such as the German Society for Nutrition (DGE).

In food, the most important calcium providers are milk and milk products. Apart from the high calcium content, another big advantage is the bioavailability in these food items. Contributors are also other milk ingredients such as lactose and vitamin D which promote the resorption. Apart from animal food products, some vegetables like kale, broccoli, fennel and leek also contain relatively much calcium. Despite the low bioavailability, they can contribute to achieving the recommended calcium supply. Other contributors are mineral water rich in calcium (at least 150 mg/l).

Vitamin D supports the absorption of calcium from the bowels as well as its integration in the bones. Overall it is responsible for the calcium and phosphate balance in bowels, bones and kidneys. By means of sunlight, the body produces the major part of its vitamin D requirement itself. It is recommended by the Federal Institute for Risk Assessment (BfR) to spend about five to fifteen minutes daily in the sun in summer so that sufficient vitamin D can be produced in the skin; in spring and autumn about ten to twenty-five minutes. It is enough if the face and hands and, depending on the temperature, also arms and legs, are uncovered.

In winter our body falls back on its vitamin D reserves created during the brighter season.

Only a small portion of the vitamin D comes from food. It is mainly contained in fish, meat and eggs in the form of vitamin D₃ (cholecalciferol). Humans can synthetize this substance in the skin themselves. Vegetable food, for example edible mushrooms, contains vitamin D in the form of Vitamin D₂ (ergocalciferol). Vitamin D₂ and D₃ have the same biological activity, both need to be transferred to the active form calcitriol.

The DGE (German Society for Nutrition) estimate a vitamin D requirement for children, adolescents and adults at 20 micrograms per day. Adults absorb daily about two to four micrograms of vitamin D via their food. The quantity of vitamin D is often denominated in international units (IE). 1 µg is equivalent to 40 IE, or 1 IE is equivalent to 0.025 µg. The umbrella organization osteology recommends that adults take 800 IE vitamin D daily which, according to the specialist society’s assessment, suffices for an osteoporosis prophylaxis.

There are two other important factors when dealing with the prevention of osteoporosis: normal weight and movement.

Underweight encourages the occurrence of osteoporosis. Thus, people with anorexia or emaciating illnesses such as COPD have an increased osteoporosis risk. Old people should keep an eye on their body weight and in the case of involuntary loss of weight take countermeasures. Especially in old age, gradual loss of weight may develop due to a decreasing feeling of hunger and thirst or problems when eating. This may also be connected to a lack in protein, minerals and vitamins. If the loss of weight continues further, the person concerned will need to seek medical advice.

The force of gravity, tensile and pressure loads enhance the bone structure. Especially activities where one’s own body weight comes into effect will strengthen the bones. Part of this are for example climbing stairs, jogging, walking and strength training. On the other hand, swimming and cycling only do very little for the bone structure. For senior citizens there are especially designed movement and training programs aimed at those areas which are mainly endangered by fractures. Also balance training helps older people to reduce the risk of falling.