The researchers talked about the diet for maintaining bone health
The condition of bones in old age largely depends on the reserve of bone mass formed in childhood and youth. However, nutrition, physical activity, and lifestyle continue to influence the rate of weight loss even after age 30. At the same time, milk alone or calcium intake is not enough: protein, vitamin D and regular exercise are also necessary for skeletal health. What foods are really good for bones, what is known about soy, chia seeds and prunes, and why supplements do not always prevent fractures — in the Izvestia material.
Why you need to think about bone health in advance
Bone is a living tissue that is constantly being renewed. Some cells destroy old areas, while others form new ones. In childhood and adolescence, bone formation prevails, so the skeleton becomes larger and stronger.
Peak bone mass is usually reached between the ages of 20 and 30. After that, the volume of bone tissue gradually decreases, as the processes of its destruction begin to outpace recovery. This does not mean that it is too late to strengthen bones after the age of 30. Nutrition and physical activity cannot completely reverse age-related changes, but they can slow down premature bone loss and support muscles that balance and risk falls depend on.
Women can lose bone mass especially quickly after menopause. A decrease in estrogen levels accelerates the destruction of bone tissue. However, it is wrong to consider osteoporosis as an exclusively female disease. Men tend to have higher bone mass initially and decrease more slowly, but they also experience osteoporosis and fractures as they age.
According to the International Osteoporosis Foundation, the disease affects about 500 million people over the age of 50. Every year, about 37 million low—energy fractures occur among people over the age of 55 - injuries that occur after falling from a height of their own height or other relatively minor injury.
The most severe consequence is considered to be a fracture of the femur. In the first year after it, mortality among patients can reach 20-24%. At the same time, it cannot be argued that all these deaths are directly caused by a fracture: the indicators are also influenced by old age, the state of health before the injury, immobility and concomitant diseases.
Calcium: is milk useful and how to replace it
Calcium remains one of the main elements of bone tissue. About 99% of its reserves in the body are found in bones and teeth. If there is not enough calcium, the body maintains its concentration in the blood using the reserves of the skeleton. With prolonged deficiency, it can contribute to bone weakening.
The need for calcium depends on age, gender, and health status. For example, the US National Institutes of Health recommend that most adults between the ages of 19 and 50 receive about 1,000 mg of calcium per day. For women over 50 years of age and people over 70 years of age, the indicator rises to 1.2 thousand mg. Norms in different countries may vary, and with diagnosed osteoporosis or concomitant diseases, the diet should be discussed with a doctor.
Milk, yogurt, and cheese are indeed convenient sources of calcium. A glass of milk contains about a quarter of an adult's daily requirement. In addition, dairy products provide the body with protein, phosphorus, and other substances involved in maintaining bone and muscle tissue.
The study, published in the journal BMJ, involved 7,195 elderly people who lived in Australian long-term care facilities. Increasing the amount of milk, yogurt, and cheese in the diet increased the intake of calcium and protein. In two years, the risk of hip fracture in this group was 46% lower, all fractures — by 33%, and falls — by 11% lower than in control institutions.
However, these results cannot be automatically distributed to all people. The participants were mostly very elderly patients who initially did not receive enough calcium and protein. The study shows the benefits of eliminating deficits in a particular group, but it does not prove that additional milk at any age protects against fractures by itself.
You can get calcium without dairy products. It is found in sardines and canned salmon with soft edible bones, tofu, certain types of cabbage, broccoli, almonds and fortified vegetable drinks. In the case of tofu, it is necessary to check the composition: the amount of calcium depends on the substance used to curdle soy milk. Herbal drinks also contain significant amounts of the mineral only if it was added by the manufacturer.
The calcium content in a product does not mean that the body will fully absorb it. Spinach contains a lot of oxalic acid, which binds the mineral and impairs its absorption. According to the US National Institutes of Health, about 5% of calcium is absorbed from spinach, and about 27% from milk. Kale, broccoli, and bok choy have higher bioavailability of calcium, although the mineral itself is usually less in a standard serving than in dairy products.
Why do bones need protein?
Bones and muscles should be considered as an interconnected system. Protein is necessary for the formation of the organic basis of bone tissue, and strong muscles maintain balance and reduce the likelihood of falling. For an elderly person, preventing falls can be no less important than changing bone mineral density.
Protein sources can be fish, meat, eggs, dairy products, legumes, soy, nuts and seeds. Products that combine several essential substances are especially useful. Sardines with bones contain protein and calcium, fatty fish contain protein and vitamin D, and tofu cooked with calcium salts combines vegetable protein with this mineral.
In case of kidney diseases and certain metabolic disorders, the amount of protein and calcium must be coordinated with the doctor. You should not switch to a high-protein diet on your own just for the sake of strengthening bones.
Soy, prunes and chia seeds: what research confirms
Soy products contain protein, and some types of tofu also contain significant amounts of calcium. In addition, soy contains isoflavones, plant compounds whose structure partly resembles estrogen.
Studies of isoflavone supplementation have shown small changes in bone mineral density in women after menopause, but the results remain mixed. A systematic review of five cohort studies has revealed a possible association between soy product consumption and a lower risk of fractures in Asian women, especially in the early years after menopause. No statistically significant relationship was found for men, and there is still insufficient data on residents of other regions.
Thus, soy can be considered as a full-fledged part of a varied diet, but not as a proven treatment for osteoporosis. Also, regular products should not be equated with concentrated additives with isoflavones.
Researchers are also interested in prunes. The annual randomized trial involved 235 postmenopausal women. In those who ate 50 grams of prunes daily, the femoral mineral density was practically preserved, whereas in the control group it decreased by about 1.1%.
At the same time, the study assessed bone density, not the number of fractures that occurred. Therefore, it is premature to say that prunes prevent fractures. It can be included in the diet as a source of fiber and plant compounds, but it does not replace calcium, protein, physical activity, or prescribed medication.
Chia seeds contain calcium, magnesium, phosphorus and polyunsaturated fatty acids. However, a widely cited study in which their long-term use was accompanied by an improvement in bone tissue parameters was conducted on laboratory rats. There is no reliable clinical data confirming a similar effect in humans yet. Chia seeds can supplement the diet, but they cannot be called a separate means of preventing osteoporosis.
Why Vitamin D is important
Vitamin D helps the body absorb calcium in the intestine and participates in muscle function. Its pronounced deficiency can lead to impaired bone mineralization and muscle weakness, which increases the risk of falls.
There are relatively few natural food sources of vitamin D. These include oily fish, including salmon, herring and mackerel, egg yolks, liver and some mushrooms. In a number of countries, vitamin D is additionally enriched in milk, herbal drinks, and prepared foods.
At the same time, the widespread idea that the preventive intake of vitamin D protects any healthy person from fractures has not been confirmed. The VITAL study involved 25,871 middle-aged and older people. Daily intake of 2,000 international units of vitamin D for more than five years did not reduce the incidence of total, extravertebral, or femoral fractures compared with placebo.
This result does not mean that the body does not need vitamin D or that the identified deficiency should not be corrected. The study participants were not specifically selected for deficiency, osteoporosis, or low bone density. The work shows something else: taking an additional vitamin without prescribed indications does not guarantee protection against fractures.
Special care should be taken with high doses. In one study, the annual intake of 500,000 international units of vitamin D by older women, on the contrary, increased the incidence of falls and fractures. The upper acceptable level of daily intake for most adults is 100 micrograms, or 4,000 international units. Higher therapeutic doses may be prescribed by a doctor for a limited period of time.
Do I need calcium and vitamin D supplements?
Getting calcium primarily from food is usually preferable. Foods simultaneously provide the body with protein and other nutrients, and calcium is supplied in small portions throughout the day.
Supplements may be needed by people who do not get enough calcium from food, avoid dairy products, have malabsorption, or are at increased risk. However, you should not take them just in case. Excess calcium can cause constipation and increase the likelihood of kidney stones, as well as interact with certain medications.
Data on the ability of calcium and vitamin D to prevent fractures in healthy adults living independently remain contradictory. The benefits may be more noticeable in elderly people in care settings, as well as in patients with confirmed nutritional deficiencies. Therefore, the decision on supplements should take into account the diet, test results, diseases and medications taken. Neither calcium, nor vitamin D, nor a single product can replace drug treatment for already diagnosed osteoporosis.
How to make a diet for bone health
The diet should regularly include sources of calcium, protein, and vitamin D, rather than focusing on a single "superfood." For example, a fermented milk product or fortified soy drink can be combined with nuts and fruits, fish, eggs, legumes or tofu can be added to main meals, as well as vegetables with well-absorbed calcium.
The amount of calcium should be checked on packages of herbal drinks and tofu. It is advisable to shake drinks before use, as the added mineral may settle at the bottom. Canned fish serves as a source of calcium only if its soft bones are eaten.
However, even a properly formulated diet does not solve the problem without exercise. To maintain bone mass, weight-bearing and resistance exercises are especially useful: walking, climbing stairs, dancing, and strength exercises. They simultaneously affect bones, strengthen muscles, and improve balance. If osteoporosis is diagnosed, the training program should be selected with a doctor or a specialist in physical therapy, since some movements may not be safe.
When do I need to check my bone density?
Osteoporosis is often referred to as a "silent" disease: there may be no noticeable symptoms until the first fracture. You should discuss the examination with your doctor after a fracture that occurred with a minor injury, prolonged use of glucocorticosteroids, early menopause, severe body weight deficiency, or the presence of a hip fracture in the parents.
Another alarming sign may be a decrease in height by more than 4 cm in adulthood or the appearance of pronounced stooping. Such changes are sometimes associated with compression fractures of the vertebrae, which are not always accompanied by severe pain.
The main principle of prevention remains quite simple: bone health is determined not by one product, but by a combination of proper nutrition, maintaining muscle strength, physical activity, quitting smoking and timely assessment of individual risk.
Переведено сервисом «Яндекс Переводчик»
