The milk It is rich in calcium, good for bones or so they told us about girls. Then, as adults, we have been prescribed calcium supplements to prevent osteoporosis. Now they make us a mess, because new studies affirm that neither the high consumption of milk nor that of calcium supplements reduces, in adults, the risk of bone fractures. There are even those who claim that Excess of this mineral may increase the risk of heart attacks and probably prostate cancer in men.
Then what do we do? To get out of the vitiated circle of opinions and focus on scientific data, we have reviewed theor what the most rigorous studies say about it. This is a summary of their conclusions.
Taking too much calcium does not reduce the risk of osteoporosis in adults
In order to get the population to get the maximum amount of calcium absorbable by the bones (what is known as "maximum calcium retention"), health authorities recommend consuming 1,300 mg of calcium daily until age 19; 1,000 mg between the ages of 19 and 50; and 1,200 to 1,500 mg from the age of 50. The problem is that, to know how calcium consumption really affects the bone strength, long-term studies are needed. The very few that have been done so far indicate that a high calcium intake does not reduce the risk of osteoporosis. Research that has analyzed data from thousands of people have seen, in particular, that those who drink a glass of milk (or less) per week have no more risk of hip or forearm fracture than those who drink more milk.
We don't need so much
The specialists think about it when they see that, in countries such as India, Japan or Peru, where calcium consumption is barely 300 mg daily, the incidence of bone fractures is lower than in Europe or the USA. Although others should be taken into account factors (like more physical activity and / or more outdoor life), those variables they are not enough to explain the low incidence of fractures in those countries.
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- Cola drinks Older women who drink cola daily have less dense bones than those who drink them less than once a month, according to the Framingham study on Osteoporosis. It is believed that high levels of phosphorus in these soft drinks disrupt the calcium / phosphorus balance and weaken the bones.
- Excess protein Your body needs protein to make healthy bones, but by digesting it releases acids in the blood. How do you neutralize those acids? Well, extracting calcium from your bones. But there is controversy in this matter: some studies say that taking a lot of protein increases the risk of fractures and others conclude that it improves bone density. Be that as it may, moderation is the key.
- Vitamin A. Directs the process of extracting and replenishing calcium in the bones. That said, you have to be careful, because an excess of preformed vitamin A (retinol, present in liver, beef or poultry, whole milk and fortified foods) can favor bone fractures. That is why it is recommended to take vitamin A in the form of its precursor beta carotene, a plant antioxidant that does not increase the risk of fractures. Pumpkin, carrot, sweet potato, spinach, peaches, cantaloupe melon are rich in it …
- Alcohol consumption. It reduces estrogen levels in fertile women, which favors osteoporosis. It is also related to higher levels of cortisol, which reduces bone formation and stimulates its destruction.
- Tobacco It negatively affects the metabolism of calcium and vitamin D, and reduces estrogen levels. The worst consequence: it increases the risk of hip fractures by 50%, the most serious.
- The drugs. Just as there are drugs (such as corticosteroids) that favor the development of osteoporosis, there are those that help strengthen bones. As for hormone replacement therapy, it was no longer used to prevent osteoporosis when several studies showed that it increases the risk of stroke, thrombosis and breast cancer.
Bones are living tissues.
Throughout life, bones are being remodeled. Cells calls osteoclasts they destroy them, and cells called osteoblasts make them. If you are healthy, drink enough calcium and are physically active, the production will overcome destruction … but only up to 30 years. Afterwards, destruction is greater than production.
According to Spanish Society of Rheumatology, 80% of osteoporosis cases occur in women of postmenopausal age, due to the drop in estrogen levels. In our country, that means about two million women affected. In men, osteoporosis usually debuts later, because testosterone levels drop less rapidly than estrogen levels in women.
It is estimated that osteoporosis will cause a hip, wrist or vertebral fracture in half of women over 50. The quarter of the beds in the areas of traumatology of the hospitals Spaniards are occupied by people who have suffered osteoporotic fractures.
You can get vitamin D without taking supplements
Your body produces it when you expose the skin in the sun. Some 15 minutes daily Exposure in summer (without sun protection, which prevents its production) are sufficient. Then you have to protect yourself to avoid burns, skin cancer and other sun damage. If you have dark skin, you expose yourself little to the sun or live in areas with few hours of sun you may need a supplement of 2,000 IU (international units) daily of vitamin D. Talk to your doctor and ask if you should check your vitamin D levels.
Vitamin K is also essential
Present in the green leafy vegetables (such as lettuce, broccoli or kale) and natto (made with fermented soybeans), several studies with thousands of people have shown that women who consume a minimum of 110 micrograms of vitamin K per day They have a 30% lower risk of suffering a hip fracture than those that do not reach that amount. More specifically, women who took a daily ration of some green leafy vegetables had half the risk of hip fracture than those who only took one serving a week. Other studies have seen that vitamin K supplements improve biochemical processes related to bone health.
Vitamin D is vital
When calcium levels begin to decrease, the body stimulates the conversion of vitamin D to its active form that travels to the intestines to increase the calcium absorption by blood and to the kidneys to reduce their loss through urine. As proof of the importance of vitamin D, an analysis of clinical trials concluded that the consumption of 700 to 800 IU of said vitamin per day would reduce the risk of hip and non-vertebral fractures. Another similar has proven that vitamin D supplementation decreases the risk of falls in older people by one fifth. More recent research indicates that calcium supplements without vitamin D do not protect against the risk of fractures and may even increase the risk of heart attacks and prostate cancer.