There’s a reason your mother nagged you to drink your milk. What you put into your body strongly influences the health of your bones, not only when you’re a kid but also for the rest of your life. While some substances — such as the calcium found in a frosty, tall glass of milk — strengthen bones, others, such as excessive amounts of alcohol, can deplete them.

If you think of your bones as a bank, you’ll recognize the importance of making regular deposits when you’re young (and encouraging your kids to do so). In your thirties, your body starts to make more withdrawals than deposits, reducing some of your skeletal nest egg.

At that point, it’s impossible to make enough deposits to increase your peak bone mass. But with the right diet choices, you can slow or potentially stop your bones from becoming thinner and weaker, even if you’ve already shown significant bone loss.

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What’s Best for Your Bones?

Try This

If you’re lactose intolerant or you don’t like regular milk, buy calcium-fortified orange juice or soy milk. When paired with calcium-rich fish or vegetables, you should be able to reach the recommended daily dose.

Count on Calcium
Calcium is an essential mineral for building strong, dense bones. Too little calcium is associated with low bone mass and a higher risk of fractures. Yet nutrition surveys show that many Americans don’t get enough calcium. Milk and other dairy products are the best sources, but many other foods, including herring, salmon, spinach, kale and tofu, are also calcium rich. (Cod liver oil is too, so that’s why your mother may have also nagged you about that.)

How much calcium you need depends on your age and gender: People over 50, kids ages 9 through 18, and pregnant and breast-feeding women need the most. If you have osteoporosis or osteopenia, your doctor is likely to encourage you to take a calcium supplement to be sure you’re getting enough.

Don’t Forget Your D
Known as the sunshine vitamin because it is formed in our bodies after exposure to the sun, vitamin D helps with calcium absorption. A lack of D has been linked to osteoporosis in adults. Vitamin D deficiency is a growing problem in the United States, with studies suggesting that at least one-third of seemingly healthy young adults have low D levels in their blood. It’s difficult to get enough D from our diets because it is found in just a few foods, including certain fish (among them salmon, tuna and sardines), egg yolks and fortified milk.

People who live in northern, cloudier locales also tend to have lower D levels. Federal health officials recommend that adults under age 50 should get at least 200 IU of vitamin D a day, while people 50 and older should aim for 400 to 600 IU. But many experts, including the president of the National Osteoporosis Foundation, believe those numbers are too low and encourage healthy adults to get 1,000 IU a day. The vitamin can be found at your pharmacy and is often taken alongside a calcium supplement.

VIDEO: The Connection between Vitamin D and Bone Renewal

Estrogen on a Plate
The word phytoestrogens may be hard to swallow, but foods containing them should be part of your diet. These plant compounds mimic estrogen in the body — a hormone that protects bones. In southeast Asia, where diets are high in phytoestrogens, hip fracture rates are generally lower.

In the United States, there is growing interest in boosting consumption of phytoestrogens, especially for women after menopause, as hormone-replacement therapy has waned in the wake of studies linking it with breast cancer. Chickpeas, cereal bran, tofu, alfalfa, legumes and soy products are good sources of phytoestrogens. A synthetic form, ipriflavone, may have some protective effects on bones but is not recommended because of safety concerns and a general lack of evidence that it works. 

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What’s Bad for Your Bones?

Being Too Skinny
Yes, there is such a thing as being too thin. It raises the risk of developing osteoporosis and, if you have it, of breaking a bone if you fall. Eating disorders such as anorexia and bulimia, which often result in dangerously low intake of calcium and vitamin D, are especially harmful for bones. In a British study of patients with a history of anorexia, nearly one-third had osteoporosis and half had below-average bone mass.

Having That Extra Drink
A mojito or mai tai would seem to have little to do with your skeletal structure. But next time you belly up to the bar, consider this: Excessive drinking decreases bone mass. Research at Loyola University suggests that large amounts of alcohol may disrupt the molecular pathways involved in normal bone metabolism. And, of course, getting tipsy can also lead to a bone-breaking fall. How much is too much? Federal health officials say women should limit themselves to one drink a day, and men should stop at two. That goes for beer and wine as well as hard liquor.

Revving Up on Caffeine
You don’t have to give up your cola and cappuccino entirely, but go easy. Coffee and many soft drinks contain caffeine, and soda also contains phosphorus; both substances can interfere with the body’s supply and storage of calcium.

A Tufts University study suggested that phosphoric acid in soda blocks the body from absorbing calcium. If you must drink that third or forth cup of joe or you can’t resist that supersized soda, be sure to get additional calcium in your diet, says Chad Deal, MD, head of the Center for Osteoporosis and Metabolic Bone Disease at the Cleveland Clinic.

If your idea of a good meal includes an after-dinner cigarette, it’s time to change your thinking. Most smokers are aware that their habit can cause lung cancer, emphysema, wrinkled skin and bad breath. But brittle bones? Believe it.

Scientists are trying to understand exactly how smoking affects bone density. But studies show that longtime smokers experience more bone loss, have a greater risk of developing bone fractures and can take longer to heal than nonsmokers.

by Julie Sevrens Lyons