No matter your age, it’s never too soon – or too late – to start thinking about your bone health. After all, 1 in 2 women and up to 1 in 4 men will break a bone because of osteoporosis, a condition of weakened bones, during their lifetime. And while that’s most common later in life, the prime time to take action starts much earlier.
Although bones seem solid, they’re actually filled with small holes, like a knit sweater. And they don’t stay the same. The body constantly loses and forms bone tissue. More bone tissue means greater bone density – and stronger bones. But with age, bone loss outpaces bone formation. The holes grow larger as bone density fades.
While genes affect bone density, there are plenty of lifestyle habits that matter. For instance, the right approach to diet and exercise builds more bone and keeps you from losing too much.
What does it take to help protect bone mineral density? Here are answers from Andrea Singer, MD, the clinical director of the Bone Health & Osteoporosis Foundation. She’s also an associate professor, chief of the division of women’s primary care, and director of bone densitometry in the department of obstetrics and gynecology at MedStar Georgetown University Hospital in Washington, D.C.
This interview was edited for length and clarity.
What exactly is bone density and why is it important?
Singer: Bone density, also called bone mineral density (BMD), is the amount of minerals in a certain amount of bone. Bones are made from protein and minerals, such as calcium. Bones with more minerals are denser and stronger.
You build most of your bone density during childhood through [your] early 20s. By around 30, you’ve reached peak bone mass. In middle age, you start to lose bone density. Women experience the most loss during perimenopause and menopause. That’s because your body makes less of the hormone estrogen, which protects bones.
Low bone density can lead to osteoporosis and raise the risk for a fracture. For some, a broken bone can change their life. It can mean the difference between living independently and having to go to a nursing home.
What are the best kinds of exercise for bone density? Do walking and body weight exercises count, or does it need to be more high impact?
Singer: When we talk about an exercise prescription for bone health, there are three parts. The first is weight-bearing impact aerobic exercise, four to seven days a week. The bigger the force, the more your bone is stimulated to form new bone. High-impact exercises, like running and jumping, build bone density more than low-impact ones, such as walking or biking. But they all help, and some people aren’t able to do high-impact exercises.
The second is resistance training, two or more days a week. This includes free weights, weight machines, exercise bands, and body weight exercises. This puts stress on the bones to increase density, so it keeps muscles and bones strong.
The third component is 15 minutes of balance training, such as tai chi or standing on one leg, daily. This reduces the risk of falls. Of course, before you start any exercise program, you should talk with your health care practitioner first.
How much calcium should people get for their bone health, and do most need to take a supplement?
Singer: Your body doesn’t make calcium naturally, so you get it from food. If you don’t consume enough, calcium is taken from the bones.
- Women ages 50 and younger require 1,000 milligrams (mg) daily.
- Women over 50 require 1,200 mg per day.
- Men ages 70 and younger need 1,000 mg daily.
- Men over 70 should get 1,200 mg per day.
This amount includes both food and supplements. Ideally, people should get enough calcium from their diet. Any shortfalls are made up with supplements. There are calculators online where you can estimate how much calcium you’re getting from your diet.
Remember that more of the mineral isn’t always better. Too much calcium may cause constipation and kidney stones.
There are different types of calcium supplements. Each has their own nuances, so it’s a good idea to talk to your health care provider. For example, calcium carbonate is often the most affordable, and it’s best taken with food. Calcium citrate can be taken with or without food, and it’s less likely to cause kidney stones.
Vitamin D promotes bone health, but research on whether taking a D supplement protects against fractures is mixed. Should people take a vitamin D supplement?
Singer: This most recent data suggests that there’s no benefit in giving everyone across the board a vitamin D supplement. In other words, if someone has a sufficient amount of vitamin D, taking more isn’t going to give their bones extra protection.
The problem is that there are groups who are at risk for a vvitamin D deficiency, and they may need a supplement. Your body gets vitamin D from sunlight and some foods, so these groups include:
- Those who are homebound and tend not to go outside as much
- Those who don’t spend much time in the sun
- People with very dark skin
- Those with a condition that can interfere with vitamin absorption, such as celiac disease
If you fall into one of these groups – or think you may have a vitamin D deficiency – talk to your provider [about whether] you need a supplement. The Bone Health and Osteoporosis Foundation recommends that people under age 50 get 400 to 800 IU a day and 800 to 1,000 IU daily for those age 50 and above.
Most people think of dairy products as bone-building. What other foods are important for your bones?
Singer: With dairy, you get the biggest bang for your buck. It packs in the most calcium per serving. But there are many other foods with calcium, such as dark leafy greens and fortified nut milks and tofu. Canned fish with bones, such as sardines and salmon, are also calcium sources.
Besides calcium, people [should] make sure they’re getting enough protein. Your body uses protein to build bones, and many older people don’t get enough in their diet. The recommended dietary allowance is 0.8 grams per kilogram of body weight (0.36 grams per pound). For a 140-pound woman, that’s 50 grams per day. (Editor’s note: Some experts say this is too little, especially for older adults.)
The bottom line is that you should aim for a healthy, well-balanced diet with fruits, vegetables, and whole grains and an adequate amount of protein. These foods will supply other important nutrients for your bones, such as magnesium, vitamin K, and more.
What lifestyle habits are bad for your bones?
Singer: There are a few unhealthy habits that are problematic for bones.
Smoking cigarettes interferes with the way your bones absorb and use calcium. Research shows that it can lower bone mass, leaving it vulnerable to osteoporosis. This includes both smoking and secondhand exposure to cigarette smoke.
Excessive alcohol intake is another one. It can impair nutrient absorption, including calcium and vitamin D, and interrupt the bone-building process. The Bone Health and Osteoporosis Foundation recommends limiting alcohol to no more than two or three drinks a day.
(Editor’s note: The CDC defines moderate drinking as no more than one drink a day for women and no more than two drinks a day for men. A drink is defined as 12 ounces of beer with 5% alcohol, 8 ounces of malt liquor with 7% alcohol, 5 ounces of wine with 12% alcohol, or 1.5 ounces of liquor or distilled spirits (80-proof alcohol).
Eating a diet high in salt can also harm your bones. A diet high in sodium can increase calcium loss and affect bone reabsorption, so limit high-salt foods in your diet.
Some people have heard that carbonated or caffeinated drinks harm bone density. Is this true?
Singer: It’s not the carbonation that’s the problem. The concern is that the phosphoric acid that’s added to some sodas for flavor, such as cola, can leach calcium from bones. But that only happens with a significant amount of phosphoric acid. You’re not going to get that in a soda or two or three.
Caffeine is another issue. Very high amounts of caffeine – more than 500 milligrams (mg) per day – may interfere with calcium absorption. A 12-ounce can of cola contains 33 mg and an 8-ounce cup of coffee delivers 95 mg, so unless you’re sipping a lot of caffeinated drinks all day, you don’t need to worry.
When should you talk to your doctor about getting a bone mineral density screening?
Singer: The guideline is women should start getting a DEXA (dual X-ray absorptiometry) scan to measure bone density at age 65 and men at age 70. But people who have a risk factor for osteoporosis may need to get one earlier.
These include:
- People with a family history of osteoporosis or bone fractures
- Those who smoke or drink in excess
- Those who had an eating disorder or conditions that cause malabsorption, such as celiac disease.
People who take drugs that may cause bone loss, such as daily steroids for more than three months or certain hormone therapies for breast or prostate cancer, also fall into this group.
At what age should you start these habits? If you’re already older than that, is it too late to help your bones?
Singer: The earlier you get started, the better. It’s easier to prevent bone loss than to treat osteoporosis or a fracture.
And it’s never too late, either. Even if you’re older, taking these steps may help avoid further bone loss and delay or prevent osteoporosis.
If you already have osteoporosis, these healthy habits can help you grow bone, so you maintain or improve your bone density.
