How Do You Keep Your Bones Healthy After 40?

After 40, the main ways to keep your bones healthy are getting enough calcium (1,000 mg a day for most adults in the US, rising to 1,200 mg for women over 50 and everyone over 70), keeping vitamin D at a normal level, and doing weight-bearing and strength exercise most days. Not smoking and keeping alcohol low matter too, because after your mid 30s you slowly lose more bone than you make.

When does bone loss start?

Bone is living tissue that is broken down and rebuilt all the time. Through childhood and your 20s, building wins, and most people reach their peak bone mass around age 30. For roughly the next decade things stay fairly even. Then, from somewhere in your late 30s or 40s, breakdown slowly gets ahead.

In men the decline is gradual and steady. In women it speeds up sharply for several years around menopause and then settles back to a slower pace. That is the main reason osteoporosis is far more common in women, although men get it too, and men who break a hip tend to do worse afterward.

You cannot feel any of this. Thinning bones do not hurt. The goal after 40 is to hold on to what you have and slow the rate of loss, so that a trip on the curb at 75 means a bruise rather than a broken hip.

How much calcium and vitamin D do you need after 40?

Calcium targets differ a little between countries. The US uses higher figures than the UK, where the NHS advises 700 mg a day for adults. Both agree that more is not better past a point.

Group (US)	Calcium per day	Upper limit
Men and women, 19 to 50	1,000 mg	2,500 mg
Men, 51 to 70	1,000 mg	2,000 mg
Women, 51 to 70	1,200 mg	2,000 mg
Everyone, 71 and older	1,200 mg	2,000 mg

Food is the best source, because your body absorbs calcium best in smaller amounts spread through the day. A glass of milk (8 ounces) has about 300 mg. So does an 8-ounce pot of plain yogurt, often a bit more. An ounce and a half of cheddar gives around 300 mg, a 3-ounce serving of canned sardines with the bones about 325 mg, and a cup of cooked kale somewhere around 100 to 180 mg depending on how it is prepared. Calcium-set tofu and fortified plant milks can be good sources too; check the label. Spinach looks rich on paper, but very little of its calcium is absorbed.

If you take a supplement, take no more than 500 to 600 mg at once and count what you already eat. Very high intakes from pills have been linked to kidney stones and constipation, and there is an ongoing debate about whether high-dose calcium supplements affect heart risk. The evidence there is mixed.

Vitamin D lets your gut absorb calcium. The US recommends 600 IU (15 micrograms) a day up to age 70 and 800 IU (20 micrograms) after that, with an upper limit of 4,000 IU (100 micrograms). The NHS advises everyone in the UK to consider 10 micrograms a day in autumn and winter, when sunlight is too weak to make enough. Oily fish, egg yolks and fortified foods contain some, but few people get enough from diet alone. Too much vitamin D over time can raise calcium in the blood, so megadoses are not a shortcut.

What exercise is best for bone density?

Bone responds to load. When muscles pull on bone and your body weight jars it, the bone gets a signal to stay strong. Two kinds of exercise do this best:

• Weight-bearing exercise, where your feet and legs carry your weight: brisk walking, hiking, stair climbing, jogging, dancing, tennis.
• Resistance exercise, where muscles work against a load: lifting weights, using bands or machines, push-ups, squats.

Swimming and cycling are great for your heart and joints, but because the water or the bike takes your weight, they do little for bone. If they are your main activities, add some walking and strength work.

Aim for strength exercises on at least two days a week and some weight-bearing activity on most days. For people who already have healthy bones and no joint problems, adding short bursts of impact, such as a few minutes of skipping or brisk stair climbing, gives the hip extra stimulus. Supervised high-intensity strength programs have improved bone density in some trials of women with low bone mass, but they were small and closely supervised, so do not jump to heavy lifting on your own.

Balance work belongs here too. Most hip fractures happen because of a fall, so staying steady on your feet protects your bones as much as density does.

Smoking, alcohol and other habits that thin bones

Smoking is linked to lower bone density and a higher risk of fractures, including hip fractures. It also slows fracture healing. Stopping at any age helps.

Alcohol is about dose. Regularly drinking more than about two drinks a day, or more than the UK limit of 14 units a week, is linked to bone loss and many more falls. Light drinking does not appear to cause the same problem.

Being underweight is a risk factor that people often miss. A body mass index under about 19, or a history of an eating disorder, means less bone to start with. Long-term use of steroid tablets, some epilepsy drugs, certain breast and prostate cancer treatments and long-term use of stomach acid medicines can also affect bone. Do not stop a prescribed medicine on your own; ask whether your bones need monitoring instead.

How does menopause affect your bones?

Estrogen helps slow the breakdown of bone. When estrogen falls at menopause, that brake comes off. Studies that have followed women through the change show the fastest loss in the few years around the final period, after which it slows again.

Women who reach menopause before 45, or who have their ovaries removed, lose that protection earlier and carry a higher risk. Hormone therapy reduces bone loss and fractures while it is being taken, but it is usually chosen to treat menopausal symptoms, with bone as a side benefit, because it has its own risks to weigh. That is a conversation to have with your doctor.

Men see a slower version of the same effect as testosterone gradually declines. Low testosterone from other causes can thin bone faster.

Who should get a bone density scan?

The standard test is a DEXA scan, a quick, painless X-ray of the hip and spine that uses a very low radiation dose. The result is given as a T-score, which compares your bones with those of a healthy young adult. A score of -1 or above is normal, between -1 and -2.5 is low bone mass (often called osteopenia), and -2.5 or below is osteoporosis.

In the US, screening is recommended for all women 65 and older, and for younger postmenopausal women whose risk is raised by factors such as low body weight, smoking, heavy drinking or a parent who broke a hip. For men, expert bodies disagree on routine screening, but many clinicians consider it from age 70, or earlier with risk factors.

In the UK there is no routine screening program. The NHS offers a scan when a risk calculation, a fracture after a minor fall, or other risk factors suggest it is needed.

When should you see a doctor?

Osteoporosis is often called silent because the first sign is frequently a broken bone. See a doctor if you notice:

• A fracture from a minor fall or bump, such as falling from standing height and breaking a wrist
• Losing height, especially 1.5 inches (about 4 cm) or more from your adult height
• A stooped or curved upper back that is getting worse
• Sudden back pain with no clear cause, which can be a small fracture in the spine

Ask about your bone health even without symptoms if you went through menopause before 45, have taken steroid tablets for three months or more, have rheumatoid arthritis, celiac disease, an overactive thyroid or kidney disease, or have a parent who broke a hip.

Check with a doctor or pharmacist before taking calcium or vitamin D supplements if you have had kidney stones, have kidney disease, or take thyroid medicine, certain antibiotics or osteoporosis drugs, since calcium can block their absorption and they may need to be taken hours apart.

Frequently asked questions

Can you rebuild bone after 40?

Exercise and good nutrition can slow loss and, in some trials, raise bone density by a few percent, but they do not fully reverse osteoporosis. Prescription treatments can increase density more clearly and lower fracture risk. Lifestyle steps still matter alongside any medicine.

Is coffee bad for your bones?

Moderate amounts, around three to four cups a day, do not appear to harm bone in people who get enough calcium. Caffeine causes a small calcium loss in urine, so very high intakes combined with low calcium may be a problem.

Does osteopenia mean you will get osteoporosis?

Not necessarily. Osteopenia means your bone density is below the young adult average, which is common with age. Your doctor will look at your overall fracture risk, not just the score, to decide whether treatment or just a repeat scan in a few years makes sense.

Are men at risk of osteoporosis too?

Yes. Around one in five men over 50 will break a bone because of osteoporosis, according to commonly cited estimates. Men are less likely to be tested, so a fracture after a small fall should prompt a check.