Menopause and osteoporosis

How is menopause linked to osteoporosis?

Normally, throughout life, the body keeps a balance between losing old bone and building new bone. Our bone mass reaches its peak at around the age of 30. After that, between the ages of 30 and 35, the body starts to lose bone mass faster than it can replace it.

Menopause is the time in a woman’s life when her periods stop (usually at around the age of 51). The ovaries stop producing oestrogen and progesterone, hormones that also help to keep bones strong. As a result, bone loss speeds up. Even during perimenopause (the 2 to 8 years before menopause), when the menstrual cycle starts to become irregular, oestrogen levels may begin to fall.

Ongoing bone loss over time leads first to osteopenia (reduced bone mass) and then to osteoporosis, a condition in which the bones become weak and fragile.

Which women are most at risk?

It’s important to start looking after your bones early. Your risk of bone loss is higher if there is a family history of osteopenia or osteoporosis, or if you:

• are white or of Asian origin
• are thin or have a small frame
• take steroid medicines (e.g. cortisone)
• have a diet low in calcium and vitamin D
• take little or no exercise
• smoke
• drink a lot of alcohol

You are also at risk if you have had both ovaries removed, if you do not have regular periods, or if you are past menopause (especially after the age of 65).

How is bone loss detected?

To check the strength of your bones, your doctor may ask you to have a bone density scan (bone mineral density measurement). The test gives accurate information about the density of the bone in the spine, the hip or sometimes the forearm.

The following should have a bone density scan:

• all women aged 65 and over, even if they have no risk factors;
• all postmenopausal women under 65 who have one or more risk factors;
• all postmenopausal women who have had a fracture.

Prevention and treatment

Lifestyle and diet play an important part in preventing and treating osteoporosis. Successful treatment, however, usually involves a combination of dietary supplements, medicines and lifestyle changes.

Calcium. All women over the age of 30–35 should be getting 1,200 mg of calcium a day. At the age of 50 (when menopause usually begins), intake should be 1,200–1,500 mg a day. Getting enough calcium takes a balanced diet that includes calcium-rich dairy products and, where needed, supplements.

Vitamin D. This is essential for absorbing calcium and building it into the bones. Sunlight produces vitamin D in the skin; other sources include fortified milk and cereals, egg yolks, fish and liver. Adults under 50 need 400–800 IU a day, and those over 50 need 800–1,000 IU a day.

Exercise. Daily physical activity, such as walking, strengthens the bones. A lack of exercise speeds up bone loss after menopause. At least 20 minutes of exercise a day can reduce bone loss.

Medicines. Many medicines can help to prevent or even reverse osteoporosis, when combined with calcium, vitamin D and exercise:

• bisphosphonates (alendronate, risedronate, ibandronate)
• raloxifene
• hormone therapy (oestrogen alone or, if the womb has not been removed, a combination of oestrogen and progesterone), in selected cases and for a short period of time
• analogues of human parathyroid hormone (teriparatide), for the treatment of severe osteoporosis
• calcitonin

All of these medicines are effective, but they can have side effects. Your doctor will work with you to choose the best treatment for you.

What does this mean for you?

Bone loss is a natural part of menopause, but that doesn’t mean you can’t keep your bones strong. A healthy lifestyle is the best place to start. The sooner you take steps to prevent it, the lower your risk of osteoporosis later on. If you already have risk factors, have a bone density scan.