Calcium is the primary mineral that gives bone its strength and density. Approximately 99 percent of the body's calcium is stored in the skeleton. This means bone is both the source and the storage site when calcium is needed elsewhere. When dietary calcium is inadequate, the body draws on bone reserves to maintain blood calcium levels, gradually depleting density over time.

This is why calcium intake matters. Not as a cure for osteoporosis, but as a foundation without which everything else works less effectively.

CALLOUT: Calcium is not a treatment for osteoporosis on its own. But without adequate calcium, osteoporosis medications and exercise have less to work with. Think of calcium as the raw material and treatment as the process that makes use of it.

How much do you need?

Calcium requirements increase after menopause because estrogen loss reduces the efficiency with which the gut absorbs calcium from food. The body compensates partly by drawing more calcium from bone, which accelerates the bone loss already triggered by lower estrogen.

General international evidence supports the following daily targets:

  • Women aged 19–50: approximately 1,000mg per day
  • Women over 50 (post-menopausal): approximately 1,200mg per day
  • Women over 70: 1,200mg per day, with some evidence supporting slightly higher intakes

These figures represent total calcium from all sources - food and supplements combined.

CALLOUT: Most women get approximately 700–800mg of calcium per day from food alone, which means many post-menopausal women are falling short of their daily target without realising it. A quick review of your daily diet often reveals where the gap is.

Spread your intake through the day

The body can only absorb a limited amount of calcium at one time. This is typically around 500mg per dose. Taking a large supplement all at once is less effective than spreading intake across the day. If you are supplementing, taking 500mg at breakfast and 500mg at dinner, alongside dietary calcium, is more efficient than a single large dose.

Can you have too much calcium?

Yes, and this is worth understanding. Very high calcium intake, such as consistently above 2,500mg per day from all sources combined, has been associated with potential risks including kidney stones in susceptible individuals and, in some studies, possible cardiovascular effects with high-dose supplementation.

The key message is not to over-supplement. If your diet already provides 800–1,000mg per day, a supplement of 200–400mg may be all you need, not 1,200mg on top of your food intake.

CALLOUT: Before adding a calcium supplement, it is worth estimating how much calcium you are already getting from food. The next article in this section (on food sources of calcium) will help you do that. Many women find they need less supplementation than they assumed.

Food first, supplements second

The current evidence suggests that calcium from food is preferable to calcium from supplements where possible. Food sources of calcium come packaged with other nutrients such as protein, vitamin K, magnesium. These support bone health in ways that isolated supplements do not. Supplements are a useful safety net, not a replacement for dietary calcium.

QUOTE: "The goal is not to take a tablet and consider the job done. It is to build a diet that provides the foundation your bones need and to fill the remaining gap with supplementation where necessary."