Calcium 500 mg + vitamin D3
Useful when food does not get there, especially after 50. Not a reflex for everyone.
The short version
What it does It tops up an insufficient dietary intake, for bone.
What it does not do It acts neither on muscle, nor on cartilage, nor on joint pain. And it increases the risk of kidney stones: reserve it for genuinely low intakes.
What the studies say
Jackson’s trial, within the Women’s Health Initiative, tested calcium and vitamin D in postmenopausal women: a slight improvement in hip bone density, with no significant fracture reduction in the trial’s general population — but with a benefit in women who actually took their treatment. Martineau separately confirms the value of correcting vitamin D deficiency.
The trial also observed an increase in kidney stones. Supplemental calcium is not harmless, and the cardiovascular risk data has been debated.
To be reserved for people whose dietary intake is genuinely insufficient. Food remains superior to the tablet.
How to take it
Relevant after the menopause, in documented osteoporosis, or on a dairy-free diet with low intake. Pointless if you already eat dairy, calcium-rich waters, almonds or green vegetables in quantity.
Work out your dietary intake first: the goal is a total of 1,000 to 1,200 mg a day, supplement INCLUDED. Split into doses of 500 mg maximum — beyond that, absorption falls. With a meal. Never at the same time as iron.
The useful marker is a bone density scan, not a sensation. With a history of kidney stones, discuss it with a doctor first.
What is inside
Calcium carbonate is the cheapest and contains the most elemental calcium, but it needs stomach acid: it must be taken during a meal, and it is poorly absorbed on a proton pump inhibitor. Calcium citrate absorbs independently of acidity, but contains less calcium per tablet.
Citrate if you take an antacid or are over 65. Carbonate otherwise, with a meal. Read the dose as ELEMENTAL calcium.
Single doses above 500 mg, and combining with iron in the same dose. History of stones: medical advice is mandatory.
Cautions
- History of kidney stones
- Hypercalcaemia
- Leave 2 h around iron and certain antibiotics
The three options
Citrate + D3, splittable
Citrate: absorbs without acidity
Useful after 60 or on antacid treatment, when the stomach is less acidic. 533 mg of elemental calcium in two capsules, which lets you split the dose.
For whom — Over 65, or on antacid treatment.
Carbonate + D3
Three ingredients, 800 mg
Calcium carbonate, cellulose, cholecalciferol. 180 tablets, 2,266 reviews. Carbonate needs acidity to absorb: take it during a meal, never on an empty stomach.
For whom — Everyday use if dietary intake is insufficient.
Citrate too, in a gelatin capsule
The cheapest, and the list is clean
Calcium citrate, vitamin D3 and vitamin K1, 90 capsules. The same form as the premium option — the one that absorbs without stomach acid — for considerably less. Two differences to know: the capsule is gelatin, so it is not vegan, and it is K1, not K2 MK-7. Carries “may contain soya and gluten”.
For whom — The lowest price, giving up nothing on the calcium form.
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