Supplements for Bone Health

A quick, evidence-based guide for osteopenia & osteoporosis

The goal is strong bones without overdoing it. Food comes first; supplements are meant to fill the gap between what you eat and what your bones need, not to pile on. More is not always better. Use this guide as a starting point.

1. Calcium: aim for a total, mostly from food

Daily target (food + supplements combined): 1,200 mg for women 51+ and everyone 71+; 1,000 mg for men 51–70.

• Food first. Roughly 300 mg per serving of dairy or fortified plant milk. Other good sources: canned salmon or sardines with bones, tofu set with calcium, fortified orange juice, and leafy greens (collard greens, bok choy).
• Supplement only the gap. Add up your usual food sources; most people need only 500–600 mg from a supplement, and some need none.
• Take it in smaller doses. Your body absorbs 500–600 mg of elemental calcium at a time. If you need more, split it — e.g., one dose at breakfast, one at dinner.
• Read “elemental” calcium on the label. That is the number that counts. Calcium citrate absorbs well with or without food and is gentler on the stomach — a good choice if you take acid reducers or get constipated. Calcium carbonate is fine too but should be taken with meals.

2. Vitamin D: the partner that makes calcium work

Typical dose for bone health: 800–1,000 IU of vitamin D3 per day. Vitamin D helps your body actually absorb the calcium you take in.

• We aim for a blood level (25-OH vitamin D) of about 30–50 ng/mL. If yours is low or you’re not sure, you can talk with your primary care physician about checking a level and adjusting the dose.
• Daily dosing is preferred over large weekly or monthly doses. Stay at or below 4,000 IU/day unless specifically prescribed otherwise.
• Some formulas add vitamin K2, which may help steer calcium into bone. It’s generally safe — but if you take warfarin or another blood thinner, check with your doctor first, since vitamin K interacts with those medications.

3. Protein: the scaffolding bones are built on

Aim for 1.0–1.2 grams of protein per kilogram of body weight per day because it protects both muscle and bone as we age.

• Quick math: a 150-lb (68 kg) person needs about 70–80 g of protein a day — roughly 25–30 g at each meal.
• Easy sources: eggs, Greek yogurt, cottage cheese, fish, poultry, beans and lentils, tofu, and dairy. Spreading protein across all three meals works better than one big serving.

4. Collagen: optional, promising, not a substitute

• A 12-month randomized trial found that 5 g/day of specific collagen peptides modestly improved bone density in postmenopausal women. The evidence is encouraging but still limited.
• If you enjoy it, it’s reasonable to add — and it counts toward your protein for the day. Just don’t let it replace the essentials: calcium, vitamin D, protein, and exercise!

Examples of good formulations

These are solid, third-party–quality options I trust, examples of what to look for, not the only choices. Any reputable brand with clear “elemental” calcium and D3 works.

• Calcium: Pure Encapsulations Calcium (Citrate) — 150 mg elemental calcium per capsule. Citrate form, so it absorbs with or without food; the low per-capsule dose makes it easy to fine-tune to your gap.
• Vitamin D: NOW Vitamin D-3 & K-2 — 1,000 IU (25 mcg) D3 plus 45 mcg K2 per capsule. (Remember the warfarin/blood-thinner note above if that applies to you.)

Quick answers to common questions

“Can I just take one big pill for everything?”  Usually not ideal — calcium absorbs best in smaller, split doses, and combo pills often under- or over-shoot. It’s fine to take calcium and vitamin D together.

“What time of day?”  Calcium citrate: anytime. Calcium carbonate: with meals. Vitamin D: with a meal that has some fat helps absorption.

“Do I still need supplements if I eat well and get sun?”  Many people do hit calcium through diet. Vitamin D is harder to get from food and sun alone, so a daily D3 is often still worth it.

This article is general education based on guidance from the NIH Office of Dietary Supplements, the 2024 Endocrine Society vitamin D guideline, the International Osteoporosis Foundation, and PROT-AGE/ESPEN protein recommendations. It does not replace individualized discussions. Talk to your physician or pharmacist before starting or changing supplements, especially if you have kidney disease, a history of kidney stones, or take other medications.