Calcium Supplement Guide
Evidence-based information on Calcium benefits, dosage, safety, and food sources — sourced from NIH, FDA, and PubMed.
Our assessment
The evidence shows that calcium is a critical mineral for bone health, but it is not without risks. Our assessment is that you should focus on meeting your calcium needs through food first, and only use supplements under specific guidance, as high intakes carry real safety concerns NIH ODS ↗.
How it works
Think of calcium as the building block for your skeleton. It supports bone density and mineral deposition, which is essential for keeping your bones strong. Calcium also plays a key role in neuromuscular relaxation, helping your muscles relax and your nerves signal properly after they fire NIH ODS ↗.
Safety profile
The FDA has received a total of 592,059 adverse event reports for calcium supplements. This is a significant number that warrants caution. Some research suggests that high calcium intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in the blood and urine can cause poor muscle tone, poor kidney function, low phosphate levels, constipation, nausea, weight loss, extreme tiredness, frequent need to urinate, abnormal heart rhythms, and a high risk of death from heart disease FDA FAERS ↗ NIH ODS ↗.
Our recommendation
Our recommendation is to prioritize dietary calcium from sources like dairy, leafy greens, and fortified foods. If you do use a supplement, do not exceed the RDA without a doctor’s supervision. Be aware that calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin, so take them at separate times NIH ODS ↗.
AI-assisted analysis based on NIH ODS, FDA, and PubMed data. Citations are linked to original sources.
Recommended Dosage
| Age | Male | Female | Pregnant | Lactating |
|---|---|---|---|---|
| 0-6 months* | 200 mg | 200 mg | ||
| 7-12 months* | 260 mg | 260 mg | ||
| 1-3 years | 700 mg | 700 mg | ||
| 4-8 years | 1,000 mg | 1,000 mg | ||
| 9-13 years | 1,300 mg | 1,300 mg | ||
| 14-18 years | 1,300 mg | 1,300 mg | 1,300 mg | 1,300 mg |
| 19-50 years | 1,000 mg | 1,000 mg | 1,000 mg | 1,000 mg |
| 51-70 years | 1,000 mg | 1,200 mg | ||
| >70 years | 1,200 mg | 1,200 mg |
Source: National Academies of Sciences, Engineering, and Medicine. Always consult your healthcare provider for personalized dosage recommendations.
Drug Interactions
Calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin. Calcium supplements may also reduce the absorption of iron and zinc. Proton pump inhibitors, loop diuretics, and corticosteroids can decrease calcium absorption.
Check All InteractionsFood Sources
Milk, yogurt, and cheese are rich natural sources of calcium. Nondairy sources include canned sardines and salmon with bones as well as certain vegetables, such as kale, broccoli, and Chinese cabbage. Foods fortified with calcium include many fruit juices and drinks, milk substitutes (e.g., soy and almond beverages), tofu, and ready-to-eat cereals.
Complete food source guideClinical Evidence
Calcium has been studied in 3+ clinical studies:
Dietary supplement consumption among active individuals in Saudi Arabia.Alsayegh AA · 2026
Patient Perceptions of Dietary Supplement Use and Kidney Stone Disease.Kim DD · 2026
Dietary supplement and medication use in professional and pre-professional dancers: widespread use b...Vela-Andreu M · 2026
Health Goals This Supplement Supports
Frequently Asked Questions
What are the benefits of Calcium?
Calcium is essential for bone health. Adequate calcium intake throughout life helps reduce the risk of osteoporosis. Calcium may also help reduce the risk of colorectal cancer and help manage blood pressure.
How much Calcium should I take daily?
Refer to the Recommended Dosage table above. Individual needs vary by age, gender, and health status. Always follow the dosage on your supplement label and consult your healthcare provider.
What are the side effects of Calcium?
Some research suggests that high calcium intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in the blood and urine can cause poor muscle tone, poor kidney function, low phosphate levels, constipation, nausea , weight loss, extreme tiredness, frequent need to urinate, abnormal heart rhythms , and a high risk of death from heart disease. However, high levels
Can I get enough Calcium from food alone?
Milk, yogurt, and cheese are rich natural sources of calcium. Nondairy sources include canned sardines and salmon with bones as well as certain vegetables, such as kale, broccoli, and Chinese cabbage. Foods fortified with calcium include many fruit juices and drinks, milk substitutes (e.g., soy and
Does Calcium interact with medications?
Calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin. Calcium supplements may also reduce the absorption of iron and zinc. Proton pump inhibitors, loop diuretics, and corticosteroids c
Key Takeaways
Medical Disclaimer: The information on this site is for informational purposes only and is not a substitute for professional medical advice. Always consult your healthcare provider before starting any supplement regimen.
FDA Disclaimer: * These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.