21st Century Calcium 1200 mg + D3
Brand: 21st Century · Form: SOFTGEL CAPSULE [E0161]
Our assessment
The evidence shows that 21st Century Calcium 1200 mg + D3 provides a significant amount of calcium, a mineral essential for bone health. For most adults, the recommended daily allowance for calcium is 1,000 to 1,200 mg, so this supplement could help you meet your target, but it is important to account for calcium from your diet [NIH ODS].
How it works
Think of calcium as the primary building block for your skeleton. It supports bone density and mineral deposition through a process called bone mineralization. Beyond your bones, calcium also plays a key role in neuromuscular relaxation — it helps your muscles relax and your nerves send signals properly [NIH ODS].
Safety profile
FDA received 592,059 adverse event reports across all products, though this number is not specific to this supplement alone. Some research suggests that high calcium intakes might increase the risk of heart disease and prostate cancer. High levels can also cause constipation, nausea, weight loss, extreme tiredness, frequent need to urinate, abnormal heart rhythms, and a high risk of death from heart disease [NIH ODS]. Calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Start by calculating how much calcium you already get from food. If you are below 1,000 mg daily, this supplement may help. Take it with food and space it two hours apart from any thyroid medication or antibiotics to avoid absorption issues [NIH ODS]. Data not available on the specific vitamin D3 dose in this product, so consider your total vitamin D intake separately.
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | 21st Century |
|---|---|
| Serving Size | |
| Contents | 90.0 Softgel(s) |
| Market Status | Off Market |
How to Read This Label
Supplement labels contain several key sections regulated by the FDA:
- Serving Size — The recommended amount per dose. Always check this — some products require multiple capsules per serving.
- Amount Per Serving — Shows the quantity of each nutrient in the product, typically in IU (International Units), mg (milligrams), or mcg (micrograms).
- % Daily Value (%DV) — Indicates how much a nutrient in a serving contributes to a daily diet. 5% DV or less is low; 20% DV or more is high.
- Other Ingredients — Lists inactive ingredients like fillers, binders, and capsule materials (e.g., gelatin, cellulose, magnesium stearate).
- Suggested Use — The manufacturer's recommended directions for taking the supplement, including timing and dosage.
Source: FDA Dietary Supplement Labeling Guide