21st Century 600 Calcium Supplement
Brand: 21st Century · Form: TABLET [E0155]
Our assessment
The evidence shows that calcium is a critical mineral for your bone health, but it requires careful dosing. For the 21st Century 600 Calcium Supplement, the data confirms that 600 mg of calcium can help you meet your daily needs, though you must account for total intake from food and other supplements [NIH ODS].
How it works
Think of calcium as the building block for your skeleton. It supports bone mineralization and density, and it also helps your muscles relax and your nerves send signals properly [NIH ODS].
Safety profile
FDA received 592,059 total adverse event reports for products in this category. You should be aware that high calcium intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in your 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 [NIH ODS] [FDA data]. Calcium can also reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Start by assessing your total daily calcium intake from all sources. Since this supplement provides 600 mg, you may need additional calcium from food or a second dose if your target is 1,000–1,200 mg daily. Take it with food for better absorption, and separate it from any medications listed above by at least two hours [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | 21st Century |
|---|---|
| Serving Size | |
| Contents | 400.0 Tablet(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