21st Century 600+D3 Calcium Supplement
Brand: 21st Century · Form: TABLET [E0155]
Our assessment
The evidence shows that calcium is a critical mineral for your body, and the 21st Century 600+D3 Calcium Supplement provides a strong dose of 600 mg per serving. However, you need to be careful with total daily intake from all sources, including food and other supplements, because high calcium intakes may increase the risk of heart disease and prostate cancer [NIH ODS].
How it works
Think of calcium as a structural builder and a messenger. It supports bone density and mineral deposition, which is essential for keeping your skeleton strong. It also plays a key role in neuromuscular relaxation, helping your muscles relax and your nerves signal properly [NIH ODS].
Safety profile
FDA received a total of 592,059 adverse event reports across all supplement categories, but specific report counts for this product are not available. From the data, 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 [NIH ODS] [FDA data]. Additionally, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
You should take this supplement only if your total daily calcium intake from food and other sources does not exceed the recommended amount. Take it at a different time than any medications listed in the interactions above. If you have a history of kidney disease, heart disease, or prostate cancer, consult your doctor before starting [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | 21st Century |
|---|---|
| Serving Size | |
| Contents | 75.0 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