Source Naturals Calcium
Brand: Source Naturals · Form: TABLET [E0155] On Market
Our assessment
The evidence shows that calcium is a foundational mineral for your bone health, but you need to be careful with dosing. While the ingredient is well-studied, the data on high intakes raises important safety questions that you should discuss with your doctor before starting this supplement [NIH ODS].
How it works
Think of calcium as the building block for your skeleton. It supports bone density and mineral deposition, which is critical for preventing fractures as you age. Beyond bones, calcium plays a key role in neuromuscular relaxation, helping your muscles relax and your nerves send signals properly [NIH ODS].
Safety profile
FDA received a total of 592,059 adverse event reports for this product category. The data shows that high calcium intakes might increase the risk of heart disease and prostate cancer. Specific side effects from high levels in the blood and urine include 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 data] [NIH ODS].
Our recommendation
Start by checking your total daily calcium intake from food and other supplements. Do not exceed the tolerable upper intake level without medical supervision. Also, be aware that calcium can reduce absorption of medications like bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin, so take your supplement at a different time of day than these drugs [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | Source Naturals |
|---|---|
| Serving Size | |
| Contents | 250.0 Tablet(s) |
| Market Status | On 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