NOW Calcium Citrate
Brand: NOW · Form: TABLET [E0155]
Our assessment
Our assessment: For bone health, calcium is essential, but the evidence shows that more is not always better. The data indicates that while calcium is critical for bone mineralization, some research suggests that high intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. You should aim to get your daily needs met primarily through diet, and only use a supplement like this one to fill a verified gap.
How it works
Think of calcium as the structural building block for your skeleton. It supports bone density and mineral deposition, and it also plays a key role in neuromuscular relaxation and nerve signaling [NIH ODS]. This means it helps your muscles relax after contracting and your nerves transmit messages properly. Without enough calcium, your body will leach it from your bones to support these vital functions.
Safety profile
The FDA has received a total of 592,059 adverse event reports for calcium-containing products. 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]. Crucially, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Start by evaluating your total calcium intake from food. The data confirms that high calcium intakes might increase the risk of heart disease and prostate cancer, so avoid taking this supplement unless you have a confirmed deficiency [NIH ODS]. Take calcium citrate with food to improve absorption, and separate it from any of the medications listed above by at least 2 hours [NIH ODS]. Data not available for specific dosing from this product's label.
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | NOW |
|---|---|
| Serving Size | |
| Contents | 250.0 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