NOW Magnesium Citrate
Brand: NOW · Form: CAPSULE [E0159] On Market
Our assessment
The evidence shows that this product contains calcium, which is a mineral critical for bone health. Our assessment is that while calcium is essential, you need to be careful with dosage because high intakes carry specific risks. Data on the exact dosage and form in this specific product is not available, so you should compare this to your total daily intake from food and other supplements [NIH ODS].
How it works
Think of calcium as a structural builder for your bones and a signal regulator for your nerves and muscles. It supports bone density and mineral deposition, and it also helps your muscles relax and your nerves send signals properly [NIH ODS].
Safety profile
The FDA has received a total of 592,059 adverse event reports for this product category. For calcium specifically, high intakes might increase the risk of heart disease and prostate cancer. Very high levels 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 [FDA data] [NIH ODS]. Calcium can also reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
We recommend you first assess your total daily calcium intake from food. Do not exceed the Tolerable Upper Intake Level without medical supervision. Because calcium can interact with many common medications, take this supplement at least two hours apart from those drugs. Since data on the specific dosage is not available, start with the lowest effective amount and consult your doctor before adding this to your regimen [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | NOW |
|---|---|
| Serving Size | |
| Contents | 120.0 Veg Capsule(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