NOW Magnesium & Calcium
Brand: NOW · Form: TABLET [E0155]
Our assessment
The evidence shows that a calcium and magnesium supplement like NOW Magnesium & Calcium can support bone health, but you need to be aware of specific risks and dosing guidelines. Calcium is essential for bone mineralization and neuromuscular relaxation [NIH ODS]. However, the data indicates that high calcium intakes might increase the risk of heart disease and prostate cancer, so you should not exceed recommended levels [NIH ODS].
How it works
Calcium works by supporting bone density and mineral deposition — think of it as the building block for your skeleton. It also helps your muscles relax and your nerves send signals properly [NIH ODS]. Magnesium plays a complementary role, though specific data on its mechanism from this product's ingredient list is not provided here.
Safety profile
FDA has received a total of 592,059 adverse event reports across all supplement categories. For calcium specifically, high levels 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]. Calcium supplements may also reduce the absorption of medications including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Start by reviewing your total calcium intake from food and supplements to stay within safe limits. If you take this product, take it at a separate time from any prescription medications listed in the interactions. Data not available on the exact dosage per serving for this specific product, so check the label carefully. For most adults, the goal is to meet — not exceed — your daily calcium needs through a balanced diet [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | NOW |
|---|---|
| Serving Size | |
| Contents | 100.0 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