NOW Probiotic Defense
Brand: NOW · Form: CAPSULE [E0159]
Our assessment
The evidence shows that calcium is a critical mineral for bone health, but it requires careful management. Our assessment: based on the data, you should only supplement calcium if you cannot meet your needs through diet, and you must be aware of the potential risks at high intakes [NIH ODS].
How it works
Think of calcium as a structural builder for your bones and a signal messenger for your nerves. It supports bone density and mineral deposition, and it 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 across all supplements. For calcium specifically, 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 [NIH ODS]. Some research also suggests that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. Importantly, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS].
Our recommendation
Our recommendation: do not take this supplement without first assessing your dietary calcium intake. If you take it, do not exceed the RDA without medical supervision, and take it separately from any prescription medications listed above. Monitor for symptoms like constipation or nausea, and consult your doctor before starting if you have a history of kidney stones or heart disease [NIH ODS].
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | NOW |
|---|---|
| Serving Size | |
| Contents | 90.0 Veg Capsule(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