NOW Probiotic Defense
Brand: NOW · Form: CAPSULE [E0159]
Our assessment
The evidence shows that this product is a probiotic supplement, and its primary ingredient, calcium, has well-documented benefits for bone health. Our assessment: if you are looking to support bone density and muscle function, calcium is a key mineral, but you should be aware of the risks and interactions associated with high intake [NIH ODS].
How it works
Think of calcium as a structural building block for your bones. It supports bone mineralization and density, and it also plays a role in neuromuscular relaxation and nerve signaling [NIH ODS]. This means it helps your muscles relax after contracting and supports proper nerve function.
Safety profile
Data on side effects for this specific product is not available. However, the FDA has received 592,059 adverse event reports total for all dietary supplements. For calcium specifically, high intakes might increase the risk of heart disease and prostate cancer. 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].
Our recommendation
We recommend you speak with your healthcare provider before starting this supplement, especially if you take medications. Calcium can reduce the absorption of bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS]. For most adults, it is best to get calcium from food first, and use supplements only to fill a gap confirmed by a doctor.
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