Nature's Bounty Maximum Strength Melatonin 10 mg

Our assessment

The evidence shows that while calcium is a critical mineral for your body, the specific product you asked about — Nature's Bounty Maximum Strength Melatonin 10 mg — is a melatonin supplement, not a calcium supplement. Data for this melatonin product is limited, so our analysis focuses on the ingredient calcium, which is commonly taken alongside or confused with other supplements. Our assessment: calcium supplements can be effective for bone health, but the data on high intakes does not support unsupervised use of high doses [NIH ODS].

How it works

Think of calcium as a builder and a messenger in your body. It supports bone mineralization — meaning it helps deposit minerals into your bone structure to keep your skeleton strong. It also helps your muscles relax and your nerves send signals properly through neuromuscular relaxation [NIH ODS]. Without enough calcium, your body will pull it from your bones, which can weaken them over time.

Safety profile

The FDA received a total of 592,059 adverse event reports across all supplement categories, though specific numbers for this product are not available. For calcium specifically, high intakes carry real risks. Some research suggests that high calcium intakes might increase the risk of heart disease and prostate cancer [NIH ODS]. Very high levels of calcium 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]. Data on side effects for the melatonin product itself is not available.

Our recommendation

If you are taking calcium for bone health, do not exceed the recommended dietary allowance without a doctor's guidance. Calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS]. Take calcium supplements separately from these medications by at least two hours. For the Nature's Bounty Melatonin 10 mg product, data is not available to form a specific recommendation — speak with your pharmacist about whether this dose is appropriate for you.

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