21st Century Melatonin 3 mg
Brand: 21st Century · Form: TABLET [E0155]
Our assessment
The evidence shows that melatonin is a popular supplement for sleep support, but the specific product you asked about — 21st Century Melatonin 3 mg — contains calcium as a listed ingredient. Our assessment is that calcium is primarily known for its role in bone health, not sleep. The data for calcium as a sleep aid is not available. You should be aware that the FDA has received a total of 592,059 adverse event reports for all supplements, though this number is not specific to this product [FDA data].
How it works
Think of calcium as a structural building block for your bones. It supports bone mineralization and density, and also plays a role in neuromuscular relaxation and nerve signaling [NIH ODS]. While this might sound helpful for relaxation, the data does not connect calcium directly to initiating or maintaining sleep. For melatonin's specific mechanism of action, data is not available in the provided information.
Safety profile
High levels of calcium 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]. Additionally, calcium can reduce the absorption of several medications, including bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS]. Data on side effects specific to this 3 mg melatonin product is not available.
Our recommendation
Given the data provided, we cannot recommend 21st Century Melatonin 3 mg for sleep support based on the calcium content alone. The calcium dose is not specified on the label data we have, which is a critical missing piece. If you are considering this product for sleep, you should look for a supplement with melatonin as the primary active ingredient, and be aware that calcium supplements may interact with important medications [NIH ODS]. Always consult your pharmacist or doctor before starting a new supplement regimen.
AI-assisted analysis. Data sourced from NIH DSLD.
Supplement Facts
| Brand | 21st Century |
|---|---|
| Serving Size | |
| Contents | 90.0 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