Natural Factors Stress-Relax Melatonin 10 mg

Our assessment

The evidence shows that this product contains 10 mg of melatonin, a dose that is significantly higher than the typical 0.5 mg to 5 mg range commonly used for sleep support. While melatonin is a popular supplement, the data for high doses like this is limited, and we advise caution. The primary ingredient is melatonin, but the label is incomplete, so we cannot verify all components.

How it works

Melatonin is a hormone your body naturally produces to regulate your sleep-wake cycle. It works by signaling to your brain that it is time to sleep, helping to reduce the time it takes to fall asleep. At a 10 mg dose, you may experience a strong sedative effect, but this is not necessarily more effective than lower doses for most people [NIH ODS].

Safety profile

Data not available for this specific product. However, the FDA has received a total of 592,059 adverse event reports across all dietary supplements. For melatonin specifically, common side effects can include drowsiness, headache, dizziness, and nausea. Because this is a high dose (10 mg), you may be more likely to experience next-day grogginess or vivid dreams. Do not drive or operate machinery after taking it [FDA data].

Our recommendation

We recommend starting with a much lower dose, such as 0.5 mg to 3 mg, taken 30 to 60 minutes before bed. The 10 mg dose is best reserved for specific cases under a doctor's guidance, such as for shift work disorder or jet lag. If you choose to use this product, do not take it nightly for extended periods without consulting a healthcare provider. Data on long-term safety for high-dose melatonin is not available.

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