Glycine vs Melatonin: The Natural Feel vs The Drug Feel
People often say Melatonin gives them weird dreams or a "hangover." Glycine rarely does.
Glycine mimics the body's natural temperature drop that happens at night. It feels like a natural tiredness. Melatonin is a hormone signal that forces the brain into "night mode," sometimes aggressively.
| Feature | Glycine | Melatonin |
|---|---|---|
| Daily Use | Safe / Recommended | Not Recommended (Short term only) |
| Mechanism | Vasodilation / Core Cooling | Circadian Signaling |
| Morning Feel | Refreshed | Often Groggy |
| Effect on Dreams | Neutral | Vivid / Intense |
Mechanisms: Physiology vs Endocrinology
Glycine: The Cool Down
Glycine helps you sleep by physically manipulating blood flow. It moves blood to the skin, which releases heat. Biologically, you cannot fall asleep if your core body temperature is too high.
What it means
It removes a physical barrier to sleep.
Melatonin: The Master Clock
Melatonin is the "hormone of darkness." Taking it overrides your brain's internal clock. This is powerful, but if you take too much (most pills are 5mg, which is huge), receptors desensitize.
What it means
It forces the system to shut down.
Which One Matches Your Goal?
For Shift Work / Jet Lag
Winner: Melatonin.
Glycine cannot reset your circadian clock. Only Melatonin (or light exposure) can do that.
For Daily Insomnia
Winner: Glycine.
If you just want to sleep better every night without messing with your hormones, Glycine (3 grams) is the safer, more sustainable choice.
The Verdict
Choose Glycine if: You want a daily sleep improver with no side effects.
Choose Melatonin if: You need to force your body to sleep at a weird time (e.g., after a flight).