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HealthVetted
Head-to-head · 2026

NOW Foods L-Theanine Double Strength 200 mgvsNatrol Advanced Sleep Melatonin 10 mg (Time Release)

Top pick

NOW Foods L-Theanine Double Strength 200 mg

L-Theanine

Score7.8/10

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

Melatonin

Score7.7/10
Updated

Side-by-side

#ProductStarting priceScoreActions
1NOW Foods L-Theanine Double Strength 200 mg$19/moTop ·7.8See offer →
2Natrol Advanced Sleep Melatonin 10 mg (Time Release)Best ·$8/mo7.7See offer →
Score comparison

Side-by-side scoring breakdown

NOW Foods L-Theanine Double Strength 200 mgNatrol Advanced Sleep Melatonin 10 mg (Time Release)
Effectiveness
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
6.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
6.0
Safety
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
9.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
7.0
Value
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
8.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
9.0
Accessibility
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
9.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
10.0
User experience
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
8.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
7.0
Trust
0 — 10
NOW Foods L-Theanine Double Strength 200 mg
7.0
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
7.0

How they work

NOW Foods L-Theanine Double Strength 200 mg

L-theanine is an amino acid found almost exclusively in tea leaves. It readily crosses the blood-brain barrier and increases alpha-wave activity, the brain pattern associated with relaxed wakefulness, while modulating the neurotransmitters GABA, serotonin, and dopamine. The result is a relaxed but clear-headed state that can lower the physiological and mental arousal that blocks sleep onset, which is why it is studied for both stress and sleep quality rather than as a sedative.

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

Melatonin is the hormone your pineal gland releases as darkness falls to tell the brain it is time to sleep. Supplementing it binds the same MT1 and MT2 receptors, which can advance or initiate the sleep phase. Natrol's two-layer tablet releases part of the dose quickly to help with sleep onset and the rest gradually to support staying asleep, and adds vitamin B6, a cofactor in the body's own melatonin synthesis.

Effectiveness

NOW Foods L-Theanine Double Strength 200 mg

A 2019 randomized, placebo-controlled crossover trial found that 200 mg/day of L-theanine for four weeks reduced anxiety and depression scores and improved Pittsburgh Sleep Quality Index subscales for sleep latency, sleep disturbance, and use of sleep medication in healthy adults. A 2025 systematic review of supplementation trials concluded L-theanine can improve some subjective sleep outcomes, and combination studies (for example with a milk-protein hydrolysate) have shown reduced sleep disturbance. Overall the effect is modest and primarily mediated through reduced stress and arousal rather than direct sedation.

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

Melatonin's evidence is strongest for circadian problems such as jet lag and delayed sleep phase, where it can meaningfully shift sleep timing. For falling asleep faster in general, meta-analyses show a real but small benefit, often cutting sleep latency by only several minutes. The AASM gives melatonin a weak recommendation against use for chronic insomnia, citing limited efficacy and safety data. Higher doses like 10 mg are not proven more effective than lower ones and raise the chance of side effects.

Side effects

NOW Foods L-Theanine Double Strength 200 mg

L-theanine is among the best-tolerated supplements in this category, with side effects being uncommon and mild, such as occasional headache or stomach upset. Because it promotes relaxation, combining it with alcohol or sedative medications could be additive, so use judgment. This is educational information, not medical advice; individual results vary.

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

The most common complaints are next-morning grogginess, headache, and vivid dreams, all more likely at this 10 mg strength. Melatonin can interact with several medication classes. Because supplemental melatonin is not tightly regulated, independent testing has found products whose actual content differs from the label, so brand reputation matters. This is educational information, not medical advice; individual results vary.

Cost & value

NOW Foods L-Theanine Double Strength 200 mg

Roughly $18-$24 for 120 capsules as of 2026, frequently discounted under $20, with a larger 180-count value size available. At one capsule daily that is months of supply for the price of a few coffees, and the product is often HSA/FSA eligible. Note the formula includes 100 mg of inositol, so it is not a single-ingredient product.

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

At roughly $8-$12 for 60 tablets as of 2026, this is one of the lowest cost-per-night sleep aids on the market - typically well under 20 cents a dose. It is widely HSA/FSA eligible. The real cost is not money but the high dose: most users do not need 10 mg.

Who it's for

NOW Foods L-Theanine Double Strength 200 mg

Adults whose sleeplessness is tied to stress, anxiety, or an overactive mind, or who want daytime calm without sedation. People who are pregnant or nursing, who take sedatives or blood-pressure medication, or who have a diagnosed anxiety or sleep disorder should consult a clinician. It is not a substitute for treatment of clinical insomnia.

Natrol Advanced Sleep Melatonin 10 mg (Time Release)

Adults dealing with jet lag, shift-work sleep disruption, or occasional sleeplessness. Not recommended for children without pediatric guidance, for pregnant or nursing people, or for those on blood thinners, sedatives, immunosuppressants, or blood-pressure medication without checking with a clinician. Avoid driving or operating machinery until you know how it affects you.

NOW Foods L-Theanine Double Strength 200 mg
+Non-sedating calm - useful for a racing mind at bedtime
+Strong safety and tolerability record at the studied 200 mg dose
+RCT evidence for reduced stress and improved sleep-quality scores
+Inexpensive and widely available without a prescription
−Effect is anxiolytic and subtle, not a true sleep inducer
−Contains added inositol, so it is not a pure L-theanine product
−Best results in studies came from daily use, not a single occasional dose
−Not a treatment for diagnosed insomnia or an anxiety disorder
Natrol Advanced Sleep Melatonin 10 mg (Time Release)
+Extremely inexpensive and stocked nearly everywhere in the US
+Two-layer design targets both falling asleep and staying asleep
+Useful for jet lag, shift work, and resetting a delayed sleep schedule
+No prescription required and non-habit-forming
−10 mg is far higher than the ~0.5-3 mg most experts consider effective
−Not recommended by the AASM as a treatment for chronic insomnia
−Can cause next-morning grogginess, vivid dreams, or headache
−Melatonin supplements are unregulated for potency, so actual dose can vary by product

Bottom line

Natrol Advanced Sleep Melatonin 10 mg (Time Release): A cheap, ubiquitous melatonin that shines for jet lag and the occasional off night, but the 10 mg dose is overkill for most people and it is not the right tool for chronic insomnia. Both are strong options — match the pick to your specific needs, budget, and clinician's guidance.

Editorial comparison, not medical advice. Discuss options with a qualified clinician. Individual results vary.