Page 1 - Reviews - Source Naturals, L-Tryptophan, 120 Tablets - iHerb

Customer Ratings & Reviews

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4.5
Based on 2,788 ratings
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English (UK)
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2155
Gold
Posted on 7/07/2026
Japan
431
1
3
360
In the morning
Verified Purchase
Actually, tryptophan, when taken in the morning, becomes a building block for serotonin during the day and leads to melatonin production at night, so some believe that taking it in the morning is recommended for regulating sleep rhythms! If your goal is sleep, it's similar to taking half a tablet of about 155mg, so it's probably best to start by trying 1/3 to 1/2 a tablet (about 166-250mg) 30-60 minutes before bedtime. It may be absorbed more easily on an empty stomach or after a light meal.
Auto-translated from Japanese
iHerbtomnatural
Silver
Posted on 5/01/2026
Thailand
128
0
1
22
Good product
Verified Purchase
To be honest I didn’t mean to buy these tablets, I wanted capsules for their purity. Saying that I’ve been happy with the quality, size, and the ingredients haven’t caused any side effects. I’m not sure if the benefits, they are mild but lean towards feeling relaxed and calm.
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iHerbCustomer
Silver
Posted on 14/04/2026
Kazakhstan
132
0
1
23
Great
Verified Purchase
It's a very good product, effective, the only thing is that the tablets are big and hard to swallow, but it helps, I take it
Auto-translated from Russian
iHerbCustomer
Gold
Posted on 29/03/2026
Ukraine
690
0
1
47
I advise everyone to buy dietary supplements 🌱 at the SFS store in Odessa ⚓️ I advise everyone to buy dietary supplements 🌱 at the SFS store in Odessa ⚓️
Verified Purchase
I advise everyone to buy dietary supplements 🌱 at the SFS store in Odessa ⚓️ I advise everyone to buy dietary supplements 🌱 at the SFS store in Odessa ⚓️
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patra
Silver
Posted on 30/01/2026
Japan
165
0
0
33
If you take too much, you will feel sleepy
Verified Purchase
I think one pill is enough to have an effect. If I take it in the morning, I get sleepy, so I take it before going to bed at night. It makes me feel calmer.
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patra
Silver
Posted on 30/01/2026
Japan
165
0
0
33
If you take too much, you will feel sleepy
Verified Purchase
I read a review saying to take it in the morning, so I took two tablets and went to work, but I felt unusually sleepy. I guess I need to adjust the dosage.
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iHerb Customer
Silver
Posted on 14/01/2026
South Korea
103
0
0
2
I take tryptophan before going to bed to manage my condition.
Verified Purchase
I take tryptophan before bed to manage my condition. The capsules are small, making them easy to swallow, and the absence of any noticeable odor makes them easy to consume. After taking them for a while, I've noticed a slight improvement in my nighttime well-being. The clean ingredients, free of unnecessary additives, mean I can continue to take them with confidence. The overall quality has also been stable.
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choi
Gold
Posted on 28/11/2025
South Korea
392
0
0
33
I started taking tryptophan supplements because I had a lot of trouble sleeping and tossing and turning.
Verified Purchase
I started taking a tryptophan supplement because I often toss and turn due to my sensitive sleep. This product is made from pure amino acids, so it's easy to take with other supplements, and the small capsules make it easy to swallow with a sip of water before bed. After taking it consistently for about three weeks, I noticed a noticeable improvement in my ability to fall asleep faster and wake up less frequently during the night. The quality is also consistent, so I can take it every day without any discomfort, and I feel noticeably more refreshed when I wake up in the morning. I highly recommend this product to anyone experiencing poor sleep quality.
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iHerbCustomer
Gold
Posted on 27/11/2025
Japan
347
0
0
43
Verified Purchase
The main effects of tryptophan are mental stability, improved sleep quality, and stress reduction. These are due to tryptophan being a precursor to serotonin, known as the "happiness hormone," and melatonin, the "sleep hormone" that promotes sleep. A deficiency of tryptophan can lead to insomnia and depression, so it's important to actively consume it.
Auto-translated from Japanese
iHerb Customer
Gold
Posted on 30/10/2025
Kazakhstan
505
0
0
2
Verified Purchase
I've been taking this supplement for about a month now and am very pleased with the results! I feel noticeably better—I have more energy, my fatigue has gone away, and my sleep and mood have improved. I'm especially pleased that the effects are gentle and without any side effects. The ingredients are natural, without any unnecessary chemicals, which is very important to me.
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