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Customer reviews for Member's Mark L-Theanine & Tart Cherry Magnesium Sleep Powder Supplement for
Member's Mark L-Theanine & Tart Cherry Magnesium Sleep Powder Supplement
3.6 out of 5 stars
stars
27 ratings24 reviews
  1. 5 stars48% (13)
  2. 4 stars15% (4)
  3. 3 stars7% (2)
  4. 2 stars7% (2)
  5. 1 star22% (6)
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Showing 11-20 of 24 reviews
Jul 3, 2026
jeffa1234
5 out of 5 stars review

Verified Purchase

Calming

Calms me down

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Jun 28, 2026
Linda
1 out of 5 stars review

Verified Purchase

No way

Taste was way too sweet

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Jun 13, 2026
anonymous
5 out of 5 stars review

Incredible relief

It would be hard to overstate what a difference this has made for me. I feel the effects immediately, sleep better as proven by watch data, and even drink less alcohol. I’m not a person who takes supplements (or writes reviews) but I found this in a desperate search for relief and it delivers.

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Jul 13, 2026
anonymous
2 out of 5 stars review

Cough Syrup anyone?

As other reviewers have pointed out, it tasted just like cough syrup does… but I am not drinking this for taste, I am drinking it for sleep… so, I have found that tart cherry does in fact improve my sleep, which is a godsend, but this cough syrup taste, combined with the fact that you have to mix it with water and drink it, (getting up to pee in the middle of the night kinda cancels out the beneficial effect…) I will be sticking with tart cherry gummies for sure. If they made this tart cherry/L-theanine in a gummy, I would definitely try it. As a powder to down as a nightcap before bedtime, I’ll pass.

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May 31, 2026
anonymous
5 out of 5 stars review

A must have for insomniacs lol

I’ve struggled with insomnia for yrs and this has so far been the best product to help out w deep sleep. I used to get about 2-4hrs of sleep and now i’m reaching the 6-8hrs of sleep, slowly going up. It took about a week for me to see the difference.

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May 21, 2026
anonymous
5 out of 5 stars review

Very Good Product

Great product to help you rest well and feel restored upon waking up. I’m seeing complaints about taste, keep in mind this is not a margarita it is a supplement. The taste is not bad at all for this product. I would suggest this powder to anyone and hopefully Sam’s makes this a permanent item for sale.

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May 4, 2026
anonymous
3 out of 5 stars review

Better out there

This powder is very grainy/chalky and it smells/tastes like cherry medicine. I’ve tried using hot water to see if it would better mix, but that didn’t work. Stirring for over a minute straight didn’t work either. I’ve tried the recommended 6-8 oz of water, but that just prolonged drinking it, so I’ve been using as little water as I can so that I can just chug it and get it down. All that being said, I do feel like this product works. Within 30 minutes it kicks in and I feel peaceful and calmer. I’ll continue to use this jar up, but I’m definitely on the lookout for something that doesn’t have this grainy issue and the smell. I like cherry, but this is just too artificial tasting.

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Jun 4, 2026
anonymous
3 out of 5 stars review

Miss the old MM Mag

Bought to replace my beloved members mark magnesium glycinate tablets. I want those back I much prefer that form factor. This drink tastes super medicinal and is sitting hard in my stomach.

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May 27, 2026
Susanne
4 out of 5 stars review

At first, I didn't feel like this worked that well. But the more I take it, the better it works. My husband sleeps better too.

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May 31, 2026
anonymous
5 out of 5 stars review

Works great

seems to work very well. since taking this product and ashwagandah at night, I've been getting full night sleep. I have no issue with the flavor.

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