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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
3.8 out of 5 stars
stars
73 ratings69 reviews
  1. 5 stars52% (38)
  2. 4 stars18% (13)
  3. 3 stars10% (7)
  4. 2 stars4% (3)
  5. 1 star16% (12)

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Showing 1-10 of 69 reviews
May 4, 2026
Reviewer name: RaitzaB
5 out of 5 stars
5 out of 5 stars review

Good product. Works perfectly

This product works pretty well! The flavor is not my favorite because I don’t really like cherry. But it’s not that bad I like to take it at night before bed and helps me with my mood and sleep. The dissolving is amazing pretty fast. And the packaging is great taste fresh.

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May 2, 2026
Reviewer name: TaraT
5 out of 5 stars
5 out of 5 stars review

It works!

I recently got into magnesium for a calming supplement after trying it many years ago and not feeling a difference. I finally gave it a fair shot and it works great! My body chemistry may have changed with age but it works so well for me now and this particular brand I was truly impressed with how effective it was. I am so happy it doesn't contain melatonin because I am not a fan of that and the grogginess that comes with it. The taste is decent and it mixes well with liquid and come with a scoop for easy measuring.

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Jun 6, 2026
Reviewer name: MariaM
5 out of 5 stars
5 out of 5 stars review

Rest in a glass

There are many products on the market that claim to do everything that this product does and are not even close to actually doing it. This is one of the only magnesium supplements that actually does help me sleep. The L-Theanine is the star of the show and is what really helps in causing that restful sleep. The tart cherry flavor is palatable and quite refreshing. The powder dissolves quite quickly.

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May 5, 2026
Reviewer name: NicholeB
5 out of 5 stars
5 out of 5 stars review

So far so good! Nice flavor, natural ingredients �

I love the natural ingredients in this product! I don’t have a lot of experience with magnesium but my sleep does feel more restorative! The flavor is very strong (but tastes good) so either add more water or use less than a full scoop of strong flavor is not your bag. Container and scoop store well, no concerns there.

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Jun 3, 2026
Reviewer name: AlexesMarieM
5 out of 5 stars
5 out of 5 stars review

Say hello to restful nights.

What a great addition to my daily routine. The powder is easy to stir and mixes very well with your favourite drink. It has no weird texture but has an amazing cherry taste. It also comes from clean sources, what more can you ask. A must try for everyone needing a little help with sleep.

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May 30, 2026
Reviewer name: SaritaS
5 out of 5 stars
5 out of 5 stars review

Great drug free alternative

This is a great option if you have problems with falling asleep and want a melatonin free option. It’s easy to mix and dissolves easily. Has a nice fruity flavor and sometimes I’m able to mix it into my smoothie or tea in the evening. I love that it comes with its own scoop and that it’s a healthier drug free formula

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May 5, 2026
Reviewer name: SusanB
4 out of 5 stars
4 out of 5 stars review

Great magnesium source but start small

I received this magnesium sleep supplement from Members Mark free for testing and review purposes. I use a melatonin supplement for sleep and a magnesium supplement already, so I was excited to try this. Tart cherries already naturally contain melatonin. This has tart cherry extract, the amino acid L- theanine, and vitamin B6. The magnesium component has magnesium biglycinate chelate, citrate, and glycinate. Other ingredients include beet extract, malic acid, and stevia for sweetness. The container comes with a scooper, and directions say to use one scoop in 6-8 ounces of water. I recommend starting even smaller, and use at night, but not before bed. I did not find a difference in sleep, but it’s a good magnesium source. I think I reacted to the citrate form. I had to take medication to stop going to the bathroom, and I determined it’s best for me not to use this before bed. The cherry taste has a bitter aftertaste so I suggest blending it like a smoothie instead of shaking in a jar like I did.

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Jun 5, 2026
Reviewer name: AmyW
4 out of 5 stars
4 out of 5 stars review

If you’re chasing better sleep, it’s worth trying to see if this helps you.

I think it did contribute to a better nights sleep. Even more so is I didn’t have wine with dinner. The flavor is tart as advertised but doable. I only tried it with water. They said you can mix with other beverages but I haven’t tried that yet. The tub looks small, but the scoop is small. A little goes a long ways. If you’re having trouble getting a good nights sleep or looking for a more restful night sleep, it’s worth trying.

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May 26, 2026
Reviewer name: JaclynC
3 out of 5 stars
3 out of 5 stars review

Not bad but don’t prefer it

I like the idea of this and it’s pretty easy to use but I still prefer just an oral supplement instead of a drink. The taste isn’t bad but it’s not great. Very Cherry. In general magnesium helps me fall asleep and doesn’t leave me feeling groggy the next day so this is no different but it’s easier to just swallow a magnesium supplement. Drinking a cup of water before bed isn’t great on my bladder

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Jun 13, 2026
Reviewer name: MakenzieS
1 out of 5 stars
1 out of 5 stars review

Too strong of a taste

I honestly did not like this product. It did not help me sleep. It didn’t have any negative side effects, other than the horrible taste. It doesn’t dissolve well in liquid. I mixed it with almond milk and it tasted extremely strong no matter how much liquid I added, and there was still chunks of undissolved powder even after using a frother. I feel like there is just better products out there and this is just not worth it.

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