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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
3.9 out of 5 stars
stars
76 ratings70 reviews
  1. 5 stars53% (40)
  2. 4 stars18% (14)
  3. 3 stars9% (7)
  4. 2 stars4% (3)
  5. 1 star16% (12)

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Showing 1-10 of 70 reviews
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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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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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 9, 2026
Reviewer name: ScarlettH
5 out of 5 stars
5 out of 5 stars review

Convenient

This supplement has been a great addition to my routine. The powder mixes easily into water and has a light, pleasant taste. I’ve noticed it’s helped me feel more relaxed in the evenings and helped support muscle recovery after workouts. The 11 1/2 ounce container lasts a long time, making it a good value for the price. I also appreciate that it’s easy on the stomach compared to some magnesium capsules I’ve taken before. Overall, this is a convenient effective supplant and I would highly recommend it.

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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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May 7, 2026
Reviewer name: GreysonS
4 out of 5 stars
4 out of 5 stars review

Tastes great, mixes well, and feels easy to add to

I’ve been trying the Member’s Mark Magnesium Powder with L-Theanine & Tart Cherry for a few nights now. The flavor is really pleasant, and it mixes into water smoothly. I also appreciate that it doesn’t leave me feeling tired or groggy the next morning, which has happened with other sleep aid products. I haven’t noticed a dramatic change in my sleep yet, but I plan to keep using it to see if the effects build over time. Overall, it’s easy to take and enjoyable, and it feels like a nice addition to my nighttime routine. Nice storage container and well packaged.

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Apr 26, 2026
Reviewer name: KimW
4 out of 5 stars
4 out of 5 stars review

Works well, tastes gross

Mixes in water easily, and dissolves well. It will last a long time, according to the expiration date on the bottom! It seems to work really well, but ma the taste and smell are awful.. it tastes like cherry cough syrup. I choked it down, and I slept great but it will likely not become a nightly routine for me, unfortunately

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Apr 19, 2026
Reviewer name: TessB
3 out of 5 stars
3 out of 5 stars review

Not my favorite flavor

One scoop definitely gives you a strong drink. I don’t love the flavor; sort of tastes like medicine. Wondering if adding more water would make it better so it’s less strong. Definitely settles at the bottom so you have to stir it multiple times (never fully dissolved). We’ll see how effective it is.

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Sep 6, 2026
Reviewer name: Lucia
1 out of 5 stars
1 out of 5 stars review

Verified Purchase

Tastes horrible, ineffective,

This product tastes horrible, wears out in about 4 hours. It's also inconvenient as it needs to be dissolved in 6 -8 ounces of fluids, makes me wake up in the night to go pee and afterwards it's already out of your system and doesn't help with sleep anymore. Will not be buying again. I was previously using the members mark magnesium pill with L theanine and was getting the best restful sleep that I never knew I could achieve but Sam's Club stopped carrying it with no warning or reason.Please return the previous members mark magnesium pill with l theanine. This is a terrible substitute. Ewww

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Jul 18, 2026
Reviewer name: anonymous
1 out of 5 stars
1 out of 5 stars review

Blowouts incoming!

Although I don’t mind the flavor as other reviewers have expressed their distaste, it gives my digestive system fits. If I drink this before bed, I wake up in the night racing out of bed and to the bathroom. TMI I know.

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