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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 11-20 of 69 reviews
May 26, 2026
Reviewer name: SarahH
5 out of 5 stars
5 out of 5 stars review

Calming, great ingredients

I'm really enjoying this supplement! There is a simple ingredient list and they are beneficial in supporting restful sleep and calming. This is meant to be relaxing and calming, it's not a sedative. Don't expect to be knocked out cold! But I definitely find this calming, kinda like how some people have their chamomile tea or lavender spray. This is along those lines of support in my opinion. It mixed into water great, no clumps. Tastes pleasant. No artificial flavors or colors either. I will continue using this, even during the daytime when I am feeling frazzled. I love that it has 200mg l-theanine as well, and several different forms of magnesium.

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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 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 23, 2026
Reviewer name: RubenG
4 out of 5 stars
4 out of 5 stars review

Great supplement, no pills

The magnesium powder does the job. When you thoroughly mix the powder in with the water the texture is very smooth. Definitely better than taking pills at night. Been taking it for a few weeks, and it's been working great. The jar makes a lot portions. Only downside is, that its very sweet, so I need to dilute it with more water.

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May 29, 2026
Reviewer name: ShinesS
5 out of 5 stars
5 out of 5 stars review

Member's Mark Magnesium powder dietary supplement

I've been using this magnesium powder for a few weeks now, and overall I think it works really well. The biggest downside for me is definitely the taste — the cherry flavor is pretty tart and a little stronger than I expected. It's not terrible, but if you're sensitive to sour flavors you may not love drinking it plain with water. I found it tastes a bit better with extra cold water or ice. That being said, the results have been worth it for me. I've noticed that I feel calmer and more relaxed before bed, and my sleep quality has improved a bit since taking it consistently. I also like that it comes in powder form because it's much easier than swallowing large magnesium pills. Also the container has enough quantity with a scoop as well. Another small negative is that it doesn't dissolve perfectly every single time, so you have to mix it well. But for the price and the benefits, I still think it's a great value. If you can get past the tart flavor, it's definitely worth trying for relaxation and sleep support. This product was sent to me by Influenster for my honest review.

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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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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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Aug 5, 2026
Reviewer name: VirginiaB
1 out of 5 stars
1 out of 5 stars review

Not for me

Not for me took them for 4 days really seen no difference i know supplements take awhile until you notice a difference but I kept forgetting to use it

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Jul 23, 2026
Reviewer name: SandyP
5 out of 5 stars
5 out of 5 stars review

Great supplement for your night routine

The supplemental can be added to your daily routine and easily dissolves. You can mix it either water and it has a pleasant taste. All you need is one scoop, which is included in the container. It relaxes you and allows you to sleep right away.

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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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