Illustration, not a product photo.
Magnesium bound to L-threonic acid, sold under the Magtein ingredient name.
104 owner comments (50 with a clear rating) from r/Supplements, r/sleep, r/insomnia, r/Nootropics, r/Adaptogens, r/Anxiety, May 2026 to October 2026. Top 95% of the 20 rated supplements.
Value for money: Not rated. The example products differ too much in dose to compare cost fairly. How we score.
Magnesium L-threonate (Magtein) is rated below most supplements we track: 3.4/5. Of 50 rated owner comments, 34 were positive, 4 mixed and 12 negative; 12 mention an unwanted effect. People talk most about side effects and deeper sleep.
Reddit comments are self-reported and unverified. They tell you what people noticed, not whether a supplement works or is safe for you.
Read how magnesium forms compare for sleep. Compare the top-rated options for grogginess by sleep problem. Compare the top-rated options for racing thoughts by sleep problem.
Supplements can interact with medicines. Talk to a doctor or pharmacist first, especially if you are pregnant, take prescription medicine (including sleep, anxiety or antidepressant medicines), or have ongoing sleep problems. See sleep supplement safety and interactions.
| Context | Rated owner comments | Positive | Negative | Unwanted effects |
|---|---|---|---|---|
| Morning grogginess | 5 | 2 | 2 | 3 |
| Deep sleep | 5 | 5 | 0 | 1 |
| Falling asleep | 3 | 3 | 0 | 0 |
| Anxiety at night | 3 | 2 | 1 | 1 |
4/5 Morning grogginessDeeper sleep“Threonate helped with pre-sleep anxiety, i usually get very anxious when i lay down cause i know if i dont get a good nights sleep i'll feel like shit the next day.”
4/5“Same here, so I tried Magnesium L-Threonate (Magtein) which works much better for me.”
4/5“The only thing that worked for me was magnesium l-threonate and ironically enough eating ice cream 2-3 hours before bed”
2/5 Emotional bluntingMood“I take 2400 mg fish oil for depression and panic attacks (been taking for 15 years), magtein before bed for anhedonia and sleep (been taking for 6 years), koji fermented iron (magceutics brand, been taking for 6 months) in the morning for…”
2/5 Fast-actingSide effects“Magnesium Threonate worked almost instantly for me, it took away the headache and overall bad feeling I get when sleep deprived.”
4/5 Deeper sleepFalling asleep faster“I take the mag threonate because mag glycinate before sleep makes me very anxious and then I can't fall asleep or stay in a deep sleep.”
4/5 Side effectsVivid dreams“Magnesium L-threonate gave me really good sleep.”
5/5“Magnesium L-threonate has been borderline life changing for me.”
4/5 Calming“I take Magnesium triple blend: Glycinate, Citrate & L-threonate.”
3/5 Morning grogginess“I just switched from mag glycinate bc it never helped me with sleep, to mag threonate and now I'm sleeping great but next day tired!”
3/5“Threonate didn't do much of anything for me, but I take mag malate now and it's been great for sleep.”
5/5“The best thing that has helped for me after everything is taking magnesium l-threonate, l-theanine, and extended release melatonin together.”
3/5“Honestly my routine got better but nothing really improved my sleep until I started taking magnesium l-threonate and melatonin 300mcg 6-hour timed release both from life extension.”
4/5 Side effects“I use magnesium glycinate & malate at night and magnesium L-threonate during the day as it helps with memory and brain fog.”
2/5“Magtein also gives me insomnia.”
4/5“Yeah I do take Malate in the morning and Threonate hour before sleep.”
4/5 Falling asleep faster“I think this is why I do better with a combo not straight L-threonate by itself.”
4/5 Side effectsVivid dreams“I like magnesium threonate. Gives me very vivid dreams but never nightmares and it's really improved my sleep.”
1/5 Morning grogginessSide effects“FWIW I've taken Now magtein for 10 years and almost every time I've tried another brand I've had horrible racing heartbeat the next day.”
5/5 Taste & form“I also drink mag T up to an hour before sleep, been getting the best sleep of my life.”
4/5“magnesium glycinate before bed is the move for sleep, the threonate is more for focus/cognition so morning or midday works better for that one, and having two different mag forms isn't redundant they do different things so that stack actually makes sense”
4/5“What worked for me was a magnesium L-Threonate, apigenin, and L-Theanine, and I decided to give my go at peptides.”
4/5“I've been using the bisglycinate for almost a year and now I've added threonate in the last month or so and it seems to be working even better.”
4/5 Cost“For me, the threonate really is worth the money and I highly recommend it, the melatonin is more likely to work for you though so if you only want to try one thing try that one.”
4/5 Takes time“Creatine and magnesium threonate helped me pull out of a similar fog, nothing miraculous but noticeable after a few weeks.”
4/5“I was in similar situations so I switched to magnesium l-threonate.”
4/5“Personally threonate works better for me for sleep…”
2/5“I've taken Thorne Glycinate and Momentous Threonate.”
3/5“Yep for me Threonate does not help me sleep.”
4/5 CostTaste & form“you might have an answer to a question i have - i take ethical nutrients mega mag at night and a magnesium threonate capsule in the morning, the evening stuff i think definitely helps but honestly i think the morning stuff is just overly…”
1/5 Side effects“Magnesium l-threonate and magnesium taurate I tolerate just fine, but magnesium bisglycinate gave me the WORST headache for some reason, and mag malate gave my insomnia (though I'm still experimenting w how I can use the mag malate to my…”
4/5“I take 1x glycinate and 1x threonate before bed.”
4/5 Deeper sleep“Ever since I started taking threonate after lunch I pop back at my desk refreshed and focused for several more hours.”
4/5“Glycinate causes insomnia for me and when I take others I'm sure they might help in the background but threonate has me waking up better than I ever have.”
4/5 CalmingFalling asleep faster“Threonate should only be taken at night.”
These are examples of Magnesium L-threonate (Magtein) products sold on Amazon. They are not ranked by Reddit and the score above is for the ingredient, not a specific product. Check the label for dose and other ingredients.
Published studies (we list them so you can read the evidence yourself; inclusion is not an endorsement):
Across 104 Reddit comments from people who say they have used it for sleep, 34 of 50 rated comments were positive and 12 negative, for a SnoozeVerdict score of 3.4/5. These are self-reported experiences, not clinical evidence.
12 of 50 rated owner comments (24%) describe an unwanted effect such as grogginess, headaches, vivid dreams or an upset stomach. Check the safety notes on this page and ask a doctor or pharmacist before starting.
Most rated owner comments come from people who talk about waking up groggy (5 comments, 2 positive).
No. The score summarizes Reddit owner comments only. Factual statements on this page link to NIH or PubMed sources, and nothing here is medical advice.
“Magnesium -- I started taking it for the muscle cramps after long runs and it turned out to help with general sleep quality too, which I wasn't expecting.”
What owners report →
“magnesium glycinate before sleep make huge difference for me, i can't go without now”
What owners report →
“I had the same reaction to mag glycinate, but mag acetyl-taurate has been life changing for me when it comes to sleep.”
What owners report →Comparisons: Magnesium glycinate vs Magnesium L-threonate (Magtein)
Last updated 2026-11-04. Mentions scanned: 334 in 264 threads.