

🧠 Elevate your mind, rest your body, own your day.
Sports Research Magnesium L-Threonate Capsules deliver 2000mg of highly bioavailable Magtein®, a patented form of magnesium proven to cross the blood-brain barrier. Designed to enhance brain health, memory, focus, and promote restful sleep, this vegan, non-GMO, and gluten-free supplement is manufactured in the USA under strict quality standards. With 90 capsules per bottle, it offers a convenient one-month supply to support cognitive function and overall wellness.


















| ASIN | B0B336FCWC |
| Best Sellers Rank | #1,632 in Health & Household ( See Top 100 in Health & Household ) #37 in Magnesium Mineral Supplements |
| Customer Reviews | 4.7 4.7 out of 5 stars (1,883) |
| Date First Available | January 1, 2022 |
| Item model number | FG377 |
| Manufacturer | Sports Research |
| Product Dimensions | 2.45 x 2.45 x 4.5 inches; 0.07 ounces |
N**R
Life-Changing Magnesium — Better Sleep & Better Mood!
I’ve been taking these Sports Research Magnesium L-Threonate capsules for about 4 months now, and they are honestly amazing. I originally bought them to help with sleep, and they’ve made a huge difference — I fall asleep easier, stay asleep longer, and wake up feeling more rested instead of groggy. What I didn’t expect was how much they would also improve my mood. Since taking these consistently, I feel calmer, more balanced, and less stressed throughout the day. It really feels like my brain and body just function better on this form of magnesium. This formula absorbs well, doesn’t upset my stomach, and the capsules are easy to take. I’ve tried other types of magnesium, but none of them have worked nearly as well as Magtein. If you’re looking for something to support sleep, focus, or mood, I highly recommend giving these a try. They’ve made a noticeable difference for me, and I’ll definitely keep taking them!
Q**Y
Working Well for Better Sleep
Been combining a serving of this with 200 mg L-theanine an hour before bed and I've been sleeping much better since starting this combination. Seems to be a good product, and works well for me. I would say I typically have insomnia 1-2 days per week, and I haven't had any issues with it since starting this and L-theanine.
B**N
Great quality.
Great brand, high quality. Helps with sleep!
L**J
Good quality supplement
I like the quality and research behind this brand. This supplement is good quality and potent when taken at the recommended dose.
T**A
will calm your racing mind, subtle relaxation, and eventually helps you fall asleep
I have always been taking mag glycinate as my go-to for muscle recovery and relaxation. but recently heard how this one relaxes the mind/brain so I decided to give this a try for the first time and I totally love it. when I am still jittery from the coffee I had earlier in the day, taking this at night is a game changer. it instantly calms my anxious thoughts and centers me. it also helps me sleep. i always pop a mag for sleep. its the best, no drowsy feeling the next day ONLY IF you don't take it in the middle of the night. and although the dose says 3 capsules, I think 2 works just fine for me.
M**K
Magnesium without the laxative effect.
Overall I'd say it's good, but it doesn't make me sleepy or tired. It feels like my sleep is lighter, and according to my Fitbit my sleep quality is lower when I take this right before bed. But maybe I need to take more than a single dose? 🤷 Really if your goal is to restore your magnesium stores this seems like a good supplement with few drawbacks. No laxative side effects. Seems to reduce muscle tension caused by vit d supplementation. The main downside is the capsules are huge and a single dose is 3x of them. It makes me feel like I'm taking a lot. In terms of sleep, I had better luck with my magnesium citramate from Thorne. But it had the laxative effect.
A**R
Cuts RLS 75%
I have restless leg syndrome and leg cramps at night. My neurologist suggested these because the body absorbs the magnesium more than just what you can buy at Walmart. This is really helped reduce the occurrences and reduces the pain
J**B
Knocks me out fast — just don’t mix with wine
This magnesium L-threonate works extremely well for me. Within about 20 minutes of taking it, I feel super relaxed and sleepy, and I sleep incredibly well through the night. It’s one of the best sleep supplements I’ve tried. One thing I did notice is that if I have wine or alcohol the same evening, my sleep becomes much lighter and not nearly as restful, even when I take this. On nights without alcohol, the sleep quality is deep and very refreshing. The capsules are easy to swallow. It says take 3 but I take 2. If you’re looking for something to help you fall asleep quickly and get truly restful sleep, this has been excellent!
M**M
Sports Research is a great brand for Magtein Magnesium L-Threonate. I always take this brand and it works well. I am pleased with the results. I would recommend and I would purchase again.
R**Y
Very relaxing and calmed the anxiety that came with peri-menopause, I use the Magnesium Glycinate and the L-Threonate together at bedtime and it’s made a huge difference in mood and sleep!! I love that Sports Research is such a clean brand!!!
E**H
Magtein at the best price and it works well. Love the flip top bottle. Just an all around great staple supplement and brand.
C**.
The capsules are so large that I almost choke every other time I take them. It’s really unpleasant and uncomfortable. The brand is beautiful and the product itself is good, but I won’t repurchase simply because the capsules are gigantically oversized. I’ll be looking for an alternative next time.
M**1
Better than bisglycinate in my opinion
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