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Magnesium Glycinate vs Magnesium L-Threonate
Magnesium glycinate vs L-threonate is a choice between two forms of the same mineral. Both are sold for the brain, yet it is not known whether either improves thinking. Synaptril uses glycinate, 80 mg of magnesium per capsule. The threonate trials were small and used a different product.
Written by the Synaptril label deskUpdated · 4 min read
What is the difference between magnesium glycinate and L-threonate?
They are the same mineral bound to different partners: glycine in one, threonate in the other.
The pairing matters for dose math. Magnesium glycinate is about 14% magnesium by weight (GlobalRPH, Magnesium Glycinate). Labels list elemental magnesium, not compound weight (NIH ODS, Magnesium).
Which form has better brain evidence?
Neither has a settled case. The ADDF review says it is not known whether magnesium improves cognition or prevents dementia (ADDF Cognitive Vitality, Magnesium).
It found only three double-blind trials, two at high risk of bias. The one low-risk trial used glycinate for 12 weeks and showed a 9.1% score gain only in people over 65, with no benefit in younger participants. L-threonate trials were small: 44 people, and 109 people on a multi-ingredient product (ADDF Cognitive Vitality, Magnesium).
| Form | Trial detail |
|---|---|
| Glycinate | 12 weeks; gain only over age 65 |
| L-threonate | 44 people; 109 on a combination |
Which magnesium form does Synaptril use?
Synaptril uses magnesium glycinate, printed as 80 mg of magnesium (19% DV). It is the first and largest line of the 575 mg blend.
That works out to about 567 mg of glycinate for 80 mg of magnesium, nearly the whole blend. The label does not mention L-threonate. Magnesium has only low-certainty sleep evidence (Mah & Pitre, BMC Complement Med Ther 2021).
- 1Magnesium Glycinate (magnesium 80 mg, 19% DV)Line 1 · 80 mg magnesium (19% DV)
- 2Alpha Lipoic AcidLine 2 · at most 175 mg per capsule
- 3Butcher's Broom (Ruscus aculeatus) Root ExtractLine 3 · at most 88 mg per capsule
- 4L-CarnitineLine 4 · at most 58 mg per capsule
- 5Turmeric (Curcuma longa) Rhizome Extract 95% CurcuminoidsLine 5 · at most 44 mg per capsule
- 6Coenzyme Q 10 (as Ubiquinone)Line 6 · at most 35 mg per capsule
From the Supplement Facts panel. The six lines are the 575 mg blend, listed from most to least by weight (21 CFR 101.36, Supplement Facts). Other ingredients (the vegetable capsule, cellulose, magnesium stearate, stearic acid, silicon dioxide) are not counted.
Synaptril: from $49 a bottle30 capsules · 2, 3 or 6 bottles · free shipping on 3 or 6 · 60-day guarantee
See packsHow should you choose between the two forms?
Choose by the label amount, your stomach and your medicines, not by the brain claim. Neither form has earned it.
Check the amount first, because a bigger compound weight does not mean more magnesium.
We found no verified price comparison of the two forms, so we make none. Magnesium can bind antibiotics and osteoporosis drugs (NIH ODS, Magnesium). Keep taking prescribed medicine. See magnesium glycinate, compare and pricing.
Order Synaptril on the official checkout
Order-page prices, October 18, 2026 (Synaptril sales page). The 2-bottle pack is $178 plus shipping. Every pack has the 60-day money-back guarantee. Compare all packs.
FAQ01
Synaptril questions people ask
Is magnesium L-threonate better than glycinate for memory?
That is not shown. The ADDF review found small L-threonate trials and a glycinate trial that helped only people over 65. No head-to-head result exists in those findings.
Does Synaptril contain magnesium L-threonate?
No. The label lists magnesium glycinate, not L-threonate. Its printed amount is 80 mg of magnesium per capsule.
Can magnesium glycinate cause side effects?
High supplemental doses commonly cause diarrhea, nausea and cramping. Synaptril's 80 mg is well below the 350 mg upper limit from supplements.
Who wrote this02
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Pages built from the label, the sales page and linked NIH, FDA, CDC, FTC and peer-reviewed sources.
Last updated . Learn about our editorial standards and how we check reviews. This website is run by a U.S. retail partner of Synaptril, not by the manufacturer or the distributor. We make money when you buy through our order links.
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