10 Best Magnesium L Threonate

Magnesium L-threonate: what to look for

A research-relevant product should also be compared with the human evidence without treating ingredient research as proof for every finished product. Supplied studies used either 1,000 mg or 2,000 mg of Magtein magnesium L-threonate daily, including a 21-day sleep study and a six-week randomized trial in adults aged 18 to 45 who reported dissatisfied sleep. The six-week study found improvements in some cognitive and self-reported sleep-related measures, but objective sleep outcomes were not consistently better than placebo. A product containing 1,000 mg of L-threonate, or a blend that does not disclose its L-threonate amount, should not be presented as equivalent to a product providing the studied 2,000 mg amount.

Formula simplicity matters because added ingredients change the safety and evidence picture. Melatonin, valerian, chamomile, apigenin, L-theanine, vitamins, and other botanicals should be individually identified and dosed. “Brain” or “sleep” blends with undisclosed amounts make it harder to assess sedative stacking, medicine interactions, or whether the finished formula resembles a human study. Claims about uniquely crossing the blood-brain barrier, raising brain magnesium, treating memory problems, or being “clinically proven” go beyond what the supplied short-term human evidence establishes.

Quality claims also vary in strength. A current exact-product listing in a recognized independent registry is more meaningful than a brand-wide or facility-level claim. The supplied reviews used ConsumerLab, NSF dietary-supplement listings, and other certification registries to distinguish finished-product certification from a manufacturer’s GMP facility certification. A current lot-matched certificate of analysis is stronger than an uncheckable “third-party tested” statement: it should identify the lot, laboratory, methods or scope, and results for identity or potency, heavy metals, and microbiological quality. A posted testing table can still be useful, but it may not match the bottle received or disclose enough detail to verify the limits.

Packaging evidence is limited across this category. Conventional plastic bottles were common, while product-specific information about resin type, recycled content, recyclability, refills, or lower-waste design was generally absent. Buyers should therefore treat vague “eco” language cautiously and look for specific, substantiated material and disposal information rather than assuming that vegan, non-GMO, or BPA-free claims describe environmental performance.

Safety deserves attention before choosing any product. Repeated warnings across the supplied reviews include possible diarrhea, nausea, cramping, and the need to count magnesium from supplements, antacids, and laxatives. People with impaired kidney function or kidney failure should seek medical guidance because magnesium can accumulate. Several products lacked practical timing instructions for tetracycline or quinolone antibiotics and oral bisphosphonates; a pharmacist or clinician should advise on spacing and total intake. Pregnancy, breastfeeding, childhood use, multiple medicines, sedatives, or a diagnosed sleep, cognitive, neurological, or gastrointestinal condition also warrant individualized professional advice. One powder supplied 400 mg per full serving above the stated adult supplemental upper limit of 350 mg and some products had directions that could raise intake further.

Integrity

Full reviews

#1 - Best Overall

Sports Research Magtein Magnesium L-Threonate 2000mg 90 Count

Buyer Score 99/100Integrity Score 73/100Sports Research

Overview

This is a 90-count vegan capsule supplement providing a daily serving of three capsules with food. The matching Supplement Facts panel lists 2,000 mg magnesium L-threonate, branded Magtein, delivering 144 mg elemental magnesium, or 34% Daily Value. The other listed ingredients are hypromellose capsule, rice flour, and rice hulls. Its intended use is brain and sleep support, rather than treatment of a medical condition. The dose is concrete and matches the 2 g daily amount used in a small randomized cognition study of a different Magtein-based formula that also included phosphatidylserine and vitamins C and D. The manufacturer states that this product is third-party tested and made to cGMP standards, but a current product-specific laboratory report was not publicly available for review.

What works

• The daily label clearly distinguishes 2,000 mg of magnesium L-threonate from 144 mg elemental magnesium.
• It uses Magtein magnesium L-threonate and a daily amount represented in human research, though the research formula was not identical.
• There are no added melatonin, botanicals, vitamins, or proprietary sleep blends that could create extra sedative stacking.
• The listed capsule and filler ingredients are short and compatible with a vegan diet.

What does not

• No current lot-matched, independently issued certificate of analysis was publicly available to confirm potency, heavy metals, or microbiological results for a bottle in circulation.
• The exact product was not found in the current NSF Certified for Sport listing for Sports Research, which lists only its creatine product. No exact-product USP verification was located.
• The product warning advises medical consultation, but does not give practical label timing for antibiotics or osteoporosis medicines, or specifically flag kidney impairment.
• Its statement that this is the only magnesium form that crosses the blood-brain barrier goes beyond the limited human evidence available for the finished product.

Who is it for

This product suits an adult who specifically wants a plain magnesium L-threonate capsule, prefers vegan and gluten-free labeled ingredients, and can manage three capsules daily with food. It is most relevant for someone seeking a 2 g Magtein serving that resembles doses used in small human studies of cognition or sleep-related outcomes. It also suits buyers who value a clearly stated elemental magnesium amount, 144 mg daily, rather than assuming that the 2,000 mg compound weight is all magnesium.

Who is it not for

It is not designed for children or for people looking to correct a substantial magnesium shortfall, because the serving supplies 144 mg elemental magnesium rather than a high-dose mineral regimen. People with impaired kidney function, pregnancy or nursing, a medical condition, or regular prescription use should seek clinician guidance first. This is especially important with tetracycline or quinolone antibiotics, oral bisphosphonates, diuretics, and long-term acid-suppressing medicines. Athletes needing a banned-substance certification should use a product with an exact current registry match.

Integrity

The product has a transparent basic formula. Its matching label identifies the elemental magnesium amount, compound amount, serving size, and inactive ingredients. It contains no added sleep botanicals, melatonin, or stimulant ingredients. Sports Research states that the product is third-party tested and cGMP compliant, and its own product page gives a company contact and use direction. Those manufacturer statements are not the same as public lot-specific proof. The certification check did not find this magnesium product in Sports Research's current NSF Certified for Sport listing, which shows only creatine. No publicly accessible lot-specific report was found for identity, elemental potency, heavy metals, or microbiological testing. FDA recall and warning-letter resources searched did not identify a product-specific action. Packaging is a conventional capsule bottle, and no bottle-material, recycling, refill, or other substantiated environmental information was found.

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#2 - Hot Deal

Double Wood Supplements Magnesium L Threonate 2000mg

Buyer Score 96/100Integrity Score 81/100Double Wood Supplements

Overview

This is a 120-capsule magnesium L-threonate product in gelatin capsules. The current manufacturer label sets one serving at four capsules, up to four capsules daily, so the bottle supplies 30 daily servings. Each daily serving is labeled as 2,000 mg of Magtein magnesium L-threonate, providing 144 mg elemental magnesium. Other ingredients are gelatin, rice flour, and vegetable stearate. The product has unusually concrete quality documentation for this category. The NSF registry lists Double Wood Magnesium L-Threonate as a certified finished product, although its registry entry shows an eight-capsule recommended serving. A manufacturer-posted January 2025 lot report covers potency, metals, microbes, capsule weight, and disintegration. It reported 2,542.4 mg L-threonate and 162.3 mg elemental magnesium per four capsules, above both the label declaration and the report's stated upper compound specification. Human trials have used Magtein at 2 g daily, but cognitive and sleep evidence remains limited in size and scope.

What works

• The label clearly separates the 2,000 mg Magtein compound amount from 144 mg elemental magnesium.
• NSF's public registry lists Magnesium L-Threonate as a certified finished product for Double Wood.
• The published lot report includes lead, arsenic, cadmium, mercury, microbial screens, potency, and disintegration.
• There are no added sedatives, botanicals, vitamins, or proprietary blends that could complicate sleep or cognitive ingredient safety.

What does not

• Four capsules are required for the labeled daily serving, and the bottle is a 30-day supply at that use level.
• The current published lot report measured more L-threonate and elemental magnesium than the label declares, including a compound result above the report's stated specification range.
• The label advises consulting a physician but does not specifically explain kidney-risk, diarrhea risk, or dose separation from antibiotics and bisphosphonates.
• The product page makes broad brain-magnesium and cognitive-support claims, while the human evidence is still limited and some trials were industry funded.

Who is it for

This product suits an adult specifically seeking the patented Magtein form at the 2 g daily amount used in a recent six-week randomized trial, rather than a general high-elemental-magnesium supplement. It also fits someone willing to take four capsules daily and who values a publicly listed NSF certification plus a posted batch report. It is most appropriate for a person using it as a limited-evidence sleep or cognitive support supplement, not as treatment for insomnia, memory loss, or a neurological condition.

Who is it not for

It is not suited to people with kidney impairment or kidney failure unless their clinician directs its use, because impaired kidneys increase magnesium-toxicity risk. People taking oral antibiotics or bisphosphonates need individualized timing advice, since magnesium can reduce absorption. It is also unsuitable for vegetarians, vegans, or households avoiding gelatin. Anyone seeking substantial magnesium replacement may prefer a product selected for elemental magnesium, since this labeled daily serving supplies 144 mg. Pregnant, nursing, medically complex, or medication-using consumers should seek clinician guidance first.

Integrity

The strongest product-specific quality signal is the live NSF registry listing for Double Wood Magnesium L-Threonate. The manufacturer also posts a lot-numbered report for lot 2532202, manufactured in January 2025, with quantified heavy metals and passed microbial and disintegration tests. The lead result was 0.235 micrograms per serving, below the report's 0.5 microgram limit. The report is useful, but it is hosted by the manufacturer and its potency result exceeds the stated compound specification range. The capsule contains gelatin, plus rice flour and vegetable stearate, so it is not vegetarian. No refill system, bottle-resin identification, recycled-content claim, or recycling instructions were found. Double Wood received an FDA warning letter in 2020 over disease-like claims for a different hangover product. California lead notices and a settlement involved several other Double Wood botanical products, not this magnesium product. Those actions do not establish a contaminant finding for this product, but they are relevant to the brand's wider compliance record.

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#3

Nutricost Magnesium L-Threonate 2000mg, 120 Count

Buyer Score 92/100Integrity Score 80/100Nutricost

Overview

Nutricost Magnesium L-Threonate is an adult capsule supplement with 120 capsules, or 40 three-capsule servings. The label directs one capsule in the morning and two capsules two hours before sleep. A retailer-hosted label panel confirms that the daily serving provides 2,000 mg Magtein magnesium L-threonate, including 144 mg elemental magnesium. It is a single-active formula. The listed nonactive ingredients are a hypromellose capsule, microcrystalline cellulose, vegetable magnesium stearate, and silica, with no melatonin, botanicals, or other sleep and cognitive actives. Nutricost states that it uses independent ISO-accredited laboratory testing, but no current lot-matched report was publicly available for review. The manufacturing facility, not this finished product, appears in NSF's current dietary-supplement GMP listing.

What works

• The label clearly distinguishes 2,000 mg Magtein compound weight from 144 mg elemental magnesium per daily serving.
• The 2,000 mg daily Magtein amount matches a six-week randomized trial in adults with self-reported dissatisfied sleep, although that study was industry funded.
• No added melatonin, sedating botanicals, vitamins, or cognitive blends are listed, which reduces combination-ingredient uncertainty.
• Nutricost Manufacturing is listed by NSF under NSF/ANSI 455-2 for dietary-supplement GMP operations, including encapsulation and quality-unit activities.

What does not

• The manufacturer states that the product is third-party tested, but no public, lot-specific certificate of analysis was found to confirm potency, heavy metals, or microbiological results for a purchased bottle.
• No exact-product USP, NSF dietary-supplement, NSF Certified for Sport, Informed Sport, or BSCG certification was identified. Facility GMP certification is not finished-product certification.
• The label advises medical consultation for prescription medicines and medical conditions, but does not specifically explain kidney-risk precautions or medicine spacing for antibiotics and oral bisphosphonates.
• Human evidence is still limited. The dose matches a short six-week trial in adults aged 18 to 45 with dissatisfied sleep, rather than establishing treatment for insomnia, memory disease, or broad cognitive impairment.

Who is it for

This product suits adults age 18 and over who specifically want the Magtein form of magnesium L-threonate, prefer capsules, and can manage a three-capsule daily routine. Its 2,000 mg Magtein serving matches the amount used in a recent six-week placebo-controlled study of healthy younger adults with self-reported dissatisfied sleep. It is also a straightforward option for people who prefer not to combine magnesium with melatonin, herbs, or multiple brain-focused ingredients. People using regular medicines should first confirm timing and suitability with a pharmacist or clinician.

Who is it not for

It is not designed for children, pregnancy, or breastfeeding, as the label advises against those uses. People with kidney impairment or kidney failure should not self-start magnesium supplementation because reduced magnesium clearance raises toxicity risk. It is also unsuitable for anyone seeking a product with publicly available lot-specific contaminant and potency results, or exact-product independent certification. People taking tetracycline or quinolone antibiotics, oral bisphosphonates, diuretics, or long-term acid-suppressing medicines need individualized advice, including whether doses should be separated.

Integrity

The label provides a useful distinction between the 2,000 mg magnesium L-threonate compound amount and 144 mg elemental magnesium. It also limits the formula to Magtein plus ordinary capsule excipients, rather than adding melatonin or sedating botanicals. The manufacturer-stated directions include adult-only use, pregnancy and breastfeeding exclusions, and consultation for medicines or medical conditions. Magnesium supplements can cause gastrointestinal effects, and impaired kidney function increases the risk of excess magnesium. Nutricost Manufacturing is currently listed by NSF to the dietary-supplement GMP standard, which supports traceability of the manufacturing site and quality-system oversight. That listing does not certify the contents of this individual product. The manufacturer states it uses independent ISO-accredited testing, but a current lot-linked report was not public. The bottle format is conventional plastic packaging. No refill system, packaging-material specification, recycling instructions, or substantiated environmental claim was identified.

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#4

Nutricost Magtein Magnesium L-Threonate 2000mg

Buyer Score 88/100Integrity Score 79/100Nutricost

Overview

This is a 90-capsule magnesium L-threonate supplement for adults. A full serving is three vegetarian capsules, taken as one in the morning and two about two hours before sleep. The bottle provides 30 servings. The independently listed Supplement Facts panel states 2,000 mg Magtein magnesium L-threonate and 144 mg elemental magnesium per daily serving. It is a single-active formula, apart from capsule and processing ingredients including hypromellose, microcrystalline cellulose, vegetable-source magnesium stearate, and silica. The label warns about possible drowsiness or headache and directs people using prescriptions or managing a medical condition to consult a clinician. The manufacturer states that it is third-party tested by ISO-accredited laboratories, but a current lot-matched finished-product report was not publicly available for review.

What works

• The daily label clearly separates 2,000 mg of magnesium L-threonate from 144 mg elemental magnesium.
• The formula contains no added melatonin, sedative herbs, vitamins, or proprietary cognitive blend ingredients.
• The 2 g daily Magtein amount matches the magnesium L-threonate amount used in a placebo-controlled human cognition study, although that study used a combination formula.
• The current NSF registry lists Nutricost Manufacturing facilities for dietary-supplement GMP certification, including capsule manufacturing capabilities.
• The product label provides adult-use, pregnancy and breastfeeding, medication, drowsiness, and tamper-seal warnings.

What does not

• No public, lot-specific certificate of analysis was found to confirm this bottle's potency, heavy metals, or microbiological results.
• The claimed ISO-accredited third-party testing is manufacturer-stated, without a named laboratory, report, lot number, methods, or contaminant limits available to buyers.
• The label does not give practical spacing directions for antibiotics or oral bisphosphonates, despite known magnesium interactions.
• It does not specifically flag kidney impairment, where magnesium toxicity risk rises because clearance can be reduced.
• No finished-product certification match was located in major public USP, NSF dietary supplement, Informed Sport, or BSCG registries.

Who is it for

This fits an adult who specifically wants Magtein-branded magnesium L-threonate rather than a broad sleep blend, and who values a label that makes the compound weight and elemental magnesium intake easy to distinguish. The 30-day bottle and three-capsule routine suit a person prepared to take a divided daily dose. It is also relevant to vegetarian and gluten-avoiding users based on the product's stated formulation. The human evidence is most applicable to generally healthy adults, not to treatment of a diagnosed cognitive or sleep disorder.

Who is it not for

This is not appropriate for children, pregnancy, or breastfeeding under the product's own warning. People with kidney disease or reduced kidney function should not self-start magnesium without clinician input. Anyone taking tetracycline or quinolone antibiotics, oral bisphosphonates, diuretics, or other regular medicines needs pharmacist or prescriber advice, including dose timing. It also does not suit buyers who require publicly accessible, lot-matched heavy-metal and microbiology results, or an exact finished-product certification from USP, NSF, Informed Sport, or BSCG.

Integrity

The product's strongest health attribute is formula simplicity. The listed active is Magtein magnesium L-threonate, providing 144 mg elemental magnesium per serving, with no added melatonin, botanical sedatives, phosphatidylserine, or added vitamins. The label's 2 g daily compound amount aligns with the dose used in at least one controlled human cognition study, but that study tested a formula that also included phosphatidylserine and vitamins, so it does not establish the same outcome for this exact product. Nutricost Manufacturing appears in NSF's current GMP facility registry for dietary supplements. This supports manufacturing-system traceability, but it is not certification of this finished product. The brand states that ISO-accredited laboratories perform third-party testing, yet no public lot-specific report was located. The bottle uses a conventional capsule supplement format, and no specific recycled-content, recyclability, refill, or other substantiated environmental packaging claim was found. No relevant public FDA recall or warning-letter signal was located in the checked databases.

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#5

Metagenics Magtein Magnesium L-Threonate Supplement

Buyer Score 87/100Integrity Score 82/100Metagenics

Overview

This is a 120-capsule magnesium L-threonate product for adults. The labeled routine is three capsules daily, one in the morning and two about two hours before bedtime, so a bottle supplies 40 days at the recommended use. The manufacturer lists 2 g of Magtein magnesium L-threonate and 147 mg elemental magnesium per daily dose, with no added vitamins, herbs, melatonin, or other sleep ingredients. Its formula and dose are unusually easy to interpret. The 2 g daily Magtein amount matches the dose used in recent randomized trials of Magtein, although those studies do not establish that this finished product itself improves memory, learning, or sleep. Metagenics states that batches receive third-party testing, but a current lot-matched independent report for this product was not publicly available for review.

What works

• The Supplement Facts panel distinguishes 2 g magnesium L-threonate from 147 mg elemental magnesium at the full daily dose.
• The three-capsule daily amount matches the 2 g Magtein dose used in randomized human cognition and sleep research.
• No added sedatives, botanicals, vitamins, or proprietary cognitive blend complicate ingredient safety.
• Metagenics manufacturing facilities are listed by NSF as certified to NSF/ANSI 455-2 GMP requirements for dietary supplements.
• The manufacturer provides a specific pregnancy, nursing, medication-use, and child-safety caution.

What does not

• The label does not give practical timing instructions for antibiotics or bisphosphonates, despite known magnesium interactions.
• It does not specifically flag kidney impairment, where the risk of magnesium toxicity is higher, or describe possible gastrointestinal effects.
• Metagenics states that finished products are third-party tested, but no public, lot-matched report identifying the laboratory and results was available to verify potency, metals, or microbes.
• The brain, memory, learning, and cognitive-support positioning reaches beyond what can be concluded for this exact finished product from the limited, partly industry-funded Magtein trials.
• The bottle material and product-specific recycling instructions are not clearly disclosed.

Who is it for

This product fits an adult who specifically wants the branded Magtein form of magnesium L-threonate, prefers a simple formula without melatonin or botanical sedatives, and can manage three capsules per day. It is most relevant for someone discussing cognitive or sleep-support supplementation with a clinician, particularly because its 2 g daily compound dose matches recent human Magtein research. The 120-capsule bottle lasts about 40 days at the labeled routine, so it also suits buyers comfortable with that dosing schedule and product cost.

Who is it not for

It is not well suited to children, people who are pregnant or nursing without clinician guidance, or anyone with kidney disease or impaired kidney function unless their prescriber approves it. People taking tetracycline or quinolone antibiotics, oral bisphosphonates, diuretics, or other regular medicines need pharmacist or clinician advice on suitability and timing. It is also a poor fit for buyers seeking a publicly accessible, lot-specific independent certificate covering potency, heavy metals, and microbiological quality, because that proof was not available to inspect.

Integrity

The health positives are a transparent active formula and a daily amount that separates compound weight from elemental magnesium. At 147 mg supplemental magnesium daily, it remains below the adult 350 mg upper limit for magnesium from supplements and medicines. That does not remove interaction or kidney-risk concerns. Magnesium can reduce absorption of certain antibiotics and oral bisphosphonates, and impaired renal function raises toxicity risk. Metagenics has an independently listed NSF/ANSI 455-2 GMP-certified manufacturing operation, which supports facility-level quality controls but is not an independent certification of this exact product. The company also states that it tests finished products for contaminants and potency, yet publicly reviewable lot-level results were unavailable. Metagenics' parent is a certified B Corporation, and the company reports recyclable paper shipping materials and recycled cardboard. Those are company-level practices, not proof that this capsule bottle is recycled or recyclable locally.

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#6

Magnesium L-Threonate Complex with Apigenin and L-theanine

Buyer Score 84/100Integrity Score 71/100Why Not Natural

Overview

This is a 90-capsule, 30-day adult capsule product. The daily direction is three capsules, supplying 1,000 mg magnesium L-threonate branded Magtein, including 72 mg elemental magnesium, plus 250 mg L-theanine and 50 mg apigenin. These amounts and the vegetable capsule are independently documented in the NIH Dietary Supplement Label Database and on the manufacturer label. It is positioned for relaxation, sleep, mood, and cognitive support. The 1,000 mg Magtein amount matches a short 21-day human sleep trial, though that does not establish that this three-ingredient product improves sleep or cognition for every user. The manufacturer says finished batches are tested for potency, heavy metals, and other contaminants and that a batch-specific report can be requested. A current report, laboratory identity, and results for this product were not publicly available during verification.

What works

• The label clearly separates 1,000 mg magnesium L-threonate from its 72 mg elemental magnesium contribution.
• All three active ingredients have disclosed daily amounts, rather than appearing in a proprietary blend.
• The daily Magtein amount matches the amount used in one 21-day randomized sleep study of magnesium L-threonate.
• The manufacturer states that buyers can request batch-specific testing for potency and contaminants using the bottle batch number.
• The formula lists vegetable capsules as the only other ingredient.

What does not

• The directions do not specifically address kidney impairment, diarrhea or abdominal effects, or timing around antibiotics and osteoporosis medicines that can interact with magnesium.
• Apigenin and L-theanine are fully dosed, but the product does not give ingredient-specific cautions about combining calming supplements or medicines.
• No current public certificate of analysis, identified laboratory, or finished-product contaminant results were located.
• No exact-product certification was located in the USP, NSF, Informed Sport, or BSCG public registries.
• The brand recalled a different moringa capsule product in January 2026 after an FDA-linked Salmonella outbreak. This magnesium product was not named in that recall, but the event weakens confidence in brand-wide quality controls.

Who is it for

This product suits an adult who specifically wants a capsule formula with disclosed amounts of Magtein, L-theanine, and apigenin, rather than a proprietary sleep blend. It may fit someone testing short-term relaxation or sleep support who can tolerate taking three capsules daily and who wants only 72 mg of supplemental elemental magnesium. It is most appropriate for a person who can request and review the current bottle's batch report before regular use, especially if contaminant verification is important to them.

Who is it not for

It is not a casual choice for people with kidney disease, reduced kidney function, pregnancy or breastfeeding, or complex medication schedules without clinician review. Magnesium can interfere with absorption of certain antibiotics and oral bisphosphonates, and the label does not provide spacing instructions. It is also a poor fit for someone already using several sedating or calming products, or for anyone seeking proven treatment for insomnia, anxiety, memory loss, dementia, or another medical condition. Children should use an age-appropriate product under pediatric guidance.

Integrity

The product's strongest transparency point is its Supplement Facts panel. It specifies the Magtein compound amount, elemental magnesium contribution, L-theanine, apigenin, serving size, and vegetable capsule. The manufacturer states that its products are made in the United States and that bottle-specific reports covering potency, heavy metals, and other contaminants are available on request. That is useful access, but it is not the same as a publicly posted, lot-matched report from an identified accredited laboratory. No exact-product certification was found in major independent certification registries, and no specific recycling instructions or lower-waste packaging information were found. The brand's January 2026 recall involved a separate moringa capsule, not this magnesium product, after Salmonella contamination linked to moringa powder. It does not establish contamination of this formula, but it is relevant context for buyers who prioritize demonstrated finished-product microbiological controls.

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#7

ForestLeaf Magnesium L-Threonate 2000mg Supplement

Buyer Score 82/100Integrity Score 75/100ForestLeaf

Overview

This is a 90-capsule magnesium L-threonate product intended for adults. The manufacturer directs three capsules once daily with food, providing 2,000 mg of Magtein magnesium L-threonate and 144 mg elemental magnesium, or 34% of the Daily Value. The bottle therefore supplies 30 daily servings. The formula is unusually clear about compound weight versus elemental magnesium, and contains no added melatonin, herbs, vitamins, or other sleep and cognitive actives. Its 2 g daily Magtein amount matches a six-week randomized trial in 100 adults aged 18 to 45 with dissatisfied sleep. That study reported some cognitive and subjective sleep-related improvements, but was funded by the ingredient company and did not show objective sleep improvements. ForestLeaf states it tests lots through independent labs, but no lot-matched report or exact-product certification registry entry was available for verification.

What works

• The Supplement Facts panel clearly distinguishes 2,000 mg Magtein magnesium L-threonate from 144 mg elemental magnesium.
• The daily 2 g Magtein amount matches the dose used in a six-week randomized trial in adults with dissatisfied sleep.
• No added sedatives, botanicals, or undisclosed cognitive blend complicate interaction or stacking risk.
• The manufacturer provides adult directions, pregnancy and nursing caution, prescription-medication caution, a customer contact, and a stated U.S. GMP-compliant facility claim.

What does not

• The directions do not specifically address kidney impairment, diarrhea or stomach effects, or the needed spacing from tetracycline and quinolone antibiotics and oral bisphosphonates.
• ForestLeaf claims independent testing and lot testing for heavy metals and microbiology, but does not publish a current lot-specific certificate of analysis with results, laboratory identity, or test methods.
• No current exact-product certification was located in the checked USP, NSF, Informed Sport, or BSCG registries.
• Marketing claims that it has the highest absorption, raises brain magnesium, and boosts performance extend beyond the limited human evidence for this finished product.

Who is it for

This product fits an adult who specifically wants the Magtein magnesium L-threonate form, prefers a formula without melatonin or botanical sleep ingredients, and is comfortable taking three capsules daily. It is most relevant to someone seeking a magnesium product whose compound and elemental doses are both disclosed, rather than interpreting a large compound-weight number as elemental magnesium. The 30-day supply may also suit a person planning a time-limited, clinician-informed trial for general cognitive or sleep-related support, not treatment of a diagnosed condition.

Who is it not for

It is not suited to children, or to people who are pregnant or nursing without clinician approval. People with kidney disease, reduced kidney function, recurrent diarrhea, or a history of high magnesium levels should seek medical guidance before use. Anyone using tetracycline or quinolone antibiotics, oral osteoporosis medicines such as alendronate, diuretics, or long-term proton-pump inhibitors needs medicine-specific timing or monitoring advice. It is also a poor fit for buyers who require a publicly available lot-specific contaminant report or current independent finished-product certification.

Integrity

The useful health detail is the transparent dose declaration. Each daily serving supplies 144 mg elemental magnesium from 2,000 mg Magtein magnesium L-threonate. That supplemental magnesium amount is below the adult 350 mg upper limit, but magnesium can still cause gastrointestinal effects and presents greater toxicity risk when kidney function is impaired. The label's broad prescription-medication caution is appropriate but incomplete because it does not give spacing instructions for several known interacting medicines. ForestLeaf states that the product is made in a U.S. GMP-compliant facility and that every lot is independently tested for heavy metals and microbiological components. Those are manufacturer statements, not independently verifiable finished-product results. No active recall, regulator warning, or California Proposition 65 exposure warning for this product was located in the checked public sources. The packaging is a 90-capsule bottle, but ForestLeaf provides no material, recyclability, refill, or substantiated environmental claim for this product.

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#8

Micro Ingredients Magtein Magnesium Formula

Buyer Score 81/100Integrity Score 64/100Micro Ingredients

Overview

This is a lemonade-flavored, sugar-free magnesium powder in a 180 g jar. The manufacturer describes a three-scoop serving as 1,000 mg Magtein magnesium L-threonate plus 2,687 mg magnesium glycinate, providing 400 mg elemental magnesium. It is intended to be mixed into a beverage for calm, focus, relaxation, and sleep support. The stated formula uses branded Magtein, a magnesium L-threonate ingredient that has been used in small human cognition and sleep trials. However, the studied daily amount was commonly 2 g of Magtein, while this product lists 1 g per three-scoop serving. Directions also say to use that serving one or two times daily, which creates a meaningful 400 mg to 800 mg daily supplemental-magnesium range. The manufacturer states that ingredients are third-party tested, but it does not publish a lot-specific report, testing laboratory, or finished-product contaminant results.

What works

• The manufacturer clearly states 400 mg elemental magnesium per three-scoop serving.
• Uses branded Magtein magnesium L-threonate alongside magnesium glycinate, rather than an undisclosed proprietary blend.
• The 1 g Magtein amount per serving is concrete enough to compare with human research doses.
• No added melatonin, botanicals, or other sedative-style active ingredients were identified in the stated formula.

What does not

• The direction to take one or two three-scoop servings daily can raise supplemental magnesium from 400 mg to 800 mg daily. Both amounts exceed the NIH adult upper limit of 350 mg for magnesium from supplements unless clinician-directed.
• The product page does not provide practical timing guidance for antibiotics, oral bisphosphonates, or other medicines that can interact with magnesium.
• Third-party testing is a manufacturer claim only. No lot-specific certificate of analysis, laboratory identity, or heavy-metal and microbiological result was publicly available.
• Its brain, focus, and sleep marketing goes beyond the limited evidence for the finished blend. Human Magtein studies generally used 2 g daily, and sleep results have been mixed.
• The environmental language is vague. “All Eco-Certified” does not identify a certifier, packaging material, recycled content, or recycling instructions.

Who is it for

This product fits an adult who specifically wants a flavored drink powder containing both magnesium glycinate and branded Magtein, and who can measure three scoops accurately. It is most relevant to someone seeking a magnesium supplement for general dietary support and who understands that the brain and sleep claims are not established treatment claims. A buyer should be prepared to start conservatively, account for magnesium from other supplements or antacids, and review the dose with a clinician or pharmacist if they use regular medicines.

Who is it not for

It is not suited to children, people with kidney impairment or kidney failure, or anyone who has been told to limit magnesium without clinician direction. It is also a poor fit for people taking tetracycline or quinolone antibiotics, oral bisphosphonates, diuretics, or long-term acid-reflux medicines unless a pharmacist provides timing and monitoring advice. People seeking independently certified quality, a public lot-matched contaminant report, or a formula that directly matches the 2 g daily Magtein research dose should choose a product with that evidence available.

Integrity

The notable formulation point is the use of Magtein magnesium L-threonate, a branded ingredient that has appeared in small human trials. Those trials used about 2 g daily and found selective cognitive or self-reported sleep findings, not consistent proof of better sleep or broad cognitive performance. The product's stated 400 mg elemental-magnesium serving is already above the NIH adult upper limit for supplemental magnesium, and the listed option of two servings daily makes medication review and kidney safety especially important. The manufacturer says its ingredients are third-party tested and uses non-GMO and eco-oriented marketing. Those claims were not supported by a public lot-specific certificate, named independent laboratory, finished-product heavy-metal panel, microbiological report, or exact-product certification listing. No product-specific FDA recall, warning letter, or California exposure warning was located in the reviewed sources. Packaging materials, recycled content, refill availability, and recycling directions were not clearly disclosed.

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#9

Integrative Therapeutics Magtein Brain Function Supplement

Buyer Score 78/100Integrity Score 79/100Integrative Therapeutics

Overview

This is a 90-capsule, 30-day magnesium L-threonate product for adults. The daily serving is three capsules, taken as one in the morning and two about one hour before bed. The manufacturer lists 2,000 mg of Magtein magnesium L-threonate, supplying 144 mg elemental magnesium, plus 60 mg vitamin C and 10 mcg vitamin D3 per serving. The 2 g daily Magtein amount matches the dose used in a 30-day placebo-controlled study of a related formulation in healthy Chinese adults, although that study also included phosphatidylserine and therefore does not directly test this exact product. The manufacturer states that it tests raw-material lots and finished goods, but no current buyer-accessible, lot-matched independent certificate of analysis was located.

What works

• The Supplement Facts panel clearly separates 2,000 mg magnesium L-threonate from its 144 mg elemental magnesium contribution.
• The daily Magtein amount aligns with the 2 g dose used in a human cognitive study of a related formula.
• Added vitamin C and vitamin D3 are fully disclosed and modestly dosed, without sedative herbs or melatonin.
• Manufacturer directions include divided dosing and caution people who are pregnant, nursing, have kidney disease, or use medicines.
• The manufacturer states that its internal laboratory holds ISO/IEC 17025 accreditation and that finished goods are tested for label and shelf-life expectations.

What does not

• No live exact-product listing was located in the major independent product-certification registries reviewed.
• No lot-specific independent report was available to buyers for potency, heavy metals, microbes, or other contaminants.
• The warning to consult a professional for medicines is broad. It does not explain that magnesium can reduce absorption of tetracycline and quinolone antibiotics or oral bisphosphonates when taken too close together.
• The cognitive evidence is limited and does not establish that this exact vitamin C and vitamin D3 formula improves memory for all adults.
• No specific bottle-material, recyclability, refill, or substantiated lower-waste packaging information was found.

Who is it for

This product fits an adult who specifically wants magnesium L-threonate rather than a higher-elemental-magnesium product, and who can follow a three-capsule daily routine with an evening dose. It is most relevant for someone seeking modest cognitive or sleep-related support while understanding that the human research is still limited and does not prove benefit from this exact formula. The 30-serving bottle and $42 listed price suit a one-month trial period, ideally with clinician input if the person has a complex medication regimen.

Who is it not for

It is not appropriate for children, or for people who are pregnant or nursing, because the product label advises against use in pregnancy and nursing and says it is not formulated for children. People with kidney disease should not self-start it without clinician advice because impaired kidneys raise the risk of magnesium accumulation. It is also a poor fit for anyone needing a high magnesium dose for a clinician-directed indication, requiring a lot-specific contaminant report, or taking antibiotics or oral osteoporosis medicines without a plan to separate doses.

Integrity

The formula has a transparent active-ingredient panel. Each daily serving lists 144 mg elemental magnesium from 2,000 mg Magtein magnesium L-threonate, along with vitamin C and vitamin D3. It contains no declared melatonin, valerian, apigenin, or other sedating brain ingredients. Its pregnancy, nursing, kidney-disease, and medication consultation warning is useful, though consumers taking tetracycline or quinolone antibiotics or oral bisphosphonates need more specific timing guidance from a clinician or pharmacist. The manufacturer reports an ISO/IEC 17025-accredited internal laboratory and testing of raw materials and finished products. That supports process traceability, but it is not the same as public, lot-matched independent finished-product testing. No exact-product independent certification or public lot certificate was found in the reviewed registries and sources. No specific environmental packaging claim, recycling instruction, refill option, or packaging-material disclosure was found, so waste and end-of-life handling remain unclear.

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#10

Designs for Health NeuroMag Magnesium L-Threonate Supplement

Buyer Score 76/100Integrity Score 76/100Designs for Health

Overview

NeuroMag is a 90-capsule vegan magnesium L-threonate product intended for adult brain and cognitive support. The stated daily use is three capsules, providing 145 mg elemental magnesium from 2 g of Magtein magnesium L-threonate, so one bottle supplies 30 daily servings. Its listed inactive ingredients are a cellulose capsule, dicalcium phosphate, vegetable stearate, and microcrystalline cellulose. The formula is unusually simple, with no melatonin, herbs, amino acids, or added vitamins that could create sedative stacking. The 2 g Magtein daily amount is important because it matches the dose used in recent randomized studies of Magtein, although the evidence base remains limited and some research involved industry affiliations or formulations that included other nutrients. The label's stronger brain-delivery language goes beyond what buyers can treat as established clinical proof for this exact finished product.

What works

• The daily label clearly distinguishes 145 mg elemental magnesium from 2 g magnesium L-threonate.
• It uses Magtein magnesium L-threonate at the 2 g daily amount studied in randomized human research.
• It contains no added sleep aids, botanicals, melatonin, or other cognitive actives.
• The simple inactive ingredient list is compatible with vegan, gluten-free, dairy-free, and soy-free dietary preferences, based on manufacturer and retailer labeling.

What does not

• The product directions mainly provide dose and storage information, not practical warnings about kidney impairment, diarrhea, pregnancy, or timing around interacting medicines.
• No current public, lot-matched certificate of analysis was located for identity, elemental magnesium, heavy metals, or microbiological testing.
• The exact product was not found in the live NSF, USP, Informed Sport, or BSCG finished-product certification registries. NSF lists a distinct NeuroMag Sport product instead.
• Claims about superior blood-brain-barrier delivery and cognitive support are broader than the still limited clinical evidence for the exact finished product.

Who is it for

This product suits an adult specifically seeking a standalone magnesium L-threonate formula, rather than a general high-dose magnesium supplement or a multi-ingredient sleep blend. It is most relevant for someone comfortable taking three capsules daily for a 30-day supply and who wants the same 2 g Magtein amount used in several short randomized studies of cognition and sleep-related outcomes. It may also fit people avoiding animal-derived capsule materials and common allergens listed as excluded by the manufacturer.

Who is it not for

It is not a good self-directed choice for people with significant kidney disease, unexplained weakness, or a history of magnesium-related adverse effects, because impaired kidney clearance can raise magnesium risk. People taking oral bisphosphonates, tetracycline or quinolone antibiotics should seek pharmacist or clinician guidance on separating doses. Pregnant or breastfeeding people, children, and people managing insomnia, memory loss, dementia, or another medical condition should not treat this supplement as a substitute for medical assessment or treatment.

Integrity

The formula avoids a common safety issue in brain and sleep supplements, namely hidden combinations of melatonin, sedative herbs, or multiple psychoactive ingredients. Its label makes both the magnesium L-threonate compound amount and elemental magnesium amount available, which helps prevent confusion between the two. NIH notes that magnesium can interact with oral bisphosphonates, tetracycline antibiotics, and quinolone antibiotics, and that people using regular medicines should discuss magnesium intake with a clinician. Public certification registries did not show the exact NeuroMag product as independently certified. NSF does list a separate NeuroMag Sport product, which should not be treated as certification of this product. A retailer describes independent potency and purity testing, but no buyer-accessible, lot-specific report was located. No specific FDA recall, warning letter, or California Proposition 65 warning for NeuroMag was located in the reviewed sources. Packaging material, recycling instructions, refill options, and substantiated environmental claims were not disclosed, so its environmental footprint cannot be meaningfully verified.

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