Alpha Brain Black Label Review 2026

We think 5.5 is fair. What holds Black Label back is less how much Onnit put in than what it chose to put in. Citicoline, theanine and the Lutemax lutein are at the amounts their studies used, and every dose is printed, something the original Alpha Brain can't say. But the biggest ingredient, 1,000 mg of velvet bean, has no trial for focus or memory in healthy people, so it earns nothing for its dose. Four more fall short, from huperzine A at half our benchmark to lion's mane at 1,300 mg under it.

Testing scores zero. Onnit puts a "COA Tested" badge on the product page without linking a certificate, and no testing program lists the product, so one published report on a finished batch could add up to a full point.

The supplement facts panel on Onnit's product page matches all eight amounts in our records, with four capsules a serving and 20 servings in the 80-capsule bottle, and the other ingredients are a vegetarian capsule, microcrystalline cellulose, L-leucine, maltodextrin, silica and sucrose.¹ The ingredient list in the page text is shorter, though. It names six ingredients and leaves out the lion's mane and caffeine, so the panel image is the one place on Onnit's site to see the whole formula.²

The directions are four capsules daily or as needed with a light meal, and no more than four in 24 hours, which means a bottle lasts 20 days if you take it every day. Onnit says to skip Black Label if you're already taking the original, and that it isn't for anyone pregnant, breastfeeding or under 18.²

Velvet bean is 1,000 mg of seed extract standardized to 15 percent L-dopa, which works out at 150 mg of L-dopa a serving. L-dopa is what the brain makes dopamine from, and it's the same molecule as levodopa, the Parkinson's drug, and its L-dopa evidence comes from Parkinson's trials. In one, eight patients took single doses of 15 g and 30 g of mucuna against a standard levodopa tablet,¹² and in another, 18 patients took roasted-seed powder dosed by body weight.¹⁸

We found no randomized trial of mucuna for memory, focus or mood in healthy people,¹⁹ and the nearest evidence isn't encouraging. When 63 healthy adults aged 65 to 75 took 100 mg of L-dopa before each of 20 brain-training sessions, they improved slightly less at spatial reasoning than the placebo group.²⁰ That trial added a drug that stops L-dopa breaking down before it reaches the brain, and Black Label doesn't have one, so it isn't a direct match, but it's the closest test of the idea we could find.

Lion's mane is 500 mg of mycelium and fruiting body with no extract strength printed, and that's 1,300 mg short of the 1,800 mg we use as its benchmark. That amount comes from a four-week trial in 41 healthy adults, who were quicker on one attention test an hour after a dose.³ The trial in older adults with mild memory decline used more, about 2,880 mg of dried fruiting body a day for 16 weeks.²¹ The one trial we found of a mix like Black Label's, mycelium and fruiting body together, gave 10 healthy adults 2 g a day and found no significant change.²² At a quarter of that amount, we wouldn't expect much from it here.

Citicoline is 250 mg of Cognizin, the branded form and the amount used in a four-week trial of 60 women aged 40 to 60, who made fewer errors on an attention test than the placebo group.⁴ That's the bottom of the research range, though, and the memory result in older adults came at 500 mg a day.²³ Cognizin's maker supplied the citicoline for the first trial and paid for the second.

Phosphatidylserine is printed as 200 mg of SerinAid, and the label doesn't say whether that's 200 mg of phosphatidylserine or 200 mg of the SerinAid ingredient. It matters, because Transparent Labs Cognition prints the same 200 mg of SerinAid as 140 mg of phosphatidylserine. Either way it's short of the 300 mg we use as the benchmark,²⁴ and in a six-month trial of 78 older adults with memory complaints that also tried 100 mg, scores rose in every group, placebo included.⁵

Theanine is 100 mg, the smallest amount in its research range, and caffeine is 25 mg, about a quarter of a cup of coffee. That pairing is close to a trial where 44 young adults took 97 mg of theanine with 40 mg of caffeine and switched between tasks more accurately.²⁵ The caffeine here is 15 mg under that, though, and under the 40 mg where research reviews start to find better alertness.²⁶ The smallest single dose we found tested on its own was 32 mg,²⁷ so Black Label's caffeine is below any amount with a measured effect, although several reviewers still mention mild jitters.

Huperzine A is 200 mcg, from 20 mg of clubmoss extract at 1 percent. That's half the original Alpha Brain's amount and half the 400 mcg a day we use as the benchmark. That benchmark comes from Alzheimer's research, and in a 210-patient trial, the 70 taking 200 mcg twice a day saw no change,²⁸ while a review of 20 trials rated most of them low quality.²⁹ There's very little research in healthy adults, so this is a small amount of an ingredient whose case rests on people with dementia.

Lutein and zeaxanthin come as 24 mg of Lutemax 2020, inside the 13 to 27 mg a day used in a six-month trial of 59 young adults whose memory and attention scores improved.⁶ Lutemax's maker paid for that trial. Both carotenoids build up in the eye and brain over months, and the trials gave them every day for six months, which sits oddly with the way Onnit sells Black Label.

To be fair to Onnit, the label prints every amount along with the extract strengths and branded forms, and there's no blend hiding anything. That's a real step up from the original, where seven of the ten actives sit in blends without amounts.⁹

Alpha Brain Black Label against its closest matches

Shared ingredientsFull formula

Add a product to compare+ Add a productQualia MindMind Lab ProVyvamindAlpha BrainNeuroQ Memory & Focus Extra StrengthNooCube

Product	AAlpha BRAIN Black LabelThis review	×Transparent Labs Cognition	×Neutonic Productivity Drink	×Caffeine + L-Theanine 100 mg / 200 mg Capsules
Scientific audit	5.5/10	7.8/10	6.7/10	9.4/10
Buyer rating	8.4/10	9.7/10	8.6/10	8.8/10
Price per serving	$6.25	$1.67	$3.00	$0.33
Doses of Alpha BRAIN Black Label's ingredients
Mucuna Pruriens	1,000 mgvelvet bean seed extract standardized to 15% L-dopa (150 mg)No cognitive dose range	Not in formula	Not in formula	Not in formula
Citicoline	250 mgCognizin®At or above the study dose benchmark	250 mgCognizinAt or above the study dose benchmark	500 mgCognizinAt or above the study dose benchmark	Not in formula
L-Theanine	100 mgAt or above the study dose benchmark	100 mgAt or above the study dose benchmark	400 mgAt or above the study dose benchmark	200 mgL-theanineAt or above the study dose benchmark
Caffeine	25 mganhydrous15 mg below the study dose benchmark	100 mgPurCaf organic caffeine from green coffee beanAt or above the study dose benchmark	120 mgnatural caffeine, source not statedAt or above the study dose benchmark	100 mgcaffeine (anhydrous per the product page)At or above the study dose benchmark
Lutein + Zeaxanthin	24 mgLutemax® 2020 (20 mg lutein + 4 mg zeaxanthin isomers)At or above the study dose benchmark	Not in formula	Not in formula	Not in formula
Phosphatidylserine	200 mgSerinAid® (label lists 200 mg phosphatidylserine)100 mg below the study dose benchmark	140 mgSerinAid (200 mg at 70% phosphatidylserine)160 mg below the study dose benchmark	Not in formula	Not in formula
Huperzine A	0.2 mgHuperzia serrata whole extract 20 mg at 1% huperzine A0.2 mg below the study dose benchmark	0.3 mgHuperzia serrata leaf0.1 mg below the study dose benchmark	Not in formula	Not in formula
Lion's Mane Mushroom	500 mgmycelium and fruiting body, extract strength not stated1,300 mg below the study dose benchmark	Not in formula	Not in formula	Not in formula

The products that share the most cognitive ingredients with Alpha BRAIN Black Label are shown first. Any product sharing at least two can be added.

Transparent Labs Cognition is the closest match, with the same 250 mg of Cognizin and 100 mg of theanine, 140 mg of phosphatidylserine, a little huperzine A and 600 mg of rhodiola, for $1.67 a serving. It has 100 mg of caffeine instead of 25 mg, so it's the better pick if you want to feel something, and it leaves out the velvet bean and Lutemax.

If you'd rather skip caffeine, Mind Lab Pro shares Black Label's 250 mg of Cognizin, 100 mg of theanine and 500 mg of lion's mane for $2.30, and the original Alpha Brain costs $1.78, though most of its amounts are hidden. What Black Label's extra money really buys is the velvet bean and the Lutemax, and only the Lutemax has research at this amount.

Onnit sold the 80-capsule bottle for $124.95 when we checked. That's $6.25 a serving, and a bottle lasts 20 days if you take it daily.² That makes it one of the most expensive brain supplements we've audited. Onnit's subscription page says every subscription order is 15 percent off, and you can set deliveries anywhere from every 15 to every 90 days.³⁰

Onnit also sells Black Label through its own Amazon store, but its guarantee doesn't cover Amazon orders.³¹¹⁶

• onnit.com direct

  Listed price

  $124.95

  Per serving

  $6.25

  Status

  In stock (80 count, one-time)

• Amazon (official store)

  Price

  Check price on Amazon

  Status

  In stock, sold by ONNIT (New York 10001)

These are the seven ingredients with a research range, each priced on its own at the amount the studies started from. Velvet bean has none, so it isn't on the list.

The list has the cost a day for each, and buying them separately lets you take the lion's mane and phosphatidylserine at the amounts their studies used, which Black Label doesn't.

SOMA Analytics

Written review and video, one tester · Jason Mills, fact checked · Updated Aug 9, 2026

“it really works, and is worth giving a try.”

Full breakdown

WholisticResearch

Written review, three testers for six weeks · Jacob Kovacs, reviewed by Jason Williams, PhD · Sep 28, 2026

“While it is effective, it may be pricey and underdoses some of its ingredients.”

Full breakdown

Illuminate Labs

Written review, ingredient analysis · Taylor Graber MD and Calloway Cook, medically reviewed by DJ Mazzoni MS, RD · Updated Aug 30, 2025

“Overall, we do not currently recommend Alpha Brain Black Label.”

Full breakdown

Your Inception

Video, 30 days of use · Greg, on YouTube (46.8 thousand subscribers) · Jan 20, 2022

“personally, I prefer the original formula because I just got stronger effect”

Full breakdown

TheNootropicReviewer

Video review · Michael, on YouTube (88.5 thousand subscribers) · Aug 3, 2021

“this is a really solid product i would rate it seven out of ten”

Full breakdown

Most reviewers describe a mild effect, and several mention jitters even at 25 mg of caffeine. SOMA Analytics noticed "a heightened sense of focus" about 40 minutes after a dose, along with "mild jitters,"³² WholisticResearch rates it 3.6 out of 5 after a six-week test by three of its own staff,³³ and TheNootropicReviewer gives it 7 out of 10.³⁴ Your Inception felt nothing in the first week and prefers the original,³⁵ Innerbody says the customers it spoke to felt more focused on the original too,³⁶ and Illuminate Labs doesn't recommend Black Label at all.³⁷

Watch for formula mix-ups when you read around. WholisticResearch compares Black Label's citicoline with 100 mg in the original, which has none, Consumer Health Digest lists a 40-capsule bottle, and Wellness Digest still lists bacopa and alpha-GPC.³³³⁸³⁹

The L-dopa is the thing to know about. Each serving has 150 mg, the active compound in Parkinson's medicine, and the patient leaflet for levodopa asks you to tell your doctor about MAO inhibitors, a group that includes some antidepressants and the Parkinson's drug selegiline.⁴⁰ Citicoline's prescription label in Spain also warns that it interacts with levodopa,⁴¹ so if you take an antidepressant, a Parkinson's drug or any other medicine, check with your doctor before trying Black Label.

Don't take it alongside the original Alpha Brain either, as Onnit says.² A serving of each would give you 600 mcg of huperzine A in a day, an ingredient that slows the breakdown of acetylcholine and was studied in people with Alzheimer's.²⁸ Black Label also has 25 mg of caffeine, and Onnit says it isn't for anyone pregnant, breastfeeding or under 18. We're researchers, not doctors.

Black Label is the Alpha Brain you can actually check, with every dose on the label and three ingredients at the amounts their studies used. What it isn't is a proven focus formula, because its biggest ingredient, 1,000 mg of velvet bean, has no research behind it for focus, the caffeine is below the smallest amount we found tested, and we found no trial of Black Label itself.

If you want Cognizin, theanine and Lutemax in one bottle and the price doesn't put you off, make your first purchase of Black Label on onnit.com so the guarantee covers it. If you want a lift you'll notice, Transparent Labs Cognition costs far less a serving and has four times the caffeine. Either way, check with your doctor first if you take any medication.

44 sources cited

1. Alpha BRAIN Black Label supplement facts panel on the product page. 4 capsules a serving, 20 servings, velvet bean seed extract 1,000 mg at 15% L-dopa, lion's mane (mycelium and fruiting body) 500 mg, Cognizin citicoline 250 mg, phosphatidylserine (SerinAid) 200 mg, L-theanine 100 mg, caffeine anhydrous 25 mg, Huperzia serrata extract 20 mg (200 mcg huperzine A), lutein 20 mg and zeaxanthin isomers 4 mg (Lutemax 2020). Other ingredients are a vegetarian capsule, microcrystalline cellulose, L-leucine, maltodextrin, silica and sucrose. Accessed Oct 29, 2026. onnit.com (label image)
2. Onnit Labs. Alpha BRAIN Black Label (80 ct) product page. "break-glass-in-case-of-emergency, must-get-stuff-done NOW formula", "builds on the original formula", the velvet bean card ("a small, naturally occurring precursor to dopamine"), the comparison box ("80 Capsules", "Helps with blue light eye fatigue"), the "COA Tested" badge with no linked certificate, an ingredient list naming six ingredients without the lion's mane and caffeine, directions (4 capsules daily or as needed with a light meal, no more than 4 in 24 hours, skip if already taking the original), warnings, $124.95. Accessed Oct 29, 2026. onnit.com
3. Docherty S, et al. The acute and chronic effects of lion's mane mushroom supplementation on cognitive function, stress and mood in young adults. A double-blind, parallel groups, pilot study. Nutrients, 2023. 1.8 g a day for 28 days, 41 healthy adults aged 18 to 45, faster Stroop performance 60 minutes after a single dose. PMID 38004235
4. McGlade E, et al. Improved attentional performance following citicoline administration in healthy adult women. Food Nutr Sci, 2012. 250 or 500 mg a day of Cognizin for 28 days, 60 women aged 40 to 60. Two authors affiliated with Kyowa Hakko, which supplied the Cognizin. DOI 10.4236/fns.2012.36103
5. Kato-Kataoka A, et al. Soybean-derived phosphatidylserine improves memory function of the elderly Japanese subjects with memory complaints. J Clin Biochem Nutr, 2010. 100 or 300 mg a day for 6 months, 78 adults aged 50 to 69, scores rose in all groups including placebo, with gains against baseline confined to those with the lowest starting scores. PMID 21103034
6. Stringham NT, Holmes PV, Stringham JM. Effects of macular xanthophyll supplementation on brain-derived neurotrophic factor, pro-inflammatory cytokines, and cognitive performance. Physiol Behav, 2019. 13 or 27 mg a day of lutein and zeaxanthins for 6 months, 59 adults aged 18 to 25. Grant from OmniActive Health Technologies, Lutemax's maker. PMID 31425700
7. ClinicalTrials.gov search for Onnit. NCT02739139 (original Alpha Brain), NCT07495592 (original Alpha Brain and a two-capsule "Alpha Brain 2.0", completed Jun 26, 2026, no results posted), and unrelated Onnit products. No Black Label trial. Checked Oct 29, 2026. clinicaltrials.gov
8. PubMed search for "alpha brain black label" OR "onnit black label". No records. Checked Oct 29, 2026. pubmed.ncbi.nlm.nih.gov
9. Onnit Labs. Alpha BRAIN (original, 90 ct) supplement facts panel. Vitamin B6, Onnit Flow Blend (L-tyrosine, L-theanine, oat straw, phosphatidylserine), cat's claw, Onnit Focus Blend (alpha-GPC, bacopa, huperzine A 400 mcg), Onnit Fuel Blend (L-leucine, pterostilbene). Accessed Oct 29, 2026. onnit.com
10. Solomon TM, et al. A randomized, double-blind, placebo controlled, parallel group, efficacy study of Alpha BRAIN administered orally. Hum Psychopharmacol, 2016. The original Alpha Brain for 6 weeks, 63 adults aged 18 to 35, funded by Onnit. PMID 26876224
11. Nader. Alpha Brain Black Label review. FitFrek, modified Apr 22, 2026. Says Black Label "includes all the ingredients of Alpha Brain". Accessed Oct 29, 2026. fitfrek.com
12. Katzenschlager R, et al. Mucuna pruriens in Parkinson's disease. A double blind clinical and pharmacological study. J Neurol Neurosurg Psychiatry, 2004. Single doses of 15 g and 30 g of mucuna against 200/50 mg levodopa/carbidopa, 8 patients. PMID 15548480
13. Stringham JM, Stringham NT, O'Brien KJ. Macular carotenoid supplementation improves visual performance, sleep quality, and adverse physical symptoms in those with high screen time exposure. Foods, 2017. 24 mg a day of Lutemax 2020 for 6 months, 48 young adults with at least 6 hours of daily screen time. Funded by OmniActive Health Technologies, which supplied the capsules, and the lead author consults for it. PMID 28661438
14. Onnit Help Center. Product information, certifications and warnings (updated May 8, 2026). "We manufacture all of our products at NSF certified GMP facilities located in the United States. Within the FDA 21 CFR 111 regulations, we test every lot to meet product specification, label claims, and requirements for heavy metals and microbial contamination." Accessed Oct 29, 2026. help.onnit.com
15. NSF, Informed Choice and Informed Sport searches for Onnit. "No Matching Products Found" (NSF) and no results (Informed Choice, Informed Sport). Checked Oct 29, 2026. info.nsf.org
16. Onnit Help Center. 30 Day Money Back Guarantee (updated Sep 21, 2026). First-time purchase of any Onnit supplement, "no price limit", keep the product, request within 30 days of purchase with the order ID, product cost only with shipping not refunded, onnit.com orders only, Amazon excluded. Accessed Oct 29, 2026. help.onnit.com
17. Onnit Labs. Refund policy. Keep-It guarantee "Applies only to first-time purchases of select products under $40", unopened products returnable within 30 days at the buyer's cost. Undated. Accessed Oct 29, 2026. onnit.com/policies/refund-policy
18. Cilia R, et al. Mucuna pruriens in Parkinson disease. A double-blind, randomized, controlled, crossover study. Neurology, 2017. Single doses of roasted-seed powder at 12.5 and 17.5 mg/kg, 18 patients with advanced Parkinson's disease. PMID 28679598
19. PubMed search for "mucuna pruriens" with cognition, memory, attention, mood or focus in randomized or trial records. No records. Checked Oct 29, 2026. pubmed.ncbi.nlm.nih.gov
20. Lebedev AV, et al. Effects of daily L-dopa administration on learning and brain structure in older adults undergoing cognitive training. A randomised clinical trial. Sci Rep, 2020. 100/25 mg L-dopa/benserazide before each of 20 training sessions over 4 weeks, 63 healthy adults aged 65 to 75. The L-dopa group improved less in spatial intelligence than placebo. PMID 32251360
21. Mori K, et al. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment. A double-blind placebo-controlled clinical trial. Phytother Res, 2009. 3,000 mg a day of tablets made of 96% dried fruiting body powder, about 2,880 mg of powder, for 16 weeks, 30 adults aged 50 to 80. PMID 18844328
22. Evans C, et al. A pilot proof-of-concept study to evaluate the physiological and cognitive impacts of Hericium erinaceus on healthy adults. Nutrients, 2026. 2 g a day of mycelial biomass and fruiting body for 28 days, 10 healthy adults, no placebo group, no significant change in executive function or plasma BDNF. PMID 42884628
23. Nakazaki E, et al. Citicoline and memory function in healthy older adults. A randomized, double-blind, placebo-controlled clinical trial. J Nutr, 2021. 500 mg a day for 12 weeks, 100 adults aged 50 to 85, funded by Kyowa Hakko Bio. PMID 33978188
24. Crook TH, et al. Effects of phosphatidylserine in age-associated memory impairment. Neurology, 1991. 300 mg a day of bovine cortex phosphatidylserine for 12 weeks, 149 adults. PMID 2027477
25. Giesbrecht T, et al. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness. Nutr Neurosci, 2010. 97 mg theanine with 40 mg caffeine, single dose, 44 young adults, improved task-switching accuracy and alertness at 20 and 70 minutes. PMID 21040626
26. McLellan TM, Caldwell JA, Lieberman HR. A review of caffeine's effects on cognitive, physical and occupational performance. Neurosci Biobehav Rev, 2016. PMID 27612937
27. Lieberman HR, et al. The effects of low doses of caffeine on human performance and mood. Psychopharmacology (Berl), 1987. Single doses of 32, 64, 128 and 256 mg, 20 healthy men. As little as 32 mg improved auditory vigilance and visual reaction time. PMID 3114783
28. Rafii MS, et al. A phase II trial of huperzine A in mild to moderate Alzheimer disease. Neurology, 2011. 200 or 400 mcg twice a day for 16 weeks, 210 patients, no effect at 200 mcg twice a day. PMID 21502597
29. Yang G, et al. Huperzine A for Alzheimer's disease. A systematic review and meta-analysis of randomized clinical trials. PLoS One, 2013. 20 trials, rated low quality. PMID 24086396
30. Onnit. Subscription program FAQ. "Every subscription order receives a 15% discount off MSRP unless otherwise noted." Delivery intervals of 15 to 90 days offered on the Black Label product page. Accessed Oct 29, 2026. onnit.com
31. Amazon.com listing B095J9N224, ONNIT Alpha Brain Black Label, 80 count, ships from Amazon, sold by ONNIT. Checked Oct 21, 2026 with a New York delivery address. amazon.com
32. Mills J. Alpha Brain Black Label review. SOMA Analytics, updated Aug 9, 2026. Current formula, first-person use. soma-analytics.com
33. Kovacs J, Williams J (reviewer). Alpha Brain Black Label review. WholisticResearch, Sep 28, 2026. Overall rating 3.6 out of 5, a six-week test by three named staff. Compares Black Label's citicoline with "100mg in regular Alpha Brain". Accessed Oct 29, 2026. wholisticresearch.com
34. TheNootropicReviewer. Alpha Brain Black Label Review. My New Favorite? YouTube, Aug 3, 2021. Rated seven out of ten. youtube.com
35. Your Inception. Alpha Brain Black Label - My Unexpected 30 Day Experience. YouTube, Jan 20, 2022. 30 days of use, prefers the original formula. youtube.com
36. Anderson L. Alpha Brain review, section on other Alpha Brain products. Innerbody, last updated Jul 16, 2024. No score for Black Label. innerbody.com
37. Graber T, Cook C, Mazzoni DJ (medical reviewer). Alpha Brain review, Black Label section. Illuminate Labs, last updated Aug 30, 2025. Does not recommend Black Label. illuminatelabs.org
38. Alpha Brain Black Label review. Consumer Health Digest, reviewed by Olivia DiPio, RDN, LD, updated Apr 2, 2026. Overall rating 3.7, gives 40 capsules a bottle and $3.12 a serving. consumerhealthdigest.com
39. Alpha Brain Black Label reviews. Wellness Digest, reviewed by Dr. Sarah Brewer, last updated Mar 26, 2026. Lists bacopa, alpha-GPC and AC-11, which are in the original formula, not Black Label. wellnessdigest.com
40. MedlinePlus. Levodopa and carbidopa. Tell your doctor about MAO inhibitors such as phenelzine, selegiline or tranylcypromine taken now or in the past two weeks. Last revised Jun 15, 2026. Accessed Oct 21, 2026. medlineplus.gov
41. AEMPS (Spanish medicines agency). Somazina (citicoline) summary of product characteristics. Dosing 500 to 2,000 mg a day, and the levodopa interaction warning. Accessed Sep 18, 2026. CIMA FT 69416
42. Dassanayake TL, et al. Dose-response effect of L-theanine on psychomotor speed, sustained attention, and inhibitory control. A double-blind, placebo-controlled, crossover study. Nutr Neurosci, 2023. Single doses of 100, 200 or 400 mg, 32 young adults. PMID 36263942
43. Xu SS, et al. Efficacy of tablet huperzine-A on memory, cognition, and behavior in Alzheimer's disease. Zhongguo Yao Li Xue Bao, 1995. 0.2 mg twice a day for 8 weeks, 103 patients. PMID 8701750
44. Lopresti AL, Smith SJ, Drummond PD. The effects of lutein and zeaxanthin supplementation on cognitive function in adults with self-reported mild cognitive complaints. Front Nutr, 2022. 10 mg lutein and 2 mg zeaxanthin a day for 6 months, 90 adults aged 40 to 75. PMID 35252311