Ingredient Dossier · 5-Brain® Formula · nutropx.com/science
Acetyl-L-Carnitine
ALCAR — The Brain’s Mitochondrial Fuel Carrier
Acetyl-L-Carnitine (ALCAR) is a naturally occurring amino-acid derivative that crosses the blood–brain barrier more readily than plain L-carnitine. In the brain, it plays two well-characterized biochemical roles: supporting mitochondrial energy metabolism by facilitating fatty-acid transport for ATP production, and serving as an acetyl-group donor involved in the synthesis of acetylcholine — a neurotransmitter associated with memory and learning.
Crosses the blood–brain barrier
Mitochondrial energy metabolism
Acetylcholine precursor pathway
Endogenously produced
Clinically studied form
Carnitine isolated
1905
Gulewitsch & Krimberg
First clinical trials
1980s
Italian research groups
5-Brain® dose
500 mg
Per 3-capsule daily serving
Also obtained from
Diet
Red meat, dairy; synthesized endogenously
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What is it?
Acetyl-L-Carnitine is the acetylated ester of L-carnitine, a compound the body synthesizes from the amino acids lysine and methionine, primarily in the liver and kidneys. It is also obtained through dietary sources — particularly red meat and dairy products. What distinguishes ALCAR from plain L-carnitine is its ability to cross the blood–brain barrier efficiently, making it directly relevant to brain metabolism in a way that L-carnitine itself is not.
ALCAR has been present in scientific literature since the 1980s, when Italian research groups began investigating its role in neurological function. Its two primary brain-relevant biochemical roles — mitochondrial fatty-acid transport and acetyl-group donation for acetylcholine synthesis — are well-characterized at the mechanistic level. These mechanisms are the foundation for its inclusion in the 5-Brain® formula.
Important context for this page: The majority of ALCAR human clinical research has been conducted in older adults and other populations experiencing age-related cognitive changes or chronic fatigue conditions. There is no published randomized controlled trial of ALCAR alone in healthy adults specifically for cognitive function or energy. The evidence base described here is therefore primarily mechanistic (biochemical and preclinical), with clinical research from other populations included as scientific context. ALCAR in 5-Brain® is included based on its well-established biochemical mechanisms and its role as a complementary ingredient within a multi-ingredient formula.
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Research timeline
1905
L-carnitine isolated — Gulewitsch and Krimberg isolate carnitine from muscle extract. The compound’s role in biology is not yet understood.
1963
Mitochondrial transport role characterized — Fritz & Yue establish that carnitine is essential for shuttling long-chain fatty acids across the inner mitochondrial membrane for beta-oxidation — the core mechanism that defines carnitine’s role in energy metabolism.
1970s–80s
ALCAR’s CNS relevance identified — Italian research groups (Sigma-Tau Pharmaceuticals) identify that the acetylated form crosses the blood–brain barrier and donates acetyl groups for acetylcholine synthesis. First clinical investigations begin.
1989
Cholinergic mechanism confirmed in animal research — Imperato et al. demonstrate that systemic ALCAR dose-dependently increases acetylcholine release in rat striatum and hippocampus — a stereospecific, calcium-dependent effect consistent with physiological cholinergic activation.
1990s–2000s
Clinical trial era — Multiple double-blind RCTs were conducted in older adults and other populations experiencing age-related cognitive changes or chronic fatigue conditions. The Montgomery et al. 2003 meta-analysis (21 RCTs, n=1,204) synthesized the older-adult research base.
2002
Mitochondrial mechanism in aged brain — Liu, Hagen, Ames et al. (PNAS) demonstrate that ALCAR (with or without lipoic acid) partially restores mitochondrial function, reduces oxidative damage, and is associated with improved spatial memory in aged rats — a foundational preclinical paper for the mitochondrial aging narrative.
2017
Cochrane review in healthy adults — Chen et al. conduct the most rigorous systematic review of carnitine for cognitive enhancement in cognitively healthy people. Finding: only two eligible trials existed (both plain L-carnitine, not ALCAR) and neither demonstrated cognitive benefit. ALCAR-specific healthy-adult RCT data remains absent from the literature.
2018
Nasca et al. (PNAS) — observational biomarker study — Reports that plasma acetylcarnitine levels are lower in people with major depressive disorder vs healthy controls. This is an observational finding about naturally occurring levels — not a supplementation trial — and does not establish that taking ALCAR affects depression or mood.
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How it works — mechanisms of action
ALCAR’s biochemical roles in the brain are among the best-characterized of any ingredient in the 5-Brain® formula. The two core mechanisms — mitochondrial energy support and acetylcholine precursor activity — are established at the cellular and animal-model level. A third mechanism, involving neurotrophic signaling pathways, is supported by preclinical data only.
ALCAR’s dual mechanism — energy supply and neurotransmitter precursor
ALCAR is one of few cognitive ingredients with two well-characterized parallel mechanisms. The mitochondrial role (carnitine shuttle of long-chain fatty acids into the mitochondrial matrix) is established cellular biochemistry; the acetylcholine precursor role is supported primarily by preclinical evidence. Diagram is schematic.
ALCAR / cholinergic signaling
Mitochondrion
Synaptic terminal
Professor 5-Brain explains
Think of ALCAR as doing two jobs at once in your brain cells. Job one: it’s a fuel delivery system — it helps shuttle fatty acids into the mitochondria (your cells’ power plants) so they can be burned for energy. Job two: it’s an acetyl-group donor — meaning it can contribute the raw material needed to make acetylcholine, the neurotransmitter most associated with memory and learning. The fact that it crosses the blood–brain barrier more efficiently than plain L-carnitine is what makes the acetylated version specifically relevant to brain function.
Mitochondrial fatty-acid transport & ATP production
Carnitine esters shuttle long-chain fatty acids across the inner mitochondrial membrane for beta-oxidation and ATP synthesis. ALCAR also donates acetyl groups into the mitochondrial acetyl-CoA pool, supporting cellular energy production in neurons. In preclinical research, ALCAR has been studied for associations with improved mitochondrial energy status in cortical tissue.
Biochemical mechanism · Animal research support
Acetylcholine synthesis (acetyl-group donor)
ALCAR can serve as an acetyl-group source for the synthesis of acetylcholine via acetyl-CoA and choline acetyltransferase. Animal research (Imperato et al. 1989) demonstrated that systemic ALCAR dose-dependently increased acetylcholine release in the striatum and hippocampus — a stereospecific, calcium-dependent effect consistent with physiological cholinergic activation.
Animal research · Preclinical mechanism
Neurotrophic signaling pathways (preclinical only)
In rodent models, ALCAR has been studied for associations with BDNF (brain-derived neurotrophic factor) and related neuronal signaling pathways, including PI3K/AKT/BDNF/VGF (Wang et al. 2015) and mGlu2 receptor epigenetics (Nasca et al. 2013). No human study has demonstrated that ALCAR supplementation raises BDNF levels. This mechanism is preclinical only.
Animal research only — not established in humans
Antioxidant & membrane support
In aged-rat models, ALCAR (alone or with lipoic acid) has been studied for associations with reduced RNA/DNA oxidative damage and restored mitochondrial structure in brain tissue (Liu/Hagen/Ames et al. 2002, PNAS). These findings represent preclinical mechanism context for the broader neuroprotective narrative.
Animal research · Preclinical mechanism
Blood–brain barrier penetration
Unlike plain L-carnitine, ALCAR crosses the blood–brain barrier efficiently due to its acetyl group, which makes it more lipophilic. This is the pharmacological distinction that makes ALCAR specifically relevant to brain metabolism — and why it is selected over plain L-carnitine in neurological research contexts.
Well-established pharmacology
Mental fatigue (research context)
In a population with chronic fatigue syndrome, ALCAR was associated with greater reductions in mental fatigue vs propionyl-L-carnitine, with associations on a Stroop attention measure (Vermeulen & Scholte 2004). The dose was 2 g/day — 4× the 5-Brain® serving — and the population had a diagnosed condition, not healthy adults.
Research in diagnosed condition population
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5-Brain® system mapping
ALCAR’s 5-Brain® system associations are anchored in its biochemical mechanisms rather than in healthy-adult clinical trial outcomes. Mechanistic evidence is clearly labeled as such.
Brain Energy & Longevity
Primary biochemical role. Mitochondrial fatty-acid transport and ATP support are well-characterized cellular mechanisms. Preclinical research associates ALCAR with mitochondrial energy status in brain tissue.
Neural Communication
Studied as an acetyl-group donor in the acetylcholine synthesis pathway — a neurotransmitter central to memory and learning. Animal research supports this cholinergic mechanism.
Focus & Attention
In a population with chronic fatigue syndrome, ALCAR was associated with Stroop attention measures (Vermeulen & Scholte 2004). Context: diagnosed condition population, 4× the 5-Brain® serving.
Memory & Learning
Cholinergic mechanism is relevant to memory-related signaling. No healthy-adult human trial has studied ALCAR alone for memory outcomes.
Mood & Stress Resilience
Observational research (Nasca 2018) found lower naturally occurring acetylcarnitine levels in people with major depressive disorder, but no ALCAR supplementation was given. Not a supplementation finding.
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Research evidence — full context
Each study below is labeled by design type, population, and dose context. Where research was conducted in populations with diagnosed conditions or at doses different from the 5-Brain® serving, these contextual factors are clearly stated.
Chen et al. (2017) — Cochrane Database of Systematic Reviews
Systematic review of RCTs in cognitively healthy people · 2 eligible trials, n=418 · Plain L-carnitine (not ALCAR)
The most rigorous synthesis of carnitine for cognitive enhancement in healthy people. Researchers found only two eligible trials — both using plain L-carnitine (not ALCAR) — and concluded they “were unable to draw any conclusions about the efficacy or safety of L-carnitine for cognitive enhancement in healthy adults.” No ALCAR-alone healthy-adult RCT qualified for inclusion. Evidence rated very low quality.
Key takeawayThe most authoritative ALCAR evidence synthesis. Cochrane reviewers found insufficient evidence to recommend ALCAR for healthy adults — no high-quality RCTs exist in healthy populations. Crucial honest framing point: ALCAR healthy-adult cognitive evidence is essentially absent.
Montgomery, Thal & Amrein (2003) — International Clinical Psychopharmacology
21 RCTs pooled · n=1,204 adults with MCI or mild Alzheimer’s disease · ALCAR 1.5–3 g/day · 3–12 months
The largest ALCAR meta-analysis in the published literature. In this population of adults with diagnosed mild cognitive impairment or mild Alzheimer’s disease, ALCAR-treated participants had better scores than placebo on clinical and psychometric scales by the 3-month assessment. Population: older adults with diagnosed cognitive impairment — not healthy adults. Doses used (1.5–3 g/day) are 3–6× higher than the 5-Brain® serving. We include this trial for transparency about the broader ALCAR research base; its findings apply to the diagnosed-condition population studied at the doses used.
Key takeawayMild cognitive impairment (MCI) population at 1,500–3,000 mg/day. Reported associations with cognitive measures. Population is MCI (disease-adjacent); dose is 3–6× the 5-Brain® serving. Not direct evidence for healthy-adult claims at our dose.
Vermeulen & Scholte (2004) — Psychosomatic Medicine
n=90 chronic fatigue syndrome patients · ALCAR 2 g/day vs propionylcarnitine vs combination · 24 weeks · Open-label (not blinded)
In this population of adults with chronic fatigue syndrome, the ALCAR arm reported statistically significant associations with reduced mental fatigue (p=0.015) and with Stroop attention measures. Propionyl-L-carnitine was associated with general fatigue; the combination was less effective than either alone. The clearest available data distinguishing ALCAR’s associations from other carnitine forms. Population: adults with chronic fatigue syndrome. Open-label design (not placebo-blinded). Dose: 2 g/day — 4× the 5-Brain® serving.
Key takeawayChronic fatigue syndrome population at 2,000 mg/day. Reported associations with mental fatigue. Population is CFS (clinical); dose is 4× 5-Brain®. Mechanism-suggestive only for healthy-adult context.
Malaguarnera et al. (2008) — Archives of Gerontology and Geriatrics
n=96 adults >70 meeting fatigue criteria · ALCAR 4 g/day · Well tolerated · No adverse events or lab abnormalities
In this population of adults >70 meeting defined fatigue criteria, ALCAR was associated with reduced physical and mental fatigue and with cognitive/functional status measures compared to placebo. Well-tolerated at 4 g/day with no adverse events or laboratory abnormalities reported. Population: elderly with diagnosed fatigue. Dose: 4 g/day — 8× the 5-Brain® serving. Most directly useful as a safety and tolerability reference at extended-duration high doses.
Key takeawayCentenarians with fatigue at 2,000 mg/day. Reported associations with physical and mental fatigue. Population is 100+ years with frailty; dose is 4× 5-Brain®. Background context only.
Malaguarnera et al. (2007) — American Journal of Clinical Nutrition
n=66 centenarians with fatigue · Plain levocarnitine 2 g/day · NOT acetyl-L-carnitine
This study used plain L-carnitine (levocarnitine) — not acetyl-L-carnitine. It is frequently misattributed as ALCAR evidence in supplement marketing literature. The fatigue, muscle mass, MMSE, and cognitive activity findings reported in this centenarian population were obtained with a different molecule than the one in 5-Brain®, and we include it here specifically to flag the misattribution.
Key takeawaySubjects with hepatic encephalopathy. Reported cognitive associations. Population is liver-disease patients; not transferable to healthy adults. Cited only for mechanistic context.
Nasca et al. (2018) — PNAS
n=116 (45 healthy controls + 71 MDD patients) · No ALCAR administered · Plasma acetylcarnitine measured by mass spectrometry
Researchers measured naturally occurring plasma acetylcarnitine levels and found they were lower in patients with major depressive disorder than in healthy controls (p<0.0001, effect size 0.8). Lower levels correlated with greater symptom severity and earlier onset. No ALCAR was administered in this study — participants were not given a supplement. The finding describes an association between a naturally occurring biomarker level and a diagnosed condition; it does not demonstrate that taking ALCAR as a supplement affects mood or depression, and BDNF was not measured. We include it here for transparency about how this paper is sometimes mischaracterized in supplement marketing.
Key takeawayAnimal mechanism study. Demonstrated epigenetic mechanisms in stress resilience pathways. Preclinical only; provides biological plausibility but cannot support human outcome claims.
Liu, Head, Hagen, Ames et al. (2002) — PNAS
Aged rats · ALCAR ± R-α-lipoic acid dietary supplementation · Mitochondrial function & memory measures
In aged rats, dietary ALCAR (alone or with lipoic acid) was associated with partial restoration of mitochondrial structure, reduced RNA/DNA oxidative damage, and associations with improved spatial and temporal memory performance. The combination with lipoic acid tended to be most effective. Animal study only — provides mechanistic context for the mitochondrial narrative. Human applicability not established.
Key takeawayAged rats. Reported associations with mitochondrial function and cognitive markers. Animal mechanism evidence; provides biological foundation for the mitochondrial mechanism story.
Wang et al. (2015) — Neuroscience
Mouse model · ALCAR 5–100 mg/kg · Forced-swim test; chronic unpredictable mild stress
In mouse stress models, ALCAR was associated with PI3K/AKT/BDNF/VGF signaling pathway activation in the hippocampus and prefrontal cortex. Pathway blockade attenuated the effect. Animal study only. No human data demonstrate that ALCAR supplementation raises BDNF. This study cannot support any human BDNF claim. Cited as the preclinical basis for the neurotrophic mechanism only.
Key takeawayAnimal study. Reported associations with BDNF and learning measures. Preclinical only; supports the neurotrophic mechanism narrative without supporting human outcome claims.
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What the research actually says
Honest evidence summary
ALCAR is a molecule with a well-characterized biochemical profile and a substantial body of clinical research — but the two do not overlap in the way supplement marketing often implies. The mechanistic story is well-established; the healthy-adult human evidence story is essentially absent.
What studies consistently support
- ALCAR crosses the blood–brain barrier more efficiently than plain L-carnitine — established pharmacology.
- ALCAR participates in mitochondrial fatty-acid transport via the carnitine shuttle, supporting cellular energy metabolism (well-established cellular biochemistry).
- ALCAR can serve as an acetyl-group donor in pathways relevant to acetylcholine synthesis (preclinical mechanism evidence).
- In clinical populations (MCI, chronic fatigue, hepatic encephalopathy, age-related cognitive changes), researchers have reported associations with cognitive and fatigue measures at doses of 1,500–3,000 mg/day.
What remains uncertain
- Whether ALCAR produces cognitive effects in healthy adults at all. The Cochrane review (Chen 2017) found no qualifying ALCAR-alone RCTs in healthy populations and was unable to draw efficacy conclusions for cognitively normal people.
- Whether 5-Brain®’s 500 mg/day dose produces effects comparable to the 1,500–3,000 mg/day used in the clinical-population trials.
- How meaningful supplementation is for individuals with adequate baseline carnitine status (ALCAR is obtained from diet and synthesized endogenously).
- Whether the mitochondrial and cholinergic mechanisms translate to noticeable cognitive effects at any oral supplementation dose in healthy adults.
What to realistically expect
- ALCAR is positioned in 5-Brain® as a foundational metabolic contributor, not a standalone cognitive enhancer.
- The 500 mg dose supports the biochemical pathway contribution rather than replicating clinical trial outcomes — we don’t claim it does.
- The mechanistic story is real (mitochondrial energy + cholinergic precursor), but customers should not expect clinical-trial-magnitude effects from healthy-adult dietary supplementation.
- ALCAR’s value in 5-Brain® is its multi-mechanism contribution alongside Bacopa, Ginkgo, PS, Meriva, and Chocamine — a different angle of biochemical support than any other ingredient in the formula.
Professor 5-Brain — the honest take
ALCAR is a fascinating ingredient because the biochemistry is excellent and the human evidence is thin — and most supplement brands lean hard on the first while ignoring the second. Our position is straightforward: ALCAR earns its spot in 5-Brain® because it’s the only ingredient in the formula that meaningfully touches the mitochondrial energy pathway, and that’s a real biochemical axis worth covering in a multi-mechanism cognitive formula. We’re not telling you 500 mg will replicate a 1,500 mg trial outcome. We’re telling you ALCAR brings a dimension to the formula that no other 5-Brain® ingredient does.
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What we can say — compliant claims framework
All structure/function claims require the FDA disclaimer. The following tiers reflect the evidentiary strength of available data.
Tiered claims framework
Tier 1 — Strongest / safest (well-established biochemistry)
Acetyl-L-carnitine plays a role in cellular energy metabolism, including in brain cells, via its function in mitochondrial fatty-acid transport.
Acetyl-L-carnitine crosses the blood–brain barrier more readily than plain L-carnitine.
Acetyl-L-carnitine serves as an acetyl-group donor used in the synthesis of acetylcholine, a neurotransmitter involved in memory and learning.
Tier 2 — Acceptable with mechanistic framing
Acetyl-L-carnitine plays a role in cellular energy metabolism within a multi-ingredient formula, anchored on its established mitochondrial mechanism.
Acetyl-L-carnitine is studied for its role in supporting mitochondrial function in brain cells.
Tier 3 — Preclinical framing only (must be labeled)
In preclinical research, acetyl-L-carnitine has been studied for its associations with BDNF-related neuronal signaling pathways. This finding is from animal studies only.
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Why we selected this form
Formulation rationale
ALCAR, not plain L-carnitine. The distinction matters. Only the acetylated form crosses the blood–brain barrier efficiently and participates in the acetylcholine synthesis pathway. Plain L-carnitine does not directly support either of these brain-relevant mechanisms, which is why ALCAR specifically is the form used in neuroscience research and included in 5-Brain®.
Mitochondrial energy dimension. No other ingredient in the 5-Brain® formula directly addresses mitochondrial fatty-acid transport and ATP production in neurons. ALCAR fills this specific mechanistic dimension — contributing a cellular energy-metabolism layer that complements the circulation, membrane, and signaling mechanisms of the other ingredients.
Complementary to the cholinergic stack. Bacopa monnieri and Sharp-PS® Green are both studied for associations with cholinergic signaling. ALCAR’s role as an acetyl-group donor in acetylcholine synthesis means these three ingredients are mechanistically complementary — approaching the cholinergic pathway from different angles within the same formula.
Dose context. 5-Brain® delivers 500 mg/day ALCAR. Most positive clinical trials used 1,500–3,000 mg/day. ALCAR is also obtained from diet (particularly red meat and dairy) and produced endogenously, meaning the 5-Brain contribution adds to an existing baseline. We position ALCAR as a contributing ingredient within a multi-ingredient formula, not as a standalone therapeutic dose.
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Synergy within the 5-Brain® formula
ALCAR + Bacopa + Sharp-PS®
All three ingredients have studied associations with the cholinergic pathway — ALCAR as an acetyl-group donor, Bacopa for acetylcholinesterase inhibition associations, and Sharp-PS® for membrane-level neurotransmitter support. Three distinct mechanistic angles on the same system.
Cholinergic pathway — three angles
ALCAR + Meriva® Curcumin
Both ingredients have studied associations with mitochondrial function and antioxidant pathways in brain tissue. ALCAR addresses fatty-acid transport and ATP; Meriva addresses the inflammatory environment around neuronal mitochondria. Complementary metabolic and protective dimensions.
Mitochondrial + anti-inflammatory
ALCAR + Chocamine®
Chocamine® delivers theobromine for near-term alertness; ALCAR contributes to the underlying mitochondrial energy-metabolism infrastructure. One ingredient for the immediate signal, the other for the cellular energy substrate — different timescales within the same energy-support dimension.
Acute alertness + cellular energy
ALCAR + Ginkgo
Ginkgo is studied for cerebral circulation and vascular mechanisms; ALCAR is studied for intracellular mitochondrial energy. These operate at different levels — extracellular blood flow and intracellular energy production — representing complementary dimensions of brain energy support.
Vascular + intracellular energy
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Dosage & context
5-Brain® dose
500 mg
per day · per 3-capsule serving · as acetyl-L-carnitine
Most positive clinical trials used 1,500–3,000 mg/day — the 5-Brain serving is a lower, foundational dose within a multi-ingredient formula, not a standalone clinical dose
ALCAR is also obtained from dietary sources (red meat, dairy) and synthesized endogenously — the supplement dose adds to an existing baseline that varies by diet
No specific timing requirement is established in the literature; take as part of the daily 5-Brain® serving
Discontinue at least 2 weeks before scheduled surgery — per DaVinci Laboratories guidance for the 5-Brain formula
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Safety & tolerability
TMAO note: Carnitine is metabolized by gut bacteria to trimethylamine (TMA), which the liver converts to trimethylamine-N-oxide (TMAO). TMAO has been associated with cardiovascular risk in observational research (Koeth et al. 2013, Nature Medicine). The cardiovascular relevance of supplemental carnitine-derived TMAO in healthy people is an active area of scientific discussion and is not settled. We disclose this transparently.
General tolerability
- Well tolerated in trials at doses up to 4 g/day (Malaguarnera 2008 — no adverse events or lab abnormalities)
- Long history of clinical use in neurological and metabolic research contexts
- Most common mild effects: GI upset (nausea, cramping) and, at high doses, fishy body odor from trimethylamine
Notes & cautions
- Possible agitation, restlessness, or insomnia at higher doses
- Theoretical interaction with thyroid hormone: L-carnitine acts as a peripheral antagonist of thyroid hormone action — consult your healthcare provider if on thyroid medication
- Possible interaction with anticoagulants (warfarin/acenocoumarol) — consult your provider if on blood thinners
- Caution in seizure disorders — discuss with your healthcare provider
- Not for use in pregnancy or breastfeeding without medical consultation
- Discontinue at least 2 weeks before scheduled surgery
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Frequently asked questions
What is the difference between ALCAR and plain L-carnitine?
Acetyl-L-carnitine (ALCAR) is the acetylated ester of L-carnitine. The key distinction is that ALCAR crosses the blood–brain barrier more efficiently due to its acetyl group, making it directly relevant to brain metabolism. Plain L-carnitine does not cross the blood–brain barrier readily and is not associated with the acetylcholine synthesis mechanism that ALCAR is. They are not interchangeable for brain-relevant applications, which is why the research and the 5-Brain® formula specify ALCAR specifically.
Are there clinical trials of ALCAR in healthy adults?
The most comprehensive review (Chen et al. 2017, Cochrane) found no qualifying randomized controlled trials of ALCAR alone in cognitively healthy adults for cognitive outcomes. The large majority of ALCAR human research has been conducted in older adults and other populations experiencing age-related cognitive changes or chronic fatigue conditions. This is why the 5-Brain® science page is transparent about the mechanistic basis for ALCAR’s inclusion rather than citing clinical outcome data in healthy people.
Does ALCAR raise BDNF?
In preclinical (animal) research, ALCAR has been studied for associations with BDNF-related neuronal signaling pathways (Wang et al. 2015). However, no human study has demonstrated that taking ALCAR as a supplement raises BDNF levels. The Nasca 2018 PNAS paper, sometimes cited in this context, was an observational study measuring naturally occurring plasma acetylcarnitine in people with depression — it did not administer ALCAR and did not measure human BDNF. We do not make a human BDNF claim for ALCAR.
Why is the dose in 5-Brain® lower than clinical trial doses?
Most positive ALCAR clinical trials used 1,500–3,000 mg/day. 5-Brain® delivers 500 mg/day as part of a multi-ingredient formula. ALCAR is also obtained from diet (particularly red meat and dairy) and produced endogenously by the body, so the supplement dose adds to an existing baseline. The 5-Brain® formula is designed as a complementary system across multiple ingredients and mechanisms — ALCAR contributes its mitochondrial and cholinergic dimensions within that context, not as a standalone clinical dose.
Can I take ALCAR with other medications?
ALCAR has a possible interaction with anticoagulant medications (warfarin, acenocoumarol) and may theoretically affect thyroid hormone action at high doses. If you are taking thyroid medication, anticoagulants, or have a seizure disorder, consult your healthcare provider before taking 5-Brain®. Discontinue at least 2 weeks before any planned surgical procedure.
References
Chen N et al. (2017) Cochrane Database Syst Rev Issue 3 Art CD009374 · PMID 28349514 · Montgomery SA, Thal LJ, Amrein R (2003) Int Clin Psychopharmacol 18(2):61–71 · PMID 12598816 · Malaguarnera M et al. (2008) Arch Gerontol Geriatr 46(2):181–90 · PMID 17658628 · Malaguarnera M et al. (2007) Am J Clin Nutr 86(6):1738–44 · PMID 18065594 (plain L-carnitine — not ALCAR) · Vermeulen RCW, Scholte HR (2004) Psychosom Med 66(2):276–82 · PMID 15039515 · Nasca C et al. (2018) PNAS 115(34):8627–32 · PMID 30061399 · Wang W et al. (2015) Neuroscience 285:281–91 · PMID 25463525 · Liu J et al. (2002) PNAS 99(4):2356–61 · PMID 11854529 · Imperato A, Ramacci MT, Angelucci L (1989) Neurosci Lett 107(1–3):251–5 · PMID 2616037 · Koeth RA et al. (2013) Nat Med 19(5):576–85 (TMAO context)
Chen N et al. (2017) Cochrane Database Syst Rev Issue 3 Art CD009374 · PMID 28349514 · Montgomery SA, Thal LJ, Amrein R (2003) Int Clin Psychopharmacol 18(2):61–71 · PMID 12598816 · Malaguarnera M et al. (2008) Arch Gerontol Geriatr 46(2):181–90 · PMID 17658628 · Malaguarnera M et al. (2007) Am J Clin Nutr 86(6):1738–44 · PMID 18065594 (plain L-carnitine — not ALCAR) · Vermeulen RCW, Scholte HR (2004) Psychosom Med 66(2):276–82 · PMID 15039515 · Nasca C et al. (2018) PNAS 115(34):8627–32 · PMID 30061399 · Wang W et al. (2015) Neuroscience 285:281–91 · PMID 25463525 · Liu J et al. (2002) PNAS 99(4):2356–61 · PMID 11854529 · Imperato A, Ramacci MT, Angelucci L (1989) Neurosci Lett 107(1–3):251–5 · PMID 2616037 · Koeth RA et al. (2013) Nat Med 19(5):576–85 (TMAO context)
This page is for educational and informational purposes only. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before beginning any supplement regimen, particularly if you are pregnant, nursing, taking medications (including anticoagulants or thyroid medications), have a seizure disorder, or have a medical condition. Discontinue use at least 2 weeks before surgery.