MemoHoney Ingredients: the six names, and what they actually are

Arginine is the direct precursor of nitric oxide, the signalling molecule that relaxes the lining of blood vessels. It is also the ingredient with the most awkward pharmacology on this list, because swallowing it is the least efficient way to raise it. Enzymes in the gut wall and the liver dismantle a large fraction of an oral dose before it reaches the circulation, which is why the head-to-head trial found citrulline at three grams twice a day raised trough plasma arginine further than arginine itself.

The clinical literature is substantial and its results are conditional. A meta-analysis of the endothelial trials found short-term oral arginine improved flow-mediated dilation, but essentially only in people whose baseline dilation was already poor; where vessel function was normal, the effect was not there to find. A later systematic review in cardiovascular and metabolic disease reached a similar conditional place, and an umbrella review of the meta-analyses summarised the field as useful in specific populations rather than generally.

Two things belong beside that. The first is the one memory result: a 2026 pilot randomised thirty-eight older adults with cognitive impairment to 6.4 grams a day of oral L-arginine or placebo for thirty days, and reported improvements in attention, memory and language. It is a pilot, it is small, and its dose is measured in grams. The second is VINTAGE MI, which gave three grams three times daily to patients after a heart attack and was stopped early. That trial is the reason this desk does not describe arginine as harmless at any amount, even though a capsule cannot approach nine grams.

Arginine bound to alpha-ketoglutarate, in a two-to-one ratio. It is a sports-nutrition ingredient with a short and unflattering research record, and it is the clearest single sign of which shelf this formula was assembled from.

The pharmacokinetic and performance trial gave four grams three times a day, twelve grams daily, to trained men for eight weeks. A seven-day study used the same twelve grams and measured blood flow, plasma arginine, nitric oxide metabolites and asymmetric dimethylarginine after resistance exercise. Both are dosed in the same place, and that place is a scoop rather than a capsule.

An acute trial gave a single three-gram dose to resistance-trained and untrained men forty-five minutes before exercise and found no improvement in muscular performance. Three grams is already several times more than a capsule can carry alongside five other ingredients, and it did nothing measurable in that setting. No trial of arginine AKG has measured memory in anybody.

Citrulline is the ingredient with the strongest human evidence on this list, and the evidence is cardiovascular. The kidney converts citrulline into arginine, which is why it raises arginine better than arginine does, and it is the reason this compound displaced arginine in most modern pre-workout formulas.

The blood-pressure meta-analysis pooled randomised trials using three to nine grams a day. Diastolic pressure fell, and the subgroup analysis is the part worth carrying away: the reduction appeared only in the arms dosing at six grams a day or more. A 2025 review of citrulline and watermelon intake in middle-aged and older adults looked at the same question in the age group this product is marketed to.

Closest to the brain, a 2025 trial gave taekwondo athletes 8.8 grams of L-citrulline a day for five consecutive days and measured cerebrovascular function during sprint interval training. It measured flow, not recall. A crossover study gave six grams of citrulline, or six grams of arginine, alongside 520 mg of nitrate, and looked at peripheral and central fatigue during knee extensions. Every one of those numbers is a gram figure.

The endurance form: citrulline bound to malic acid, which is itself an intermediate in energy metabolism. It is the version used in most exercise research, and a three-level meta-analysis published in 2026 pooled that literature for performance outcomes.

The trial most relevant to the people this product is aimed at is a pilot in physically active older women: twenty women aged 60 to 75 took three grams a day for six weeks alongside three exercise sessions a week, and lower-limb function improved. Three grams a day is the lowest daily figure anywhere in this reference set, and it is still several times a capsule.

A combined trial of arginine and citrulline malate together dosed by body weight: 0.15 grams per kilogram of arginine and 0.1 grams per kilogram of citrulline malate. For an eighty-kilogram adult that is twelve grams and eight grams. The relevance to this label is that the combination of arginine and citrulline malate has been studied, and it was studied at twenty grams a day between them.

The one essential nutrient in the formula, and the one where a missing number matters most. Niacin has a defined requirement, a defined upper limit and a well-known side effect, and without a printed figure a buyer can total up none of the three.

The Institute of Medicine reference intakes set the adult tolerable upper intake level at 35 mg a day of nicotinic acid from supplements, a figure driven by the flush rather than by organ damage. Above that, the picture changes by scale rather than by kind: the HPS2-THRIVE trial gave 2,000 mg a day with laropiprant to 25,673 patients and recorded serious adverse effects, and a published case report describes hepatotoxicity after large self-administered doses. The FDA Mini-Sentinel assessment reviewed prescription niacin safety across a national database.

Its cognition evidence points the other way and is observational. The Chicago Health and Aging Project found higher dietary niacin associated with a lower rate of incident Alzheimer’s disease and slower cognitive decline; the CARDIA cohort looked at niacin, folate, B6 and B12 intake through young adulthood against cognitive function in midlife. Both studied food. Neither tested a capsule.

Beta-alanine raises carnosine inside muscle, where carnosine buffers the acid produced by hard effort. It is the reason a scoop of pre-workout makes the face tingle, and it is the ingredient on this list with the least obvious reason to be in a memory capsule.

The International Society of Sports Nutrition position stand sets the working protocol at four to six grams a day for at least four weeks, names paraesthesia as the only reported side effect, and notes that dividing the dose or using a sustained-release form blunts it. A dosing comparison found a sustained-release twelve grams a day raised muscle carnosine faster while reducing the tingle, and a systematic risk assessment pooled the safety data across the literature.

There is a cognitive thread, and it is worth reading carefully because it is thinner than it first looks. One trial gave twelve grams a day for fourteen days before simulated military operational stress and measured cognition, mood and BDNF; a companion study did the same across a 24-hour operation. An imaging trial in twenty 60- to 80-year-olds used 2.4 grams a day and reported changes in fractional anisotropy in the hippocampus and amygdala, which is a measure of white-matter structure rather than of remembering anything. A meta-analysis of histidine-containing dipeptides found an improvement in delayed recall, and the NEAT trial gave carnosine itself at two grams a day for up to twelve weeks and found cognitive improvement in its younger participants.