There is preliminary evidence that certain supplements modestly improve various aspects of memory or cognition. These benefits include boosting memory in people who do not have memory problems as well as improving memory or cognition in people with age-related cognitive decline, Alzheimer’s disease, and other forms of dementia. The supplements include B vitamins, choline, cocoa flavanols, curcumin, fish oil, ginkgo, huperzine A, iron, magnesium, and lutein and zeaxanthin.
In addition, certain foods, diets, and lifestyle changes have been associated with improvements in cognition or a decreased risk of dementia.
Use the links below for more details, including clinical evidence and dosage, for each supplement, as well as ConsumerLab's tests, reviews, and Top Picks for each type of supplement.
In Healthy Adults & Adolescents
Bacopa (Bacopa monnieri) is an herb which several small trials suggest may have very modest benefits in healthy adults without memory or cognitive deficits.
Choline supplements may help improve short-term memory and attention in healthy older adults, but this benefit has only been found with certain forms of choline, and not others.
Cocoa flavanols may have short-term cognitive benefits in healthy adults, such as improving attention, increasing processing speed and reducing mental fatigue.
Curcumin (from turmeric) may modestly improve some aspects of memory and cognition in healthy adults, but the benefit appears to be limited to several hours after use.
Ginkgo biloba may have some slight, short-term cognitive benefit in healthy adults, but be aware that studies have generally been company-funded, and not all studies have found a benefit.
Fish oil and omega-3 fatty acid supplements may slightly improve certain measures of memory and cognition in healthy adults who do not regularly consume fish and those with very low blood levels of DHA, although not all studies have found a benefit.
Iron supplementation to correct iron deficiency has been shown to improve verbal learning and memory in adolescent girls.
Ketones (also called ketone bodies) are molecules produced in the liver from fatty acids and can be used in the body and in the brain for energy when glucose (i.e., sugar) is not available. One small study found that a ketone-containing drink modestly increased cerebral blood flow and improved scores on one test of motor speed and visual attention in obese adults, but larger, long-term studies are needed to prove a benefit.
Lutein and zeaxanthin are carotenoids with antioxidant properties that are often included in vision health supplements, but there is preliminary evidence that these antioxidants may also improve brain functions such as visual processing, speed of processing, attention and memory, as well as reduce computer and screen-related headaches and eye strain.
Magnesium from foods and/or supplements may improve cognition in healthy older adults who consume much higher amounts of calcium than magnesium. Getting enough magnesium -- but not too much -- has also been associated with a decreased risk of developing mild cognitive impairment or dementia.
Cranberry supplementation has been proposed to help with memory and cognition due to its potential anti-inflammatory and antioxidant effects, but a study among healthy older adults showed very little improvement.
Inositol-stabilized arginine silicate, also called arginine silicate inositol or ASI (available as the branded ingredient Nitrosigine), is considered to be a more bioavailable source of arginine which may help to improve blood flow. However, a study showed very little cognitive benefit in young adults who supplemented with ASI.
For Age-related Cognitive Decline
Age-related cognitive decline is not considered a disease but a more gradual and, perhaps, normal consequence of aging. Below are supplements that may have modest benefit in older adults or in people with age-related cognitive decline.
B vitamins including B-6, B-12, and folic acid, taken alone and/or in combination, long-term, may help slow declines in memory and cognition in older adults with mild cognitive impairment.
Fish oil supplements may modestly improve some measures of cognition in adults with age-related cognitive decline, but the evidence is mixed and may depend on the level of cognitive function prior to treatment, age, diabetes status, and whether or not fish is already being consuming fish in the diet.
Spermidine is a naturally occurring compound produced in our bodies and found in a variety of foods. It plays an important role in cell maintenance and the clearance of damaged or abnormal cells and may also have anti-inflammatory effects.
Higher dietary intakes of spermidine have been associated with lower incidence of cognitive impairment in people (Schroeder, Cell Rep 2021). However, in a clinical trial among 100 men and women (average age 69) with subjective age-related cognitive decline, spermidine (0.9 mg of spermidine in 750 mg of wheat germ extract) for one year did not improve memory performance compared to placebo.The researchers also noted that the daily dose of spermidine used in the study was quite low (representing just a little less than 10% of the average daily dietary intake of 10 mg). [The low dose was chosen, in part, due to concerns from animal and laboratory studies, that compounds like spermidine (polyamines) may promote tumor growth in cancers such as breast, colon, lung, prostate and skin cancer (Nowotarski, Expert Rev Mol Med 2013)]. Interestingly, a greater number of participants who took spermidine reported musculoskeletal and connective tissue adverse effects during the course of the study compared to those taking the placebo (11 participants vs 4 in the placebo group), although the difference was not statistically significant (Schwarz, JAMA Netw Open 2022).
For Mild Cognitive Impairment (MCI)
Acetyl-L-carnitine supplementation may have some benefit in people with mild cognitive impairment.
B vitamins including B-6, B-12, and folic acid, taken alone and/or in combination long-term, may help slow declines in memory and cognition in older adults with mild cognitive impairment.
Fish oil supplements high in DHA may help reduce further cognitive decline among people with MCI, but possibly only among those with low blood levels of omega-3 fatty acids prior to treatment but not those with higher IQ prior to treatment. There is also evidence that having adequate B vitamin status may be needed to benefit from fish oil supplementation.
L-arginine supplementation may slightly improve cognitive function among some elderly individuals with mild cognitive impairment. Arginine can increase blood levels of nitric oxide, a compound that helps relax blood vessels and increase blood flow to various parts of the body. It may also help improve the function of mitochondria, the component of cells involved in energy production. Mitochondrial dysfunction has been linked with frailty and cognitive decline.
Medium chain triglycerides (MTC), occur naturally in coconut oil, can be converted by the liver into ketones, which, as discussed above, can be used by the brain as an alternative source of energy when glucose levels are low. Although one study in older adults with mild cognitive impairment found that a drink containing MCT oil significantly increased ketone uptake in the brain, participants had only slight improvements in episodic memory and executive function, but not in other measures of cognitive function.
Probiotics may modestly improve cognition in older adults with cognitive impairment.
CoQ10 supplementation may improve the reactivity of blood vessels to the brain (which could potentially improve blood flow to the brain) in people with MCI, according to one study, but it did not lead to improvement in memory or cognitive function.
Alzheimer's Disease & Dementia
Acetyl-L-carnitine supplementation may have benefit in the early (mild) stages of Alzheimer’s disease.
Choline supplementation may improve cognition in people with mild to moderate Alzheimer's disease, but this benefit has only been found with certain forms of choline.
Fish oil supplementation may modestly improve cognitive performance in people with mild to moderate Alzheimer’s disease, but there may only be benefit in people with adequate B vitamin status.
Huperzine A has been shown to improve memory, thinking, and behavioral function in people with Alzheimer's disease, multi-infarct dementia, and senile dementia. It may also enhance the effects of medications such as may enhance the effects of prescription drugs donepezil (Aricept) or tacrine (Cognex).
Possibly helpful, but no human studies:
Magnolia bark extract contains magnolol, honokiol, and other components that have been shown in laboratory studies to prevent the breakdown and increase levels of acetylcholine, a neurotransmitter that is essential for proper brain function, and to reduce the accumulation and neurotoxicity of amyloid proteins associated with Alzheimer's disease. Magnolia bark extracts and magnolol have been shown to lessen learning and memory impairments in mouse models of Alzheimer's disease, with the benefits of magnolol similar to that of donepezil, a prescription medication used for Alzheimer's disease (Lee, Biomol Ther (Seoul) 2012; Xian, Oxid Med Cell Longev 2020). However, it is not known if magnolia bark extract or its components are beneficial in preventing or treating Alzheimer's disease in humans, as no clinical trials have been reported.
Ginkgo biloba is often promoted to help treat dementias, including Alzheimer’s disease, but overall, there is no strong evidence from clinical trials showing a benefit.
Cautions and Concerns with Supplements
Be aware that some proprietary formulas that contain some of these ingredients, such as Procera AVH, may promise more of a benefit than clinical evidence suggests. The FDA has warned that many supplements promoted to treat Alzheimer's disease and dementia are marketed with unproven claims and are "selling false hope." The FDA has also advised consumers to avoid supplements promoted to prevent or treat traumatic brain injuries. Vinpocetine, an ingredient in memory supplements such as Procera AVH and Alpha Brain, may cause fetal harm or miscarriage, and should not be taken by women who are pregnant or who could become pregnant. It can also inhibit blood platelets from forming clots and could dangerously interact with other blood- thinning supplements like garlic, ginkgo and high dose vitamin E, and drugs such as aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), or pentoxifylline (Trental) and Coumadin.
Also be aware that some supplements promoted for memory and cognition contain drugs not approved by the FDA and not permitted to be sold as dietary supplement ingredients. These drugs include Noopept (omberacetam) and its analogs, such as piracetam, aniracetam, oxiracetam or phenylpiracetam.
Note that some experts have recommended that people at risk for Alzheimer's disease avoid copper-containing supplements due to possible contribution to cognitive decline. However, the evidence of this is limited and mixed. For details, see the Copper section of our Multivitamins Review.
Diet and Lifestyle for Memory:
Diets providing higher intakes of certain antioxidant compounds have been associated with a decreased risk of Alzheimer's disease and other forms of dementia. In a study that followed over 2,500 people 50 years of age or older for 20 years, the risk of Alzheimer's and other dementias was reduced by 76% among those with higher intakes of anthocyanins (16 mg/day from foods such as blueberries, strawberries and red wine) and by 46% among those with higher intakes of flavonols (14 mg/day from foods such as tea, apples and pears) compared to those with the lowest intakes (Shishtar, Am J Clin Nutr 2020). These higher amounts are not difficult to obtain. For example, you can get 16 mg of anthocyanins from just ¼ cup of blueberries (Routray, Compr Rev Food Sci Food Saf 2011).
When combined with other healthy lifestyle factors, consuming a high-quality "MIND diet" (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay) has been associated with a significantly decreased risk of Alzheimer dementia, according to results of two studies that followed over 2,500 older Americans for about six years. The MIND diet is based on ten healthy food groups (leafy green vegetables, other vegetables, nuts, berries, beans, whole grains, fish, poultry, olive oil, and wine) and five unhealthy food groups (red meats, butter and stick margarine, cheese, pastries and sweets, fried food, and fast food). The quality of the diet is evaluated by how often foods in each group are consumed. Five healthy lifestyle factors were considered: having the highest MIND diet score (upper 40%), not smoking, engaging in >150 minutes per week of moderate to vigorous-intensity physical activity, light to moderate alcohol consumption (one drink per day for women and two for men), and engagement in late-life cognitive activities (such as reading, writing, or playing chess). The risk of Alzheimer dementia was 37% lower in those with 2 to 3 healthy lifestyle factors and 60% lower in those with 4 to 5 factors compared to those with no or only one healthy lifestyle factor (Dhana, Neurology 2020).
A Mediterranean diet was also associated with benefits in a study in Italy among 1,902 adults 80 years or older. Those who reported most closely following a Mediterranean diet in the previous year were 34% less likely to have dementia than those who did not closely follow a Mediterranean diet, even after adjusting for other risk factors such as physical activity, alcohol intake and high blood pressure. Greater consumption of eggs, fruits and vegetables, carbohydrates, legumes (beans, lentils, peas, etc.) and greater food intake overall were also associated with a lower prevalence of dementia (Nicoli, Clin Nutr 2021).
A small study among 37 healthy older men and women (ages 65 to 70) found that those who drank 12 grams of freeze-dried strawberry powder mixed in water with breakfast and dinner (24 grams of powder daily, equivalent to 2 cups of fresh strawberries) for three months had modest improvements in two of several measures of cognition (word recognition and spatial navigation) compared to placebo. There were no improvements in attention, task switching, verbal working memory, or mood. The researchers had also expected improvements in gait and balance, but they did not occur. The study was funded by the U.S. Department of Agriculture and California Strawberry Commission (Miller, Br J Nutr 2021).