Older adults with mild cognitive impairment linked to Alzheimer’s disease performed better on several memory measures after taking a specialized turmeric extract for four months, although researchers cautioned that the small, uncontrolled study cannot establish that the supplement caused the improvements.
By yourNEWS Media Newsroom.
A concentrated turmeric extract containing compounds other than the spice’s better-known curcumin was associated with improvements in working memory and several other cognitive measures among a small group of older adults with early Alzheimer’s-related impairment, according to newly published research from Japan.
The study published in Frontiers in Nutrition followed patients with mild cognitive impairment due to Alzheimer’s disease who took a Curcuma longa extract for four months while waiting to begin anti-amyloid antibody treatment. Researchers enrolled 13 participants, but three were excluded from the final analysis because of inadequate supplement intake or invalid data, leaving 10 people whose results were evaluated.
The findings were encouraging on several measures but remain preliminary. The study had no placebo or untreated comparison group, lasted only four months and included just two men and eight women. Participants had an average age of 74.8.
Researchers specifically examined a turmeric extract standardized to three compounds — turmeronol A, turmeronol B and bisacurone — rather than focusing primarily on curcumin, which has received considerably more attention in previous turmeric research.
Participants took two capsules each day containing a combined 0.96 grams of the turmeric extract preparation. The daily amount supplied 100 micrograms of turmeronol A, 100 micrograms of turmeronol B and 400 micrograms of bisacurone.
After four months, participants’ average score on a digital measure combining visual learning and working memory increased from 90 to 97.4. Researchers reported that the difference was statistically significant.
Another digital measure produced an estimated “brain age” based on performance relative to age-based reference data. The group’s average estimated brain age fell from 79.5 years at the beginning of the study to 76.3 after four months.
The authors cautioned, however, that this measure should not be interpreted as evidence that participants’ brains biologically became younger by more than three years. The test generates an age-based estimate from cognitive performance, and its reference database was not specifically validated for people with mild cognitive impairment.
Other measures produced a more complicated picture.
Scores in the attention portion of the Japanese version of the Montreal Cognitive Assessment improved, as did performance on a digit-span task involving the ability to remember and repeat sequences of numbers. Those findings may point to changes in functions involving working memory and attention, the researchers wrote.
Yet the total Montreal Cognitive Assessment score did not significantly improve. A separate composite measuring concentration, psychomotor performance and attention also showed no significant change, and researchers found no significant improvement in several other measurements of cognitive processing.
The blood testing provided another reason for caution. Investigators found no significant changes in high-sensitivity C-reactive protein, tumor necrosis factor-alpha or brain-derived neurotrophic factor, markers examined because inflammation and neuronal function have been proposed as possible mechanisms through which turmeric compounds might affect cognition.
The researchers therefore could not establish a biological explanation for the cognitive changes.
Previous laboratory and animal research has suggested that turmeronols and bisacurone may have anti-inflammatory activity. Turmeronols have been studied for their potential effects on inflammatory signaling in microglial cells, which are immune cells in the central nervous system, while bisacurone has also demonstrated anti-inflammatory properties in preclinical research.
Those findings were among the reasons investigators chose the compounds for further study. The new trial, however, did not demonstrate that reducing inflammation was responsible for the participants’ cognitive results.
The study’s design also makes it impossible to rule out other explanations.
Repeated exposure to cognitive testing can sometimes improve scores because participants become more familiar with the tasks, a phenomenon known as a practice effect. Researchers attempted to reduce that problem by using randomized card sequences in the digital tests, but acknowledged that practice effects could not be fully excluded.
“Further investigation in larger, placebo-controlled studies is warranted to evaluate the effects of different doses and durations of CLE intake,” the study authors wrote.
Funding represents another important consideration. House Wellness Foods Corp., the Japanese company that supplied the turmeric preparation, financed the research and provided the capsules. According to the paper, the company was not involved in the study design, data analysis, interpretation, manuscript preparation or decision to publish.
The study therefore provides an early signal rather than evidence that turmeric extract treats or slows Alzheimer’s disease.
That distinction is particularly important because the participants had mild cognitive impairment attributed to Alzheimer’s disease, a stage in which patients have measurable cognitive problems but generally retain more independence than people with later dementia.
The findings also differ from a separate 2026 randomized, double-blind, placebo-controlled turmeric extract trial involving healthy adults ages 40 to 69 who had subtle cognitive weaknesses but did not have Alzheimer’s-related mild cognitive impairment. In that trial, researchers reported improvements in some measures of orientation and attention after 24 weeks, but not across the full range of cognitive endpoints that were tested.
Earlier research has also examined curcumin itself. One widely discussed randomized UCLA study involving a bioavailable curcumin formulation reported improvement in certain memory measures over 18 months compared with placebo. Those findings involved a different turmeric compound, population and treatment protocol and cannot be directly applied to the extract evaluated in the new Japanese study.
The latest research comes as treatment for early Alzheimer’s disease is being transformed by anti-amyloid antibodies such as Leqembi, or lecanemab, and Kisunla, or donanemab.
Those prescription therapies have demonstrated an ability to slow cognitive and functional decline in selected patients with early symptomatic Alzheimer’s disease, but they do not cure or reverse the disease.
They also require significant medical monitoring because of amyloid-related imaging abnormalities, known as ARIA.
The FDA prescribing information for Leqembi carries a boxed warning that the medication can cause ARIA involving brain swelling and bleeding. Although abnormalities are often asymptomatic, serious, life-threatening and fatal cases can occur.
The FDA in 2025 additionally recommended an earlier MRI for patients receiving Leqembi after safety surveillance identified the value of detecting brain swelling sooner during treatment. The agency said MRI monitoring can help physicians identify ARIA and make treatment decisions before potentially serious complications develop.
Kisunla carries a similar warning. Manufacturer Eli Lilly states that the drug can cause ARIA, most commonly appearing as temporary brain swelling, as well as small areas of bleeding and, less frequently, larger brain hemorrhages. The drug’s safety information notes that serious and fatal cases can occur.
Treatment costs are also substantial. Eisai reported that as of July 2026, the list-price cost of intravenous Leqembi for a 165-pound patient receiving the standard weight-based regimen was approximately $28,270 per year, not including scans, diagnostic testing, infusion services or other medical expenses. Actual patient costs vary significantly depending on insurance coverage and other factors.
The turmeric study should not be interpreted as showing that a dietary supplement offers an equivalent alternative to those drugs. Unlike approved anti-amyloid medications, the extract has not been shown in a large randomized trial to slow the progression of Alzheimer’s disease, and researchers did not compare it directly with Leqembi, Kisunla or any other treatment.
No medically significant safety problems attributed to the extract emerged in the small observational study. The researchers also cited an earlier safety trial in which participants consumed five times the dose used in the current study without adverse findings in physical examinations or laboratory testing.
That safety record, combined with the memory changes observed after four months, gives researchers a basis for conducting more rigorous testing rather than grounds for recommending the extract as an Alzheimer’s treatment.
Larger trials would need to randomly assign patients to the extract or a placebo, follow them for substantially longer periods and determine whether any statistically measurable improvements translate into meaningful differences in everyday memory, independence and disease progression.
They would also need to establish whether the effects can be reproduced by investigators independent of the company supplying the product.
For now, the study adds to a growing body of research examining whether compounds found in turmeric may influence cognitive function. Its strongest finding is not that turmeric has been proved to treat Alzheimer’s disease, but that a specific group of turmeric compounds produced enough of a signal in a small group of patients to warrant a considerably larger and more rigorous test.
Source: Natural News
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