22 Best Natural Supplements for Dementia (2024): 500+ Studies Analyzed

Dementia is the name for a group of symptoms associated with an ongoing decline of brain functioning. It can affect memory, thinking skills and other mental abilities. If you are 65 years old, you have a one in eight chance of suffering from significant cognitive decline.

Contents

1. B Vitamins
2. Vitamin D3
3. Omega-3 fatty acids
4. Magnesium
5. Melatonin
6. Creatine
7. Soy Isoflavones
8. TMG and Betaine
9. Ginseng
10. Melatonin
11. Ginko Biloba
12. Green Tea (EGCG)
13. Quercetin
14. Molecular Hydrogen
15. Coconut Oil
16. Lutein (carotenoids)
17. Selenium
18. Zinc
19. Turmeric (Curcumin)
20. Citicoline
21. Combined Metabolic Activators (NR, NAC, L-Carnitine and L-Serine)
22. Centrum Silver Multivitamin
23. Mushroom (Ergothioneine)

Do Vitamins and Supplements Help With Alzheimer's? This practical guide on brain health supplements is based on a comprehensive review of over 500 scientific references and supporting studies. It explores the latest science-backed nutritional interventions for promoting brain health.

A March 2024 meta-analysis, published in the American Journal of Clinical Nutrition, indicates that daily MVM (MultiVitamin Mineral) significantly benefits both global cognition and episodic memory. These findings within the COSMOS (COcoa Supplement and Multivitamin Outcomes Study) trial support the benefits of a daily MVM in preventing cognitive decline among older adults.

A May 2024 study (Nature) suggests that specific nutrients abundant in the Mediterranean diet could be nature’s own anti-aging elixir for the brain, offering a potential new way, aside from medication, to combat age-related cognitive decline. Published in npj Aging in May 2024, the study combined advanced neuroscience and nutritional science techniques to pinpoint nutrient biomarkers associated with healthy brain aging. It focused on 100 cognitively healthy people aged 65 to 75 and examined the effects of fatty acids, vitamins, antioxidants, and carotenoids on brain health. The researchers identified a specific combination of nutrients linked to slower brain aging and improved cognitive performance. These included:

• Fatty acids: vaccenic acid, gondoic acid, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), eicosadienoic acid, and lignoceric acid, found in foods like fatty fish and nuts
• Carotenoids: lutein, lutein, and zeaxanthin, found in fruits, vegetables, and egg yolks
• Vitamin E: found in peanuts, avocado, and fish
• Choline: found in eggs, meat, fish, and dairy

A 2023 scientific review published in the peer-reviewed journal Nutrients discusses the role of micronutrients in neurological disorders specifically, noting that long-term deficiencies may be involved in the cause and subsequent development of neurodegenerative processes and neurological diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis (ALS). 

As noted in this paper, the primary function of micronutrients is their "catalytic effect in enzyme systems, either as cofactors or as components of metalloenzymes." Other essential roles include antioxidant activity and immune modulation. When you're deficient in micronutrients, especially long term, peripheral nerve damage and/or damage to the central nervous system can result, which in turn can contribute to a variety of neurological diseases, including Alzheimer's and Parkinson's.

A 2022 review paper, retrieved a total of 4310 articles and 43 articles to be incorporated in the review. Findings revealed a trend of significant association between low levels of B vitamins (folate and vitamin B12), vitamin D, vitamin A, vitamin E, omega 3 fatty acid, and albumin, and high homocysteine levels in blood with an increased risk of mild cognitive impairment among older adults.

The exact cause of Alzheimer's disease is not yet fully understood, although a number of things are thought to increase your risk of developing the condition.

These include:

• increasing age
• a family history of the condition
• untreated depression, although depression can also be one of the symptoms of Alzheimer's disease
• lifestyle factors and conditions associated with cardiovascular disease

Among the risk factors, oxidative stress (OS) turns out to be one of the primary causes of AD, playing a key role in its pathophysiology and progression (Buccellato 2021).

There are currently no drugs available to prevent, treat, or reverse the course of Alzheimer’s disease. The five FDA-approved medications available for Alzheimer’s are designed to relieve symptoms such as memory loss, for a limited time — Aricept®, Exelon®, Namenda®, Namzaric® and Razadyne®.

There are more than 120 potential drugs in clinical trials now designed to treat the underlying causes of Alzheimer’s, rather than its symptoms. The ADDF (Alzheimer's Drug Discovery Foundation) has supported 20% of these, and many more ADDF-funded treatments are expected to be in human trials this year.

 

What is dementia?

Dementia is a general category of brain diseases that cause long term inability to think and remember. It affects a person’s daily functioning, and usually also causes emotional problems, decreased motivation and eventual loss in language.

Alzheimer’s disease is the most common form of dementia which amounts to 50% to 70% of all cases. Vascular dementia, usually from either multiple strokes or severe atherosclerosis makes up to 25% of cases.

Other causes are Lewy body dementia (LBD), syphilis, chronic mercury, lead, cadmium, and aluminum exposure, Parkinson’s disease, Creutzfeldt-Jacob disease, hypothyroidism, vitamin B1 deficiency, vitamins B12 and folate deficiencies, MTHFR mutation and others.

In March 2023, the Alzheimer’s Association of the United States released its latest data indicating that there are about 6.7 million Americans aged 65 and above suffering from Alzheimer’s disease. Without many breakthroughs in prevention, mitigation, or treatment, it is projected that this number could reach 13.8 million by 2060.

Rates of early-onset dementia and Alzheimer’s disease among Americans younger than 65 have inexplicably doubled between 2013 and 2017, according to data from Blue Cross Blue Shield (BCBS), a health insurance provider.

The average age of someone between 30 and 64 years old living with either young-onset dementia or Alzheimer’s is 49, with women being disproportionately affected compared to men, according to the BCBS data.

Best Natural Supplements for Preventing & Reversing Alzheimer’s and Dementia

The antioxidant connection is a hot area in Alzheimer’s research, but everyone agrees that more still needs to be done. Researchers aren’t sure if some antioxidants are better than others, and it’s possible that it might be better to get your antioxidants from food instead of from supplements.

We have compiled a list below and categorised them with reference links. Note that this list is not exhaustive.

Methodology: The selection or short-listing of the list below is based on the available scientific evidence retrieved from scientific database such as PubMed and scientific search engine such as Google Scholar.

Here are the best natural supplements for dementia that are supported by research.

1. B Vitamins

Vitamins B3, B6, B9 (folate) and B12  may be particularly important for supporting cognitive function as you age, and have been shown to play a major role in the development of dementia, including Alzheimer's disease, which is the most serious (and lethal). (2022)

One theory is that the decline in cognition observed in people with Alzheimer’s disease is due to the disruption of typical energy production and metabolism in the brain.

A systematic review (Wang 2022) of 95 studies found that B vitamins play a crucial role in maintaining brain health and reducing the risk of cognitive decline.

Another paper published in Aging Cell (Dec 2022) on the subject explores whether vitamin B could help offset this disruption. Martens and colleagues found that NR (Nicotinamide Riboside - a member of the vitamin B3 family) supplementation increases NAD+ levels and lowers biomarkers of neurodegeneration in plasma extracellular vesicles enriched for neuronal origin (NEVs). The results suggest NR, by increasing NAD+, could help ward off Alzheimer’s disease (AD).

A 2020 meta-analysis of 243 observational prospective studies and 153 randomised controlled trials concluded that homocysteine-lowering treatment seems the most promising intervention for AD prevention.

 

A 2016 randomized controlled trial suggests that B vitamin supplementation slows cognitive decline in select groups, including people with mild cognitive impairment and high baseline homocysteine levels.

A 2016 study found that higher concentrations of docosahexaenoic acid (DHA) alone significantly enhanced the cognitive effects of B vitamins, while eicosapentaenoic acid (EPA) appeared less effective. When omega-3 fatty acid concentrations are low, B vitamin treatment has no effect on cognitive decline in MCI, but when omega-3 levels are in the upper normal range, B vitamins interact to slow cognitive decline.

A 2014 large meta-analysis of 11 trials did show that while B vitamins lowered homocysteine levels, they did not affect cognitive function.

Homocysteine levels are commonly high in people over 65 and are linked to strokes, coronary artery disease, and dementia. (2010 paper)

The good news is your body can eliminate homocysteine naturally, provided you're getting enough B9 (folate), B6 and B12. One study confirming this was published in 2010. Participants received either a placebo or 800 micrograms (mcg) of folic acid (the synthetic form of B9), 500 mcg of B12 and 20 mg of B6.

The study was based on the presumption that by controlling homocysteine levels you might be able to reduce brain atrophy, thereby slowing the onset of Alzheimer's. Indeed, after two years those who received the vitamin-B regimen had significantly less brain shrinkage compared to the placebo group. Those who had the highest levels of homocysteine at the start of the trial experienced brain shrinkage at half the rate of those taking a placebo.

Reduce Inflammation

Chronic inflammation is a risk factor for cognitive decline and Alzheimer’s disease.

B vitamins, particularly vitamins B1 (thiamine), B2 (riboflavin), and B3 (niacin), have anti-inflammatory properties that can help to reduce inflammation in the brain and protect against cognitive decline.

Vitamin B3 and NAD

Since age is the greatest risk factor for Alzheimer's disease and dementia, supplements that slow aging-related processes may also slow progression of these diseases. An observational study found that older adults have lower levels of the coenzyme NAD+ in their brains than younger adults (Pubmed 2015).

Vitamin B and Omega-3

A posthoc analysis study of the OmegAD trial, published in 2019, concluded that the effect of omega-3 supplementation on MMSE and CDR (measures of cognitive dysfunction) appears to be influenced by baseline tHcy (total homocysteine level), suggesting that adequate B vitamin status is required to obtain beneficial effects of omega-3-fatty acid on cognition.

Niacinamide in Alzheimer's (Clinical Trial)

Niacinamide may also be useful in early Alzheimer’s treatment. In the Nicotinamide as an Early Alzheimer's Disease Treatment (NEAT) study, 1,500 mg of niacinamide is given twice daily.

Related: Best NMN Supplement 2024

2. Vitamin D3 and Dementia

In a study published in March 2023, Vitamin D supplementation was associated with 40% lower dementia incidence versus no exposure.

People with lower vitamin D levels appear to have a higher risk of age-related diseases, including cognitive decline and Alzheimer's. While a few small studies suggest that vitamin D supplementation may improve some aspects of cognitive functions, more studies are required to confirm that it can protect against dementia. Vitamin D is usually safe when used as directed.

Several prospective longitudinal studies including the Cardiovascular Health Study, Austrian Stroke Prevention Study, and Rotterdam Study have demonstrated that low serum vitamin D concentrations are linked to a higher incidence of all-cause dementia/AD or lower cognitive functions (Geng 2022, Zelzer 2021).

Participants (~65 years of age) from a Brazilian cross-sectional study that were diagnosed with dementia showed lower serum vitamin D levels. Interestingly, a rise in each unit of serum vitamin D led to a fall in dementia prevalence by 8%, suggesting that vitamin D may be a meaningful disease-modifiable factor (Santos 2020).

A study by Zhao and colleagues (Zhao 2020) examined if the consumption of vitamin D is associated with the risk of dementia. A multi-ethnic cohort from the Washington Heights-Inwood Columbia Aging Project (WHICAP) comprised more than 1750 individuals over 65 years old without dementia at baseline. At a 5.8-year follow-up, 329 subjects were diagnosed with dementia and those with the lowest vitamin D intake had the highest risk of developing dementia, supporting the concept that higher vitamin D consumption, and its enhanced action thereof, may be beneficial for healthy cognitive functions.

According to Dr. Sage Wheeler, medical director of SageMED in Bellevue, Washington:

When supplementing, vitamin D3 should be combined with vitamin K2, especially in higher doses. When combined appropriately as D3/K2, it can be dosed more aggressively for faster optimization.

Related: Best Vitamin D3 Supplements

3. Omega-3 (DHA)

Docosahexaenoic acid (DHA) is a long-chain omega-3 polyunsaturated fatty acid found in some fish and over-the-counter supplements. It is a building block of the brain involved with numerous cellular pathways.

Increasing your omega-3 fat intake and reducing consumption of damaged omega-6 fats (think processed vegetable oils) in order to balance your omega-3 to omega-6 ratio. Krill oil works well for this because (like wild Alaskan salmon) it also contains astaxanthin, which appears to be particularly beneficial for brain health.

A study published in April 2023 found that long-term consumption of omega-rich foods and supplements led to a 20 to 64 percent decrease in dementia, especially Alzheimer’s disease.

 
A study (Huang 2022) examining nearly 212,000 cognitively healthy people concluded that regularly taking fish oil supplements was significantly associated with lower risks of incident all-cause dementia, vascular dementia, frontotemporal dementia, and other dementia—but not Alzheimer’s disease.

Published in 2022, the Cognitive impAiRmEnt Study (CARES Trial 2), was designed to examine the potential synergistic effects of a combination of omega-3 fatty acids (namely DHA and eicosapentaenoic acid [EPA]), xanthophyll carotenoids (specifically lutein, zeaxanthin and meso-zeaxanthin) and vitamin E (d-α-tocopherol) on the cognitive performance of cognitively healthy older adults. This study provides Class II evidence that 24-month supplementation with 430 mg DHA, 90 mg EPA, 10 mg lutein, 2 mg zeaxanthin, 10 mg meso-zeaxanthin and 15 mg vitamin E (d-α-tocopherol) is effective in improving cognitive performance, namely working memory, in cognitively healthy older adults.

In conclusion, the CARES research has shown improvements in working memory following 24-month supplementation with omega-3 fatty acids, xanthophyll carotenoids (lutein and zeaxanthin) and vitamin E in cognitively healthy older adults. These results support a biologically plausible rationale whereby these nutrients work synergistically, and in a dose-dependent manner, to improve cognitive performance. These findings illustrate the importance of nutritional enrichment in improving cognition and enabling older adults to continue to function independently, and highlight how a combination of omega-3 fatty acids and xanthophyll carotenoids may prove beneficial in reducing cognitive decline and/or delaying Alzheimer's disease onset in later life. (Power 2022).

A posthoc analysis study of the OmegAD trial, published in 2019, concluded that the effect of omega-3 supplementation on MMSE and CDR (measures of cognitive dysfunction) appears to be influenced by baseline tHcy (total homocysteine level), suggesting that adequate B vitamin status is required to obtain beneficial effects of omega-3-fatty acid on cognition.

Increased beneficial effects of macular carotenoids (lutein and zeaxanthin) were also observed upon their intake together with fish oil and omega-3 fatty acids, suggesting a dietary synergism (Nolan 2018).

Many governments recommend eating omega-3 containing fatty fish, two times per week. But that is often not enough. Ideally, people would need to eat fatty fish four times per week, while also supplementing with omega-3 fatty acids, at least 1,000 mg of pure omega-3 (DHA and EPA) per day.

Make sure you buy high-quality omega-3 fatty acid supplements, meaning that the omega-3 fatty acids are pure and have not oxidized much (having low “TOTOX” value).

TOTOX value stands for total oxidation value. The omega 3 fatty acids EPA and DHA from fish oil are highly sensitive to oxidation. This means that they are rapidly affected by contact with oxygen. Oxidised fatty acids are not beneficial to our health. For this reason, a good fish oil supplement has a low TOTOX value. The maximum TOTOX value is set at 26 by the Global Organization for EPA and DHA omega-3.

According to Dr. Sage Wheeler, medical director of SageMED in Bellevue, Washington:

Omega-3 fatty acid supplements come in three types: inexpensive ethyl esters, high-quality triglycerides, and superior monoglycerides. Monoglycerides are 2-3 times more potent due to better absorption, making 1,000 mg of monoglyceride omegas equivalent to approximately 2,700 mg of triglyceride-based omegas, according to Wheeler.

I recommend eating fish 2-3 times per week and taking 2,500-3,000 mg of a monoglyceride formula or 5,000 mg of a triglyceride formula, once per day, with food.

4. Magnesium 

Magnesium (Mg) is an essential mineral for the body and brain, which is needed for the proper functioning of many enzymes that carry out biochemical reactions. Sufficient levels of magnesium are usually obtained through a healthy diet.

A meta-analysis conducted in 2022 concluded that a significant Mg deficiency exists in subjects diagnosed with MCI or AD (Du 2022). These findings suggest that Mg deficiency may be either the result of low dietary intake of Mg or the consequence of disease progression. 

Reduced Mg amount in the AD brain may be attributed to lower circulating Mg levels caused by its reduced dietary intake, or defective Mg transport mechanism. The findings of higher dietary Mg intake are associated with a lower risk of MCI indicating a potential neuroprotective effect of Mg intake or supplementation (Glick 2016).

Another 17-year study that followed more than 1,000 Japanese adults over the age of 60 found that those who consumed more than 200 mg of magnesium per day were 37 percent less likely to develop any type of dementia and 74 percent less likely to develop vascular dementia [Ozawa 2012].

One 2016 pilot randomized controlled trial of 44 patients reported that magnesium L-threonate improved overall cognitive ability for elderly patients with memory complaints (Liu 2016).

How much magnesium do I need? The recommended dietary allowance for magnesium is 310 to 420 mg per day depending on your age and sex, but many experts believe you may need 600 to 900 mg per day, which is more in line with the magnesium uptake during the Paleolithic period.

As noted in Open Heart (BMJ):

“Investigations of the macro- and micro-nutrient supply in Paleolithic nutrition of the former hunter/gatherer societies showed a magnesium uptake with the usual diet of about 600 mg magnesium/day …

This means our metabolism is best adapted to a high magnesium intake … In developed countries, the average intake of magnesium is slightly over 4 mg/kg/day … [T]he average intake of magnesium in the USA is around 228 mg/day in women and 266mg/day in men …”

The key to effectively using higher doses, however, is to make sure you avoid loose bowels as that will disrupt your gut microbiome, which would be highly counterproductive.

5. Soy Isoflavones

Soy isoflavones are polyphenols found in soy products and other plants. They preferentially interact with a type of estrogen receptor involved in cognitive functions. Because they interact with estrogen receptors, soy isoflavones have also been studied for preventing menopausal symptoms and premenstrual syndrome.

A large meta-analysis of 10 randomized controlled trials reported that soy isoflavone supplementation significantly improved overall cognitive function and visual memory in people under 60 years old from non-US countries (Menopause. 2015).

In a large double-blind randomized controlled trial of postmenopausal women, treatment with isoflavone-rich soy protein for several years improved visual memory, but not other cognitive functions compared to control (Ref). More benefits were seen in women between 5–10 years of menopause than those 10 years post-menopause.

In older men and women, soy isoflavones treatment resulted in improved spatial memory and construction, verbal fluency, and dexterity, but worse executive function (Ref).

In young healthy adults, high soy diet for 10 weeks resulted in significant improvements in short-term and long-term memory and in mental flexibility, but not in attention or category generation compared to those in the control diet (Ref). Women, but not men, on the high soy diet also improved in letter fluency and planning.

However, soybean oil is a different kettle of fish. We’ve often warned against the use of soybean oil.  Soybean oil is a source of an omega-6 fat called linoleic acid (LA), which is highly susceptible to oxidation and is typically from GMO seeds. Not only is soybean oil loaded with trans fat, which has been linked to heart disease, soybean oil may also cause irreversible changes in your brain.

6. Panax Ginseng

Panax ginseng is a plant used in traditional Chinese medicine (also known as Korean or Asian ginseng). Its root contains compounds called ginsenosides, which have anti-oxidative and anti-inflammatory effects. Panax ginseng is purported to enhance longevity, promote cognitive functions, and alleviate fatigue.

A meta-analysis of five double-blind randomized controlled trials in healthy subjects reported that Panax ginseng treatment for 8-12 weeks showed improvement in some aspects of cognitive function, behavior, and quality of life, though the evidence was not convincing or consistent across studies (Ref).

A 2020 double-blind randomized controlled trial of 52 healthy individuals reported that Panax ginseng treatment (1 g/day) for eight weeks significantly increased the volume of a brain region important for memory and improved scores on executive function, attention, and memory, effects that were not seen in the placebo group.

In one 2020 systematic review that included two randomized controlled trials for ginseng, both trials showed that ginseng supplementation resulted in significant improvements in cognitive outcomes; however, due to the limitations in the methodological quality of the trials, results have not been conclusive.

The longest placebo-controlled clinical trial included 61 Alzheimer’s patients and lasted two years (Ref). In the low-dose Panax ginseng group (4.5 g/day), cognitive scores (as measured by the Mini-Mental State Examination) improved after 48 weeks, then slightly decreased at 96 weeks. In the high-dose group (9.0 g/day), cognitive scores showed slight improvement at 48 and 96 weeks. In this study, maximum cognitive improvement was observed around 24 weeks, then sustained for two years.

7. Melatonin 

Melatonin is neuro-protective. The brain consumes 20% of the body’s oxygen. All that oxygen passing through the brain makes a toxic byproduct called reactive oxygen species, which can damage nerves and blood vessels.

 

Is Melatonin Good For Alzheimer's?

Melatonin improves sleep, which could theoretically lead to long-term protection against Alzheimer's. A review and meta-analysis on melatonin treatment in Alzheimer's published in Neuroscience & Biobehavioral Reviews (Aug 2021) showed individuals with Alzheimer's improved with more than 12 weeks of treatment.

 

Your brain uses many different antioxidants, including melatonin, to neutralize the reactive oxygen species before they can cause harm. Therefore, it is not surprising that studies (2018) show melatonin seems to provide some protective effect against diseases like Alzheimer’s.

8. Gingko Biloba

Given that the ginkgo biloba tree is among the oldest trees in the world, ginkgo seeds have been used in traditional Chinese medicine and other types of treatment for thousands of years. The sole survivor of trees from 270 million years ago, it releases all its leaves in a golden explosion in just one day (Twitter).

Photo by Han Fei

Ginkgo biloba has been used for centuries to improve cognitive function. 

In a 2016 study published in Nutrition, ginkgo biloba was shown to protect the brain from toxicity associated with aluminum chloride. Exposure to aluminum chloride has been linked to Alzheimer's and other cognitive impairments.

A 2012 study published in International Psychogeriatrics suggests ginkgo biloba may slow the aging process within mitochondria of your cells, which can affect the progression of Alzheimer’s.

There are two meta-analyses in dementia patients. In one analysis (2015), seven studies showed that patients using ginkgo had improved scores on certain cognitive performance tests. Two studies in the same analysis using different assessments, however, did not show a statistically significant difference (Ref). Another meta-analysis (2016) of patients with mild cognitive impairment and Alzheimer's disease showed that after 24 weeks of ginkgo, in combination with conventional medicine, they improved cognitive performance scores (Ref).

Another systematic review (Weimann 2010) of 9 controlled trials found that taking ginkgo biloba supplements was more effective than a placebo for improved cognitive function in people with Alzheimer’s, vascular, or mixed dementia.

According to Cleveland Clinic (2002), an adult dose of 120 to 600 milligrams (mg) of ginkgo biloba per day seems to be effective for addressing memory problems. Some have suggested even better results may be achieved by taking ginkgo in combination with panax ginseng or codonopsis.

Risks and Cautions Related to Ginkgo Intake 

According to the U.S. National Center for Complementary and Integrative Health, intake of ginkgo biloba is thought to be safe for healthy adults when taken by mouth in moderate amounts. Potential side effects of ginkgo may include allergic skin reactions, dizziness, headache and stomach upset. An increased risk of bleeding is possible with ginkgo if you are older, pregnant or have a known bleeding risk. Ginkgo has been shown to interact with blood thinners (anticoagulants), so do not take it if you are currently on a blood-thinner medication. For similar reasons, you should not take ginkgo before undergoing surgery or dental procedures. Also, do not eat raw or roasted ginkgo seeds, because they can cause serious side effects and may be poisonous.

You Need B Vitamins if You Take Ginkgo Biloba 

A word of caution related to ginkgo biloba: Its seeds contain ginkgotoxin (4'-Omethylpyridoxine), an “antivitamin” that may lead to neurological problems in certain people, particularly those who are deficient in certain B vitamins. B vitamins are important not only when you consume ginkgo, but they are also useful in helping to reduce brain shrinkage and prevent degenerative brain diseases (J Epilepsy Res. 2015).

9. Geen Tea (EGCG)

Green tea is prepared from dried leaves of Camellia sinensis, a perennial evergreen shrub. It contains several compounds that are possibly beneficial to brain health, including caffeine, catechins (polyphenols like EGCG), and L-theanine (an amino acid derivative).

Greater green tea consumption was associated with lower risk of dementia in two studies conducted in Japan, with the larger study reporting 27% lower risk in people who drank at least 5 cups a day [R]. Tea drinking was also associated with higher verbal fluency in elderly Chinese people (i.e., 80–115 years old) [R].

Two double-blind randomized controlled trials have evaluated the effects of green tea extract on cognitive functions. One trial in 91 patients with mild cognitive impairment reported that the combination of green tea extract and L-theanine for 16 weeks resulted in significant improvements in memory and attention, particularly in patients who had relatively severe baseline impairment [R]. 

The second trial examined the acute effects of a drink containing 27.5 g of green tea extract and reported that the drink increased brain connectivity associated with working memory and the degree of connectivity correlated with the magnitude of improvement in working memory [R].

10. Quercetin

In this study published in Neuropharmacology in 2015, researchers gave quercetin to mice with Alzheimer’s, injecting them with quercetin every two days for three months. By the end of the study, the injections had reversed several markers of Alzheimer’s, and the mice performed much better on learning tests.

In a separate study published in 2018, researchers gave mice with Alzheimer’s a quercetin-rich diet. Researchers found the diet improved brain function in mice with early-middle stage Alzheimer’s, although it had no significant effect on middle-late stage Alzheimer’s.

You may have heard that coffee is linked to a reduced risk of Alzheimer’s. There’s certainly some research to back that claim up. However, a 2016 research has suggested that quercetin (not caffeine) is the primary compound in coffee responsible for protective effects against Alzheimer’s.

11. Lutein Optimizes Brain Health

While lutein is well-known for its role in eye health, its role in brain health is being increasingly explored. The connection makes sense, since as your vision worsens with age, so too may your cognitive abilities.

The Cognitive impAiRmEnt Study (CARES), was designed to examine the potential synergistic effects of a combination of omega-3 fatty acids (namely DHA and eicosapentaenoic acid [EPA]), xanthophyll carotenoids (specifically lutein, zeaxanthin and meso-zeaxanthin) and vitamin E (d-α-tocopherol) on the cognitive performance of cognitively healthy older adults. 

According to CARES, cognitively healthy subjects aged over 65 years, on a diet supplemented for 2 years with a combination of fish oil, vitamin E, and macular pigments (lutein and zeaxanthin), showed improved cognitive ability, measured by working memory test performance, and increased levels of tissue carotenoids, as well as systemic xanthophylls and omega-3 fatty acid concentrations (Power 2022).

Research shows visual impairment at a distance is associated with declining cognitive function over time, while "maintaining good vision may be an important interventional strategy for mitigating age-related cognitive declines." (JAMA 2018)

Meanwhile, studies support the beneficial effects of lutein on brain health. In a trial of young, healthy adults, supplementation with lutein and zeaxanthin improved levels of these carotenoids in the central nervous system along with boosting cognitive function. (Nutrients 2017)

Among older adults with a mean age of 73.7 years, lutein and zeaxanthin supplementation also improved cognitive function, including boosts in complex attention and cognitive flexibility domains, compared to those taking a placebo. (Hammond 2017)

Men taking part in the study also had improvements in composite memory. These benefits were seen with a daily lutein and zeaxanthin dose equivalent to that found in one-half cup of cooked kale or 1 cup of cooked spinach. (NutritionFacts 2023)

A literature search involving eight clinical trials further revealed that lutein and zeaxanthin in the blood or macula are associated with cognitive performance, and "there is an inverse relationship between a higher amount of macular pigment in the blood and lower risk of mild cognitive impairments or Alzheimer's disease." (Wang 2022)

Your body cannot make lutein, so you must get it from your diet. Following are 10 foods that are particularly rich sources of lutein.

1. Dark leafy greens
2. Carrots
3. Broccoli
4. Egg yolks
5. Red and yellow peppers
6. Sweet corn
7. Avocados
8. Raspberries
9. Cherries
10. Paprika

12. Coconut Oil

Coconut oil has been quite the buzzword over the past several years. It has been touted as a health food and as a cure-all to everything from acne, dry skin, diaper rash and now to Alzheimer’s.

Coconut oil, as we all have been hearing, is a good fat; it contains medium-chain triglycerides (MCTs), which our bodies can use as an alternate energy source by converting them into ketones. Our body’s first source of energy is glucose, and when we run low on glucose, we will break down fat and ketones are the byproduct — the alternate energy source.

According to Cognitive Vitality, a program of Alzheimer’s Drug Discovery Foundation, with Alzheimer's "the ability of the brain to use glucose is impaired. Ketones are an alternative energy source for the brain and might be able to compensate for this impairment."

The Research

Currently, there have been several small trials testing the theory that the MCTs found in coconut oil are beneficial for Alzheimer’s:

• One trial performed on elderly individuals with age-related cognitive decline reported no benefit with the use of an MCT supplement.
• Another trial performed on patients with diabetes showed that MCT supplements preserved cognitive functioning related to hypoglycemia, which can cause a decrease in brain cells, especially if it occurs repeatedly.
• For patients who were carriers of the APOE4 genotype (a genotype that causes atherosclerosis, which in turn increases the risk for certain conditions such as heart attacks, strokes and brain conditions related to cognitive impairment), MCTs were not effective. For patients who were not carriers of this genotype, MCT supplements improved mild cognitive decline.
• There is currently a major trial being performed in the U.S. This study seeks to find whether coconut oil is safe to use in the Alzheimer’s population and whether it is effective in improving memory and cognition.
• Another study surrounded men and women with Alzheimer's disease or mild cognitive impairment. The participants were given either MCTs or a placebo. The researchers found that those who were given MCTs had increased memory improvements. This type of research led Emilie Reas, a postdoctoral fellow at UC San Diego who studies brain changes with aging and disease, to conclude that ketones (such as those from coconut oil) may be a "miracle treatment."

As with any health food supplement, it is important to break down the science and ensure that there is adequate research to back up any claims. When it comes to coconut oil, the results look promising.

13. Molecular Hydrogen

Molecular hydrogen (H2) is a gas that is found in trace amounts in the air (0.00005%). It can act as an antioxidant and is thought to protect cells from oxidative stress-related damage. Hydrogen can be inhaled as a gas at low concentrations (1-3%) or infused into water. A saturated solution of hydrogen contains 1.6 parts per million (ppm) hydrogen. In preclinical models, molecular hydrogen was most beneficial when used chronically as a preventative measure, before the onset of pathology. Hydrogen therapy is generally considered safe.

A few clinical trials have tested whether molecular hydrogen preserves cognitive function in populations at high risk for cognitive decline, in the form of hydrogen-rich water, hydrogen-rich saline infusions, or hydrogen gas inhalation. 

In the trial of 73 people with mild cognitive impairment (2018), APOE4 carriers were the only subgroup to show benefits on cognitive tests in response to hydrogen-rich water consumption.

Hydrogen-infused water has been granted Generally Recognized as Safe (GRAS) status by the FDA, which means that it is generally considered safe for consumption.

Read More: A scientific review on the potential of molecular hydrogen in preventing and treating diseases.

14. Selenium

A small randomized, double-blinded, controlled trial comprising patients with AD has shown that co-supplementation of selenium and probiotics improves cognitive function as assessed by MMSE (Tamtaji 2019).

Consistent with this outcome, a meta-analysis of six clinical studies that examined the effects of selenium concluded that the supplementation significantly increases the anti-oxidant glutathione peroxidase activity and enhances cognitive health in either MCI or AD individuals as assessed by MMSE, ADAS-Cog, or Controlled Oral Word Association Test—Verbal fluency (COWAT) (Pereira 2022).

15. Zinc

A number of human studies have established an association between zinc and cognitive health in humans (Leko 2021). 

Subjects 60 years or older from the NHANES study between 2001 and 2004 showed an inverse relationship between zinc intake and cognitive decline (Li 2019). 

As part of the Korean Brain Aging Study for Early Diagnosis and Prediction of Alzheimer’s disease (KBASE), a 2017 study observed that in cognitively healthy subjects aged between 55–90, lower serum zinc levels were not related to Tau accumulation or AD-signature cerebral glucose metabolism, but were significantly associated with Aβ deposition in the brain (Kim 2021).

These results are in line with markedly lower concentrations of zinc and selenium and higher levels of copper/zinc ratio in AD that are associated with cognitive impairment as assessed by MMSE scores (Socha 2021).

16. Citicoline

In a 2023 review and meta-analysis, six studies (including more than 1,300 patients with mild cognitive impairment, Alzheimer's Disease and post-stroke dementia) were selected for the meta-analysis. Overall, citicoline improved cognitive function. However, the overall quality of the studies was poor with significant risk of bias in favor of the intervention. 

In a 2021 randomized controlled trial (not included in the review above), 100 patients with AAMI (Age Associated Memory Impairment) were randomized.

Dietary supplementation of citicoline for 12 wk improved overall memory performance, especially episodic memory, in healthy older males and females with AAMI. The findings suggest that regular consumption of citicoline may be safe and potentially beneficial against memory loss due to aging.

17. Centrum Silver multivitamin review: Can Centrum Silver Improve Memory in Older Adults?

A March 2024 meta-analysis, published in the American Journal of Clinical Nutrition, indicates that daily MVM (MultiVitamin Mineral) significantly benefits both global cognition and episodic memory. These findings within the COSMOS (COcoa Supplement and Multivitamin Outcomes Study)
trial support the benefits of a daily MVM in preventing cognitive decline among older adults.

One of the studies analysed above was COSMOS-Mind. According to the COSMOS-Mind study published in the journal Alzheimer’s & Dementia (2022), findings showed improved scores in overall cognition, memory, and executive function in the people who took Centrum Silver compared to the people who took the placebo.

The researchers estimated that taking the multivitamin daily for three years translated to a 60% slowing of cognitive decline—about 1.8 years.

“Three years of multivitamin supplementation did improve cognitive function,” Laura Baker, PhD, lead author of the study and a professor of gerontology and geriatric medicine at Wake Forest University School of Medicine, told Verywell. “People with cardiovascular disease appeared to have benefited the most from the multivitamin.”

Over 2,200 adults aged 65 and older enrolled in the COSMOS-Mind trial took part in the study, which was done over three years. The average age of the participants was 73 years old, 60% were women, and 89% were White. None of the participants had a history of stroke or heart attack at the start of the trial.

Read More: Memory and Cognitive Benefits of Multivitamins (2024)

18. Combined metabolic activators

A 2023, randomised, double-blinded, placebo-controlled phase-II clinical trial studied the effect of CMA (combined metabolic activators) administration on the global metabolism of AD (Alzheimer's Disease) patients. One-dose CMA included 12.35 g L-serine (61.75%), 1 g nicotinamide riboside (5%), 2.55 g N-acetyl-L-cysteine (12.75%), and 3.73 g L-carnitine tartrate (18.65%). AD patients received one dose of CMA or placebo daily during the first 28 days and twice daily between day 28 and day 84. The primary endpoint was the difference in the cognitive function and daily living activity scores between the placebo and the treatment arms.

The results indicate that treatment of AD patients with CMA can lead to enhanced cognitive functions and improved clinical parameters associated with phenomics, metabolomics, proteomics and imaging analysis. 

19. Creatine

What is creatine? Creatine, a nitrogenous organic acid naturally occurring in vertebrates, plays a critical role in the energy metabolism of brain cells. Synthesized primarily from arginine, glycine, and methionine, creatine is produced endogenously and obtained through dietary intake.

A 2024 meta-analysis of 16 randomised controlled trials (RCTs), suggests that creatine monohydrate supplementation may confer beneficial effects on cognitive function in adults, particularly in the domains of memory, attention time, and information processing speed.

In a 2023 research, published in Nutrition Reviews, found creatine supplementation enhanced memory performance in healthy adults, particularly those aged 66 to 76 years. The study concluded:

“These beneficial effects from creatine supplementation on memory performance may be related to creatine’s ability to influence brain bioenergetics. For example, creatine elevates phosphocreatine and ATP levels and increases oxidative phosphorylation in synaptosomes and isolated brain mitochondria. In hippocampal neuron cultures, creatine stimulates mitochondrial activity.”

20. TMG and Betaine

Trimethylglycine (TMG) is a form of the amino acid glycine with three methyl groups that are attached to it. TMG is also commonly known as betaine or betaine anhydrous.

TMG functions as a methyl donor. TMG methylates homocysteine, an amino acid that can build up in the blood and raise the risk of heart disease, and converts it into methionine.

Additionally, glycine is also an essential amino acid that helps make proteins and enzymes and may lower the amount of sugar in the blood.

As a methyl donor, TMG may contribute to the facilitation of many biological reactions inside the cell that require the process of methylation and is proposed to help with health issues like oxidative stress and inflammation.

When taken in supplement form, TMG has many positive effects. As mentioned above, it is an essential component in methylation. Methylation is an important biochemical process involved in many different cellular functions, like the copying of DNA, the expression of genes, and the making of proteins. Notably, TMG is proposed to provide the following benefits: lower homocysteine levels, improve athletic performance, have a potential role in cancer and depression, aid individuals with autism, and support cognitive function.

A 2020 meta-analysis of 243 observational prospective studies and 153 randomised controlled trials concluded that homocysteine-lowering treatment seems the most promising intervention for AD prevention.

Blood homocysteine levels may be reduced by TMG supplementation.

Caution: TMG shouldn't also be taken by those who have kidney problems.

21. Turmeric (Curcumin)

This common household spice contains the antioxidant and anti-inflammatory compound curcumin, known for its ability to boost brain tissues. Studies (2008) suggest curcumin may slow the progression of Alzheimer’s by reducing the number of plaques in the brain. Additionally, it may also prevent the buildup and clumping of beta-amyloid proteins.

22. Mushroom (Ergothioneine)

Evidence has suggested that mushrooms, which are a rich source of the potent antioxidants ergothioneine and glutathione as well as vitamin D, may have neuro-protective properties. A 2022 study analysed data from older adults aged ≥ 60 years from the 2011-2014 National Health and Nutrition Examination Survey. Mushroom intake was measured using up to two 24-h dietary recalls and was categorised into three groups (lowest, middle and highest). The study included 2840 participants. Greater mushroom intake was associated with certain cognitive performance tests, suggesting regular mushroom consumption may reduce the risk of cognitive decline.

How to diagnose dementia

Diagnosing dementia can be a challenge. Neurologists use cognitive testing, such as asking patients to subtract 3’s from 100, who were the last three U.S. Presidents, the mini mental examination, CT, and MRI scans with and without contrast and SPECT or PET scans. 

Laboratory and history testing should include complete blood counts, full metabolic panel including a complete lipid panel, lipoprotein (a), fibrinogen, homocysteine, CRP-HS, complete thyroid hormone tests, DHEA-Sulfate, testosterone, estradiol, estrone, progesterone, FSH in women, afternoon resting oral temperatures, apo E genotype, history of diet colas (aspartame), history of MSG, the person’s diet (ratio of protein to fats to carbohydrates), history of chronic stress, alcohol history, what types of fats they consume and their cooking oils, family history of celiac disease or gluten intolerance, mold exposure, food allergies, smoking history, current or past hypertension, etc.

Diet To Prevent Alzheimer's and Dementia

There is evidence that a diet rich in fruits and vegetables, particularly those with high levels of antioxidants, may help to reduce the risk of cognitive decline.

Antioxidants protect the brain against oxidative stress, which can contribute to brain damage and cognitive decline.

Maintaining a healthy and balanced diet is essential to reduce the risk of developing Alzheimer’s disease.

This includes eating various nutrient-rich foods, especially those high in vitamin B12, omega-3 fatty acids, and antioxidants.

The MIND diet is associated with the preservation of cognitive function, likely through its protective effects against cardiovascular disease. The MIND diet, which is based on the established cardiovascular Mediterranean and DASH diets, includes foods and nutrients that have been associated with preserving brain health.

Dr. Nikhil Palekar, medical director of the Stony Brook Center of Excellence for Alzheimer’s Disease and director of the Division of Geriatric Psychiatry, explained that the MIND diet is a low-salt type of Mediterranean diet shown to be beneficial for brain health.

“As it contains antioxidant-rich foods, as well as omega-3 fatty acids,” he said.

A low-salt diet has also been shown to benefit brain functioning independent of its action on improving hypertension.

“Given the above benefits, [the] MIND diet is highly recommended for healthy older adults as a way to reduce risk for Alzheimer’s disease, along with daily moderate-intensity aerobic exercise, cognitive activities, and socialization,” said Palekar.

Saturated Fats

Saturated fats are mostly from animal products such as red meat, processed meat, butter, and cheese, though coconut oil is a plant source that is still high in saturated fat. High intakes of saturated fat can lead to high LDL cholesterol levels. One cohort study in the American Journal of Clinical Nutrition showed a diet high in processed meat specifically had a correlation with an increased risk of dementia.

Family history is a large contributor for the risk of developing Alzhiemer’s. Neal Barnard says in widely watched TEDx talk that avoiding the bad fat can decrease risk of Alzheimers by 80 percent. This is even if you have the APOE-epsilon4 allele, the gene that is linked with Alzheimer’s disease.

Best Brain-Boosting Foods to Include in Your Diet

Healthy fish — Small cold-water fish that are rich in animal-based omega-3 fats but have a low risk of contamination are among your best choices for healthy fish. This includes anchovies, sardines, mackerel, herring and wild-caught Alaskan salmon. The omega-3 they contain is vital to your brain, helping to fight inflammation and offer numerous protections to your brain cells.

Cruciferous veggies and leafy greens — Eating just one serving of green leafy vegetables a day may help to slow cognitive decline associated with aging, helping you to be 11 years younger, cognitively speaking, than your non-leafy green-eating peers (source). They’re a rich source of brain-protective nutrients like folate, vitamins E and K, lutein and beta-carotene (source). Cruciferous vegetables, like broccoli and cauliflower, are equally impressive, in part because they’re good sources of choline, a B vitamin known for its role in brain development.

Eggs — Pastured, organic eggs, particularly the yolks, provide valuable vitamins (A, D, E and K), omega-3 fats and antioxidants. They’re also one of the best sources of choline available. Choline helps keep your cell membranes functioning properly, plays a role in nerve communications and reduces chronic inflammation. Choline is also needed for your body to make the brain chemical acetylcholine, which is involved in storing memories.

Beneficial health-promoting fats that your body — and your brain in particular — needs for optimal function include clarified butter called ghee, organic grass fed raw butter, olives, organic virgin olive oil and coconut oil, nuts like pecans and macadamia, free-range eggs, wild Alaskan salmon and avocado, for example.

In a May 2024 study investigating the relationship between diet and dementia-related death, published in the Journal of the American Medical Association (JAMA), researchers analyzed the diets and health outcomes of more than 92,000 U.S. adults. The findings suggest that regardless of genetic predisposition and overall diet quality, those who included at least seven grams (half a teaspoon) of olive oil per day lowered their risk of dementia-related death by 28 percent compared to participants who reported never or rarely including olive oil in their diet. Also, replacing even one teaspoon, or 5 grams, of margarine and mayonnaise with the same amount of olive oil per day was linked to an 8 to 14 percent reduced risk of death from dementia.

Avocado oil, with a similar fat profile to extra virgin olive oil, might offer comparable benefits. A 2014 study found avocado oil improved cardiovascular risk markers in rats fed a high-sugar diet. Poor cardiovascular health has been linked to cognitive issues.

Palm oil has also shown significant health benefits, with one study highlighting its strong antioxidant effects. Antioxidants can protect brain cells from oxidative stress and prevent cell damage. Oxidative stress can impair neurogenesis, the generation of new neurons in the brain, damaging cognitive function. Like olive oil, palm oil is rich in the antioxidant oleic acid.

Coconut oil has demonstrated neuroprotective benefits, including relieving oxidative stress, reducing neuroinflammation, and improving mitochondrial function, according to research.

Coffee — Increased coffee (and tea) consumption was linked to a lower risk of glioma brain tumor, such that people in the top category of coffee consumption were 91% less likely to have glioma compared with those in the bottom category (source).

Blueberries — Blueberries are rich in phytochemicals linked to improvements in learning, thinking and memory, along with reductions in neurodegenerative oxidative stress. They’re also relatively low in fructose compared to other fruits, making them one of the healthier fruits available. Wild blueberries, which have high anthocyanin and antioxidant content, are known to guard against Alzheimer's and other neurological diseases.

Conclusion

While studies suggest that taking certain supplements may help prevent Alzheimer's, the best way to promote longevity and overall health is to engage in healthy practices like consuming a nutritious diet, engaging in regular exercise, stop smoking and reducing stress.

Although there are no guaranteed ways to avoid Alzheimer’s, The Alzheimer’s Association offers 12 healthy habits to improve brain health and reduce the risk of cognitive decline and, perhaps, Alzheimer’s and dementia as well.

1. Keep your brain engaged
2. Be a lifelong learner
3. Exercise regularly
4. Protect your head—always wear a helmet and seat belt when appropriate to protect your head from injuries
5. Don’t smoke
6. Control your blood pressure
7. Manage diabetes
8. Eat a healthy diet
9. Maintain a healthy weight
10. Manage stress
11. Intermittent fasting
12. Get good quality sleep

By making mindful choices, we empower ourselves to maintain optimal brain health now and preserve it well into the future.

Related: 

Methylene Blue for Alzheimer's Disease

Dr Dale Bredesen's RECODE Protocol for Alzheimer's