5 Key Nutrients To Help Slow Brain Aging

Are you getting enough?

By Austin Perlmutter, MD

As the global population ages, aging of the brain and the associated risk for cognitive decline are growing public health concerns. While no single strategy can guarantee lifelong brain health, a growing body of scientific research shows nutrition plays a key role in how the brain ages. Specific nutrients appear to influence inflammation, synaptic plasticity, and even structural integrity of brain tissue, and may translate into a lower risk for age-related brain changes as well as dementia. This article reviews the latest science on clinically studied dietary nutrients that may help aid in slowing brain aging and protecting our brain function over our lives.

1. Omega-3 Fatty Acids: Supporting Brain Volume and Function

Omega-3 fatty acids (commonly called “omega-3s” are a form of unsaturated fatty acid present in our diet and in high concentrations in our brains. Of note are EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid), which come primarily from marine dietary sources like fish and algae. EPA and DHA are crucial for maintaining neuronal membrane integrity and keeping neuroinflammation in check.

A 2014 study published in Neurology found that higher blood DHA and EPA levels were associated with larger total brain volume and hippocampal volume in postmenopausal women. These results were confirmed in 2022, with a larger study finding that higher levels of these omega-3 fats in the blood correlated with a bigger hippocampus and better cognitive function.

Takeaway: Aim for at least two servings of fatty fish weekly, consider supplementation with a combined DHA and EPA supplement which can be fish or algae derived. Low intake of EPA and DHA is of particular concern to vegans, who are unlikely to consume enough through diet alone.

2. Polyphenols: Plant-Based Molecules Linked to Brain Longevity

Polyphenols are an incredibly diverse set of over 8,000 molecules spread across plant foods.  found in spices, herbs, dark leafy greens, berries, onions, tea, and other fruits and vegetables are believed to help support a host of pathways linked to better brain function and longevity. The potential value of polyphenols may help to explain why foods and beverages containing higher levels are linked to better brain health metrics. As an example, in a Nature Translational Psychiatry article from 2022, those consuming tea were 16% less likely to get dementia during a 9-year follow up.

A 2020 study in Neurology looking at 921 participants with an average age of 81 tracked dietary intake of a subtype of polyphenols called flavonols and found that those consuming the most had a 48% lower rate of developing Alzheimer’s over a 6 year period. This study was followed by another observational trial in 2022 in Neurology finding that total flavonol intake was linked to slower decline in cognitive function and less memory loss.

In more recent advanced analysis of polyphenols and brain age, researchers studied the effects of an 18-month intervention focused on increased polyphenol intake and an MRI-based evaluation of brain age. This study, published in November of 2024, found that a younger brain age was driven by higher intake of polyphenols.

Takeaway: Polyphenols are ubiquitous in minimally processed plant foods (there are lower levels in animal-based foods). Some excellent sources include nuts, seeds, spices, tea, coffee, and any colorful fruit or vegetable. While there’s no consensus on optimal daily intake, some data suggests around 1200 mg of dietary polyphenols on top of a healthy diet to support brain health.

3.  Magnesium: A Mineral That Supports Brain Function

Adequate dietary magnesium intake has been linked to multiple aspects of good brain function. The connection may stem from the multiple key roles of magnesium in brain health and brain aging, including regulation of neuroplasticity, inflammation and oxidative stress in the brain. More recently, a link between low dietary magnesium and dementia has been described.

Higher intake of dietary magnesium has been linked not only to lower risk for dementia, but also to lower risk for progressing from healthy brain function to mild cognitive impairment (MCI). In an especially impressive recent review of over 500,000 people from the UK Biobank sample, higher daily intake of dietary magnesium was found to be linked to larger brain volumes and especially larger hippocampi (the brain’s memory center) in men and women.

Takeaway: High magnesium foods include spinach, Swiss chard, pumpkin seeds, chia seeds almonds and legumes. For those seeking more tailored intervention, working with a healthcare practitioner to test levels and considering supplementation can be helpful.  

4. Creatine: Fuel for the Aging Brain?

Best known for its role in muscle performance, creatine is emerging as a brain nutrient, especially for aging populations. Creatine appears to help regenerate ATP, the energy currency of the cell. This may be especially relevant for taxed brain (due to sleep deficit or potentially age-associated energetic issues). While creatine occurs naturally in animal-based foods, it is usually studied at higher levels attained through supplementation.

A 2022 review published in Nutrition found that creatine supplementation was linked to improved memory in healthy people, especially those aged 66-76. In a 2024 paper in Nature Scientific Reports, higher doses of creatine supplementation were found to enhance brain function after sleep deficit. Though preliminary, these types of data suggest that there may be value in creatine supplementation for older adults seeking to enhance and protect brain function.

For those seeking to learn more about creatine supplementation, the preponderance of the research has focused on 3-5 grams a day of creatine monohydrate dosing.

5. Dietary Fiber: Feeding the Gut to Nourish the Brain

The gut-brain axis has emerged as a critical factor in brain health, and dietary fiber plays a central role. Fiber-rich diets promote the growth of beneficial gut bacteria that produce short-chain fatty acids (SCFAs), like butyrate, which reduce inflammation and support blood-brain barrier integrity. Most people do not consume the recommended daily amount of fiber (roughly 14 grams per 1,000 calories, or around 25 grams for women and 38 grams for men)

Higher dietary fiber intake has been linked with better cognitive function in adults aged 60 or above, with one study of 1070 adults specifically finding benefits to intake up to 34 grams a day. Another observational study in roughly 3000 people found that consuming more dietary fiber correlated with an over 25% lower risk for developing dementia over a 20-year period. In a recent preprint study, researchers looked at brain gray matter and compared these results with dietary quality, finding that more dietary fiber correlated with more gray matter volume, including in the hippocampus.

Next steps: prioritize daily fiber from fruits, vegetables, legumes, seeds, nuts and whole grains to support your brain via your gut.