What’s normal?

Scientists used to think that neurons—the specific type of brain cells that allow us to think, learn, remember, make decisions, see, smell, taste, feel, and move—increasingly die as we age, but modern research has debunked that theory. According to John Morrison, PhD, professor of neurology at University of California Davis, if you age without a neurodegenerative disease such as dementia, Alzheimer’s, or Parkinson’s, “you don’t lose a significant number of neurons.”¹ In fact, research has found that our neurons decline very little with normal aging, with an estimated loss of only two to four percent in a lifetime.² Science has also shown us that our brains have the ability to change and grow throughout our lifetimes, allowing us to continue to learn new skills and form new memories as we age.³ This is called brain plasticity, and includes the brain’s ability to grow new neurons and synapses, the points at which neurons communicate with each other.

That’s the good news. The bad news is that there are other physical changes in the brain that can lead to mental decline, including shrinking brain mass, slower communication between neurons, and increased inflammation and oxidative stress. These changes are associated with age-related declines in memory, learning, decision making, recalling names and numbers, and the ability to multitask and/or focus.

But even with these physical changes in the brain, it doesn’t necessarily mean you’ll experience a drastic mental decline (remember, dementia is not a normal part of the aging process; it is a neurodegenerative disease). Outside factors—including nutrition and certain supplements—have a strong influence on how well our brains age and can combat those physical changes, helping to reduce shrinkage, promote brain plasticity, and reduce inflammation and oxidative damage.

A Healthy Diet = A Happy Brain

Your diet has a tremendous impact on brain health—our brains rely on a continuous supply of nutrients that affect both the structure and function of the brain (i.e., everything from brain cell health to neurotransmitter production)—and research continues to prove that a poor diet will lead to negative changes in the brain. For example, a study published in 2022 in JAMA Neurology, found an association between the consumption of ultra-processed food and cognitive decline. The study, conducted between 2008 and 2017 analyzed the diets of 10,775 adults between the ages of 35 and 74; results showed that the people who ate the most ultra-processed food had a faster rate of cognitive decline compared to those who ate the least amount.⁴ A more recent study, published in May 2023, concluded that a diet low in flavanols—a family of antioxidants found in tea, apples, berries, grapes, cocoa and other fruits and vegetables—drives age-related memory loss. The study, conducted by researchers from Columbia University and Brigham and Women’s Hospital, found that flavanol intake among older adults was correlated with scores on tests designed to detect age-related memory loss and that replenishing these antioxidants in the flavanol-deficient adults improved performance on these tests. The study builds on previous research that linked age-related memory loss to changes in the hippocampus, a region of the brain that is vital for learning new memories, showing that flavanols improve function in this region.⁵

What constitutes a brain-healthy diet? A study from Columbia University found that people who consistently ate a Mediterranean-style diet had larger brain sizes and less atrophy (shrinking) than those with lower adherence to the Mediterranean-style diet. In the people studied, who averaged 80 years of age, the larger brain sizes were comparable to being five years younger.⁶ This brain-protective effect was confirmed in a separate analysis of 18 studies, with researchers reporting that people who consistently ate a Mediterranean-style diet had a slower rate of cognitive decline, a lower risk of Alzheimer’s disease, and improvements in cognitive function.⁷ The Mediterranean diet emphasizes wild-caught fish, fruits and vegetables, full-fat dairy, legumes, whole grains, nuts and seeds, herbs, and olive oil.

Boost your brain power with targeted supplements

These supplements have been well-researched when it comes to the aging brain, and they run the gamut, from reducing inflammation and oxidative stress to supporting plasticity, neurogenesis, and minimizing brain shrinkage. For most of them we don’t, or can’t, get optimal amounts of from food alone.

DHA & EPA

The omega-3 fats from fish oil are essential for a healthy brain. Period. Healthy neurons contain high amounts of DHA, which keeps these cells flexible and fluid, allowing for information to easily flow from one cell to another—and the better information flows, the better our mood, memory, concentration, and learning are. Both EPA and DHA support neurogenesis, reduce oxidative damage and inflammation in the brain, and DHA has been shown to increase brain-derived neurotrophic factor (BDNF), a protein that plays a critical role in brain plasticity, increasing the growth of new neurons and synapses.^{8 9 10 11} Higher blood levels of EPA and DHA have also been correlated with larger brain and hippocampal volume (the hippocampus is the part of the brain primarily involved in memory).¹² One year-long, placebo-controlled study found that a daily supplement containing 430 mg of DHA and 150 mg of EPA significantly improved short-term and working memory (important for reasoning and decision making) and verbal memory in elderly subjects with mild cognitive impairment.¹³ The majority of us don’t eat nearly enough cold-water, fatty fish to obtain optimal amounts of these important fats, making this a top supplement to add to your routine. To optimize brain health, aim for 3 grams of fish oil daily.

B vitamins

This family of vitamins is foundational for healthy brain function—without the B vitamins, mental performance, brain cell communication, and overall brain function crashes. B1 has been known for decades to influence brain function, with a B1 deficiency leading to changes in the brain similar to those found in Alzheimer’s. B1 is required for our brain cells to use glucose for energy, and low levels have been linked to reduced neurogenesis (the creation of new neurons).¹⁴ Low dietary intakes of the B vitamins have been associated with cognitive decline,¹⁵ while an increased intake of B vitamins has been shown to slow cognitive decline, particularly in those with elevated homocysteine, an amino acid in the blood that has been directly linked to the development of cognitive impairment, dementia, and Alzheimer’s, even at moderately elevated levels.^16 17 18 One study examining the effects of a daily supplement containing folic acid (800 mcg), B12 (50mcg), and B6 (20 mg) for two years in older adults with mild cognitive impairment found that the supplement significantly reduced homocysteine levels, slowed the rate of brain shrinkage, and slowed cognitive decline, particularly in those who began the study with elevated homocysteine.¹⁹

Lutein

This carotenoid antioxidant is mostly known for its role in eye health, but it is also the most dominant carotenoid found in the brain, and there is a strong relationship between how well the brain ages and the amount of lutein it contains. Lutein helps the brain process information faster, with less energy, essentially helping your brain work smarter, not harder. Recent research investigating lutein’s role in the brain in adults over the age of 50 found that high levels of lutein were associated with better scores in several measures of cognitive function, including memory and executive function, which includes reasoning and judgement, planning, focus, and regulating emotions.²⁰ Lutein is particularly important for protecting fats in the brain, like DHA, from oxidative damage.²¹ It also provides anti-inflammatory protection to brain cells, enhances blood flow to the brain, improves communication between neurons (remember, slower communication between neurons is one of the physical changes that happens in the aging brain), and has been shown to significantly increase BDNF. Doses used in studies range from 12 to 20 mg daily.^22 23 24

Beetroot

Beets are an incredible source of dietary nitrates, which the body converts to nitric oxide (NO), a molecule that plays an important role in maintaining normal cognitive function, including promoting plasticity, mitochondrial biogenesis in the brain, and supporting the growth of healthy neurons, as well as learning and memory formation. NO has been found to increase blood flow to the brain, specifically to areas of the brain often associated with degeneration that can lead to dementia.²⁵ NO levels naturally decline with age, and there is evidence that the loss of NO may contribute to cognitive decline.^26 27 A 2021 study including adults between the ages of 70 and 80 found that 10 days of drinking about 3 cups of beetroot juice daily led to enhanced focus on cognitive tests.²⁸

Curcumin

An inflamed brain is a poorly functioning brain, but curcumin has the power to tame that inflammation. Inflammation in the brain reduces BDNF levels, impairs neurogenesis, and can drive brain cell death and brain shrinkage.²⁹ Curcumin, the main active compound found in the spice turmeric, has been well-researched for its powerful anti-inflammatory effects, and a growing body of research is showing that it is also neuroprotective. One trial examining the effect of short- and long-term supplementation with 400 mg of curcumin in adults age 60-85 found that just one hour after supplementation, curcumin significantly improved performance on sustained attention and working memory tasks compared to the placebo. Working memory and general mood (qualified by positive changes in fatigue, calmness, and “contentedness”) were significantly improved following four weeks of supplementation.³⁰ In addition to being anti-inflammatory, curcumin helps regulate levels of important neurotransmitters—brain communication chemicals—that are involved in learning, memory, mood, and behavior; reduces oxidative damage; increases BDNF; and triggers autophagy, the body’s process of clearing out damaged and aging brain cells and other debris that impairs brain function (think of it as your brain’s way of “cleaning house”). This process is critical for brain health, and any glitches in this system can lead to neurodegeneration.^{31 32 33 34}

Ginkgo biloba

Long valued to support cognition and memory, and with a history of safe use, the herb ginkgo biloba continues to impress. A recent study compared Alzheimer’s patients taking 150 mg of ginkgo biloba extract three times a day with patients taking the drug donepezil, which is commonly used to improve mental clarity and functioning in patients suffering from Alzheimer’s disease. After six months, the ginkgo biloba group had similar benefits to donepezil for improvements in cognitive, behavioral, psychological, and functioning scores.³⁵

Multivitamin

A 2022 long-term, randomized-controlled trial compared adults over the age of 65 who took a multivitamin daily with those who took a cocoa extract daily for three years.³⁶ The participants were subject to a variety of cognitive tests at baseline and annually, which measured executive function and memory composite scores. They found significant cognitive benefits for the participants taking the multivitamin. Specifically, improvements in global cognition (which includes attention, memory, language, and verbal fluency), episodic memory (long-term memory), and executive function (the ability to plan, organize, and multitask). There were no benefits seen for participants taking the cocoa extract. The researchers pointed out that the treatment of three years of multivitamin supplementation appeared to slow cognitive aging by 1.8 years, or by 60 percent, and that the benefits were more pronounced in those participants with cardiovascular disease. A multivitamin supplies numerous nutrients that support normal brain function and helps to correct nutritional deficiencies that could increase the risk of cognitive decline and dementia.

The following nutrients have also been researched for their positive effects on the brain: Lion’s mane mushroom has been found to induce the production of nerve growth factor (NGF), a family of proteins responsible for the maintenance, survival, and regeneration of neurons. Research has shown that it improves mild cognitive impairment in older adults (1,000 mg/three times daily).^37 38 39Phosphatidylserine (PS) is a type of fat that is concentrated in the brain where it maintains the structural integrity of neurons and enhances communication between neurons. Supplementation with PS (300-800 mg/day) has been shown to support cognitive function, including short- and long-term memory, learning and recall, focus and concentration, problem solving, and language skills.^40 41 42 And last but not least, the Ayurvedic herb bacopa has been studied for its effect on cognition and researchers have discovered that compounds in the herb enhance communication between nerves, help regenerate synapses, repair damaged neurons, and support neurogenesis. In one study, supplementation with 300 mg of bacopa daily resulted in significant improvement in memory recall, information retention, and verbal learning (it also improved feelings of wellbeing and reduced depression and anxiety scores).^{43 44 45} 

A drastic decline in cognitive function does not have to be a normal part of aging. Reducing inflammation and oxidation in the brain and promoting neurogenesis and brain plasticity are master keys to unlocking brain health throughout our lifetimes, and research is showing that certain nutrients can improve all of these factors. Take action now to keep your brain forever young!  

References

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