Nutritional Strategies for Mental Performance and Long-Term Brain Health

Nutritional Strategies for Mental Performance and Long-Term Brain Health

Nutritional Strategies for Mental Performance and Long-Term Brain Health

In the last blog, we discussed many of the root causes of brain decline including neuroinflammation, oxidative stress, poor cerebral blood flow, insulin resistance, and aging.  

While our main focus was the use of nootropics–both synthetic and naturally occurring compounds–to increase mental capacity, attention, memory, and cognitive speed in your patients, we also touched on the importance of a comprehensive approach to brain health that includes an emphasis on nutrient dense foods, physical activity, stress management, and sound sleep–all factors that have been shown to support the brain–both in the short term and long term.  

Because nutrition plays such a critical role in both short and long term brain function, in this blog, we will discuss five, evidence-based nutritional strategies for cognitive performance and neuroprotection, five foods shown to boost brain performance, as well as four foods that contribute to neurodisruption in your patients. But before we dive into these intriguing dietary strategies, it’s important that you understand one of the newest and most exciting areas of research that connects diet to brain health–that is, the brain-gut connection. A conversation about nutrition and brain health would not be complete without a discussion of where those nutrients are ultimately broken down, absorbed, and assimilated–in the gut.  

The Brain-Gut Connection

We’re all familiar with that gnawing feeling in our guts before a big exam or perhaps the butterflies in your stomach when you’re falling in love, but few of us know just how much our brains connect with our guts and vice versa–how intricately our guts connect with our brains. Science has recently uncovered how gut health is tied to brain function and mood. Here is what we know: 

  • The inner walls of the digestive tract contain a “second brain” called the enteric nervous system or ENS (per Hopkins Medicine [1]). The two thin layers of the ENS comprises more than 100 million nerve cells that line the G.I tract from throat to rectum.  
  • The ENS orchestrates the complex process of digestion by communicating back and forth with the brain in our skulls.  
  • Although we’re still discovering the important implications of this connection, researchers have learned:
    • Irritation of the G.I tract may result in signals being sent to the CNS that trigger certain mood changes, such as depression and anxiety. This could explain why patients with conditions like IBS and functional bowel disorder frequently have mood disruptions as well as why antidepressants–not designed for the gut–can mysteriously ease IBS symptoms. It may be that antidepressants act not only on the nerves of the brain but also on the nerve cells of the gut. 
    • Psychological interventions like CBT, mindfulness, meditation, and antidepressants can improve communication between the brain in our heads and the “brain” in our guts. This cross-talk between the gut and the brain could explain why therapies that benefit the brain often benefit the gut and vice versa.  

But the ENS is only part of the story. There are trillions of cells such as bacteria, fungi, and yeasts that inhabit our G.I tracts, weighing approximately four pounds (per Hopkins Bloomberg Public Health [2]). Together, they are known as the gut microbiome, helping to metabolize nutrients and ward off pathogenic bacteria. These microbes also participate actively in the bidirectional crosstalk between the gut-brain axis, in concert with the vagus nerve, immune cells, hormones, neurotransmitters, and other key players.  

Disruptions in the gut microbiome, such as chronic use of antibiotics or a low-fiber diet that starves the microbiome, can trigger production of inflammatory cytokines or reduced production of cofactors needed for brain function and a positive mood. As a result, such gut disturbances have now been implicated in brain disorders ranging from clinical depression to Autism Spectrum Disorder.  

For instance, a 2020 review [3] found that people with depression have a less diverse gut microbiome than people without depression, as well as higher levels of bacteria that cause inflammation like bacteroidetes and lower levels of anti-inflammatory bacteria like firmicutes. Intestinal dysbiosis and altered gut microbiome is also linked to MS disease progression (a 2018 study [4]). The same is true of chronic pain conditions like fibromyalgia, where an altered subset of bacterial species–either more or less than expected–is observed (per a 2020 review [5]). Adverse childhood experiences (ACEs) such as neglect or abuse are also known to disrupt the gut microbiome, with one study [6] showing that pregnant women with early ACEs have higher levels of the pro-inflammatory gut bacteria Prevotella (per Hopkins Bloomberg Public Health [2]). A 2017 review [7] stated “In addition, bacteria populating the gut microbiota can secrete large amounts of amyloids and lipopolysaccharides, which might contribute to the modulation of signaling pathways and the production of proinflammatory cytokines associated with the pathogenesis of AD.” Fiber is also an important component of brain health since the gut bacteria it feeds produce butyrate, a short-chain fatty acid that supplies brain cells with energy (per Academy of Preventative and Innovative Medicine by Worldlink Medical [8]).  

And while cause and effect is not always clear (what came first, the chicken or the egg?), at the very least we know that the gut and anything that influences the gut has real potential to cause problems in the brain.  

The brain-gut connection is an exciting area of new research with major implications across the fields of neurology, psychology, pharmacology, gastroenterology, and more. As it relates to you as a provider, here is what you should take away: the factors that influence your patients’ gut health, such as dietary patterns, nutritional deficiencies, stress and trauma, fiber intake, use or probiotics/prebiotics, and certain gut-disrupting drugs (i.e- antacids, NSAIDs, and antibiotics) could all have major implications on the mental performance, cognition, mood, and long-term brain health of your patients. Who would have guessed?  

Brain-Boosting Nutritional Strategies

While many nutritional approaches can promote a healthy brain, we’ll discuss five: ketogenic diets, low carb diets, Mediterranean diets, and two variations of the Mediterranean diet. Remember that no approach is “right” or “wrong” for patients. As Neil Rouzier would say, your patients are all snowflakes, with their own unique genetics and backgrounds. For that reason, some dietary strategies work better for some patients than others. As a provider, you should be curious, ask questions, and encourage your patients to experiment with a variety of dietary approaches to find out which works best for them.  

Ketogenic Diets

Keto is all the rave now. If you look around, you’d be hard pressed to find anyone who hasn’t heard of a ketogenic diet, so it’s understandable if you’re cynical about ketogenic diets or see them as another fad diet or money-making gimmick by the diet industry. In reality, ketogenic diets were around long before the diet industry popularized them. 

Actually, ketogenic diets were first used medically to treat epilepsy when no other measures worked, and they were extraordinarily effective, reducing seizures by up to 90 percent (per a 2009 study [9]). Before the advent of insulin, ketogenic and low carb diets were the primary treatment for type two diabetes as well and were very effective. 

So, what exactly is a ketogenic diet? And how does it affect brain function? 

While you’d probably find many answers if you do a google search, a proper ketogenic diet is high in fat, low in carbs, and moderate–not high–in protein. The macros typically break down into 70-80 percent fat, 5-10 percent carbs, and 10-20 percent protein. In general, carbs are reduced to below 50 grams per day (often as low as 20-30 grams), according to Harvard T.H. Chan School of Public Health [10]. The goal of a ketogenic diet is to get the body into the metabolic state of nutritional ketosis. During ketosis, the body switches from burning glucose for energy to burning a byproduct of fat oxidation (from both body fat and dietary fat) known as ketone bodies or simply ketones. By reducing the input of carbs and controlling protein (protein can also spike blood sugar due to glucogenic amino acids), ketosis is induced.  

In the metabolic state of ketosis, not only can weight loss result due to reduced hunger and appetite-stimulating hormones like ghrelin and insulin, increased metabolic rate, and preservation of lean body mass, but nutritional ketosis has direct effects on the brain such as: 

  • Ketones are a more efficient energy source than glucose, which could explain its ability to enhance cognitive function (per a 2013 paper [11].)  
  • Ketogenic diets increase levels of a ketone called beta-hydroxybutyrate (BHB), which research demonstrates improves memory and potentially increases longevity (Medical News Today [12]).  
  • Ketosis protects against neurological diseases like Alzheimer’s Disease, Parkinson’s Disease (PD), ALS, and others (per The Institute of Functional Medicine [13] 
  • A 2020 review of 10 randomized controlled studies showed that adults with mild cognitive impairment or Alzheimer’s Dementia (AD) who adhered to ketogenic diets experienced both acute and long-term improvements in cognition, including better verbal memory and cognitive processing speed.  
  • Can reduce symptoms of Multiple Sclerosis by stimulating mitochondrial growth, reducing oxidative stress, and improving overall mitochondrial function. 

Low Carb Diets

While ketogenic diets have some amazing health benefits–for brain health and otherwise–some patients find ketogenic diets restrictive and may struggle to maintain them long-term–especially the elderly.  

The good news is that even low or lower carb diets can improve brain health. Defining a low carb diet is difficult because there isn’t one standard accepted definition. Some would consider a low carb diet to be anything below the Dietary Guidelines for America’s recommendation of 45-65 percent of calories from carbs, which can range from 200-400 grams of carbs for a typical diet, but many experts consider this recommendation to be too high, especially in light of our climbing type two diabetes and obesity epidemic. One must ask if these recommendations are only driving further sickness.  

Most low carb diets recommend about 50-130 grams of carbs per day (per Healthline [14]). While not ketogenic, this range is significantly lower than what most Americans eat and can produce benefits like weight loss and possibly some –albeit much less–ketone production, which could still offer some of the brain benefits of ketones.  

The other benefits of a lower carb diet include less restriction and more room for the occasional treat along the backbone of a lower carb diet, which may improve long-term compliance in your patients.  

In terms of brain function, the benefits are similar–though perhaps less–to ketogenic diets, but if they can be sustained over a long period of time, these smaller benefits could add up. Low carb diets (as well as ketogenic) have been shown to: 

  • Improve memory in older adults (per Healthline [14]). 
  • Reduce migraine occurrence and severity of symptoms. 
  • Reduce symptoms of Parkinson’s Disease (PD). 
  • Reduce insulin resistance, a risk factor for both AD and PD. 
  • Maintaining even very low levels of ketones in the blood is associated with less weight gain over time. 

Mediterranean Diets

Mediterranean diets are another dietary approach popularized for its health benefits. As you would imply, this diet is based on foods commonly eaten in Mediterranean countries such as Italy, Spain, Greece, and Persia.  

Most of the benefits of the Mediterranean diet lies in its emphasis on anti-inflammatory foods, such as fruits and vegetables, fatty fish, poultry, olive oil, avocadoes, legumes, beans, whole grains, lentils, and small amounts of red meat and red wine.  

The diet is also rich in colorful plants, which contain many brain-protective, anti-inflammatory compounds such as carotenoids, resveratrol, and lycopene. The high omega three and Vitamin D content from oily fish provides much of the diet’s powerful anti-inflammatory benefits, protecting against neuroinflammation, which is now linked to several brain ailments ranging from clinical depression to MS to fibromyalgia to Alzheimer’s Disease (per Very Well Health [15]).  

In neurodegenerative disease research, Mediterranean diets have been shown to aid in prevention and slow disease progression as well as improve overall quality of life in patients living with neurodegenerative diseases (per The IFM [16]).  

For example, according to The IFM [16], “In one example, a 2015 randomized clinical trial with 447 cognitively healthy participants supplemented the anti-inflammatory Mediterranean diet with either extra virgin olive oil (1 L/wk) or mixed nuts (30 g/d, which included 15 g of walnuts). While results indicated that both supplemented diets improved overall cognitive performance, only the nut-supplemented diet reported significant improvement for memory testing compared to the control group.” 

The diet helps healthy people too. According to The IFM [16], “…a 2018 double-blind, randomized, placebo-controlled clinical trial suggested that daily supplementation of carotenoids (lutein, zeaxanthin, and meso-zeaxanthin) enhanced memory in healthy adults.”  

A Mediterranean diet is naturally rich in all of these beneficial compounds.  

Variant: Low Carb Mediterranean Diets

There are many variations to the Mediterranean diet, which is typically considered a moderate-carb diet, ranging between 40-50 percent carbs. However, your patients can get the best of both worlds by combining a low carb or even ketogenic macronutrient approach with a Mediterranean eating style.  

This delicious diet emphasizes lower carb Mediterranean foods such as rich sauces, walnuts, avocados, olive oil, fish, green vegetables, berries, and full-fat greek yogurt, while eating smaller portions of higher carb Mediterranean inspired foods like beans, peas, fruit, lentils, and grains. In essence, your patients get all the protective and anti-inflammatory compounds that highlight a Mediterranean style of eating (omega threes, monounsaturated fats, carotenoids, resveratrol, fiber, etc ), while controlling total carbs. 

This dietary variant is especially great for patients with PCOS, insulin resistance, pre-diabetes, and/or diabetes, who can benefit from the anti-inflammatory and glycemia-conscious aspects of the diet.  

Variant: Mediterranean-Dash Intervention for Neurodegenerative Delay (MIND) Diet

Another spin on the Mediterranean diet is the Mediterranean-Dash Intervention for Neurodegenerative Delay or MIND DIET. This diet, developed by nutrition and aging researcher Dr. Martha Morris, SCd, combines principles of the DASH diet with a Mediterranean eating style, emphasizing consumption of dark leafy greens, berries, whole grains, fish, and beans (per Brain and Life [17]). 

A 2015 report out of the journal of the Alzheimer’s Association found that patients who adhered most closely to the MIND diet could reduce their risk of developing Alzheimer’s disease by up to 53 percent! Another 2015 study [18] found that following the MIND diet substantially slowed cognitive decline by an average of nearly eight years 

These foods are also naturally high in minerals like calcium, potassium, and magnesium and low in excess sodium, helping patients with hypertension lower their blood pressures.  

Top 5 Brain Power Foods

Fatty Fish

Fatty fish such as salmon, sardines, and herring come in at the top of the list because they are so rich in omega three essential fatty acids. The two types found in the brain–DHA and EPA–play a critical role in brain health since the brain is the fattiest organ in the human body (per Healthline [19]).  

DHA is a building block of brain tissue, helping to form brain and nerve cells both in the womb and throughout life (per a 2007 review [20]). To put it simply, DHA is like the legos that makeup our brains.  

EPA has a more functional role, influencing neurotransmitter release, behavior, and mood. Both DHA and EPA control vital brain functions like learning and memory. As a result, supplementation has been shown to improve brain disorders ranging from ADHD to dyslexia to Major Depressive Disorder (MDD) (per Healthline [19], a 2007 review [20]).  

In addition to curbing neuroinflammation, a 2016 review [21] and a 2019 meta analysis [22] link omega three fatty acid deficiencies to both learning impairments and depression respectively (per Healthline [19]).  

Furthermore, a 2020 study [23] linked regular fish consumption to an increase in gray matter in healthy people (per Healthline [19]). Gray matter is rich in nerve cells that control functions like memory and decision making.  

Aside from its abundance of omega threes, many fish are rich in Vitamin D, which has important immunoregulatory roles, such as reducing inflammation. For instance, the results of a 2019 meta analysis [24] that assessed the results of nearly 15,0000 participants across 11 dementia studies showed that Vitamin D deficiency was a risk factor for both dementia and AD. In fact, Vitamin D deficiency could even double the risk for developing AD (per a 2014 study [25]). 

A 2019 systemic review [26]  demonstrated that combined omega-3 fatty acid and Vitamin D supplementation reduced both inflammatory markers and relapse rates in MS patients. Fatty, cold water fish like herring, mackerel, salmon, and albacore tuna contain both nutrients.  


Cocoa powder and dark chocolate containing 70 percent or more cocoa is brimming with brain-healthy antioxidants called flavonoids, as well as other brain-supportive substances like caffeine (per Healthline [19]). It has been shown that the flavonoids in cocoa accumulate in parts of the brain that control learning and memory and can even reduce age-related cognitive decline and memory loss.  

For example, a 2016 study [27] on 900 subjects found that those who ate dark chocolate performed better on mental tasks that require strong memory skills compared to subjects who ate minimal dark chocolate.  

And while many studies show the benefits of cocoa on long-term brain function in aging populations, a 2020 review [28] of 11 studies on cocoa consumption out of the journal nutrients, looked at the effects of cocoa on the cognitive function in 366 young people, to see if cocoa could benefit populations who are young and healthy.  

The results were compelling, with the study concluding, “…studies confirm that acute and chronic cocoa intake have a positive effect on several cognitive outcomes. After acute consumption, these beneficial effects seem to be accompanied with an increase in cerebral blood flow…After chronic intake of cocoa flavanols in young adults, a better cognitive performance was found together with increased levels of neurotrophins….” 

Another exciting interventional study [29] published in the American Journal of Clinical Nutrition drew similar conclusions (per Harvard Health Publishing: Harvard Medical School [30]). For this study, Italian researchers tested the effects of cocoa’s active compound–cocoa flavanols–in 90 healthy, older adults. Subjects were divided into three groups and drank a brew containing the flavanols daily. One group contained low amounts, the second moderate, and the third a high amount of cocoa flavanols. After eight weeks, the subjects who consumed either moderate or high cocoa flavanol drinks experienced significant improvements in their executive function, attention, and memory skills.  


Most people are well aware of coffee’s impact on the brain, but few know why coffee makes us feel more alert and improves our attention and concentration. Sure, coffee is high in caffeine, but how does caffeine work in the brain? Does anything else in coffee give it such powerful brain-enhancing effects? 

Caffeine is a large part of the story. It acts on several neurotransmitters and substances involved in focus, concentration, and memory, such as adenosine, epinephrine, and dopamine.  

Because caffeine is very similar in structure to a neurotransmitter that makes us sleepy called adenosine, it binds to the same receptors adenosine binds to. Adenosine levels tend to rise later in the day as we become more sleepy, but if those receptors are blocked by caffeine, adenosine can’t bind and accumulate as it normally would, making us feel more awake and alert (according to Driftaway Coffee [31]). Caffeine also increases the supply of the excitatory neurotransmitters dopamine and epinephrine, which drive concentration, focus, and feed the brain’s reward center, as well as acetylcholine, crucial to learning and memory.    

A cup of java–maybe more–really could improve brain function. Long-term coffee consumption has been shown to reduce the risk of AD and PD, with the largest risk reduction achieved in adults sipping 3-4 cups daily, according to a 2015 review [32]. Coffee’s antioxidants may be responsible for some of these benefits, so decaf is still an option if your patients are worried about jitters.  

Coffee’s ability to improve attention and focus is proven by many studies. For example, a study [33] conducted by John Hopkins researchers showed that drinking coffee before study sessions helped students retain more information by improving their memories for at least the next 24 hours (per Open Universities Australia [34]).  

And because coffee increases the feel-good neurotransmitter dopamine, a 2011 study [35] showed daily coffee drinkers were 20 percent less likely to feel depressed.

Dark Leafy Greens

Dark leafy green vegetables like broccoli, kale, and spinach are jam-packed with nutrients to support a healthy brain.  

These plants are all high in Vitamin K, a fat-soluble vitamin that is needed to make sphingolipids, another type of fat that is richly concentrated in brain cells (per Healthline [19]). This could be why some studies link a higher intake of Vitamin K with improved memory and cognition. In fact, eating just one cup of raw or one half cup of cooked greens per day resulted in a slower decline in brain function, according to a 2018 study [36] out of the journal Neurology (per Brain and Life [37]).  

According to the study, those who ate 1.3 servings of greens per day had substantially slower cognitive decline than those who ate only 0.09 servings per day.  

In fact, leafy green lovers were the equivalent of 11 years younger in terms of degree of cognitive decline than those who tended to avoid them. Even more profound, the differences persisted when scientists controlled for other factors that could impact brain function such as smoking, alcohol consumption, education, and physical activity. 

Several plant compounds were identified in the study and thought to confer the cognitive benefits of eating greens, such as Vitamin K, lutein, folic acid, nitrates, beta carotene, Vitamin E, and kaempferol.


This bright yellow spice is for more than making tasty curries. Its active plant compound, curcumin, can cross the blood-brain barrier, giving rise to direct effects on the brain (per Healthline [19]). For example, curcumin can improve memory in patients living with Alzheimer’s Disease and has even been shown to clear some of the amyloid plaque buildup, according to studies [38]. 

Turmeric even has positive effects on mental health, increasing levels of the feel-good neurotransmitters serotonin and dopamine in the brain, which has been shown to reduce symptoms of depression and anxiety when combined with standard treatments (per a  2019 meta-analysis [39] and a 2020 review [40]).  

Studies show [41] that curcumin increases brain-derived neurotrophic factor (BDNF)–often nicknamed “Miracle Grow” for the brain because it helps brain cells grow and might even slow age-induced cognitive decline, but research is ongoing. 

What more? A 2018 study [42] of forty middle aged to elderly subjects with mild memory impairment looked at the effects of curcumin supplementation in participants who took 90 mg of curcumin twice per day or a placebo for 18 months (per Medical News Today [43]). The type of curcumin used was a highly bioavailable form called “Theracurmin”. At the end of the study, results revealed that subjects who were supplemented with curcumin experienced a 28 percent improvement in their memory tests compared to the placebo group.  

Foods to Limit or Avoid

Free Sugars

Simple sugars, also known as free sugars or added sugars, make up far too much of the Standard American (SAD) Diet. These include sugars added to foods that are not naturally occurring such as sucrose (table sugar), high fructose corn syrup, as well as some naturally occurring sugars like honey and fruit juice, which differ very little from table sugar in terms of their end effects on the body. Any sugar that is not bound to plant walls is essentially a free sugar.  

The sugar that occurs naturally in milk, vegetables, and fruits is often accompanied by fiber and is therefore not considered simple, though too much sugar from fruit can be problematic too.  

Sugar is added to virtually everything to increase both palatability and shelf-life and is hidden in foods we would hardly suspect, from ketchup to bread. Sugar rewards our brains; plain and simple. It increases feel-good neurotransmitters like dopamine and serotonin, and we are hard-wired to seek it from birth, which the food industry is delightfully aware of.  

For example, a 2007 study [44] out of Plos One found sweets to be more addictive than cocaine (per VeryWell Mind [45])! Though the study was conducted on animals, scientists found that sweetness far surpassed the reward from cocaine.  

Most of the added sugar in our diet comes from sugar-sweetened beverages and hidden sources like condiments and salad dressings. For example, a can of cola has a whopping 41 grams of added sugar. This is alarming, considering the American Heart Association recommends women consume no more than 6 teaspoons (24 grams) and men consume no more than 9 teaspoons (36 grams) of added sugars per day (per [46]).  

The toxic effects of sugar on every aspect of health could fill entire textbooks, but when it comes to the brain specifically, sugar is particularly noxious. Refined carbs and sugar can increase substances known as advanced glycation end products (AGES), which generates high levels of oxidative stress that can damage the brain over time (per Academy of Preventative and Innovative Medicine by Worldlink Medical [47]). A diet high in refined starches and sugars is also strongly linked to insulin resistance, a potent risk factor for Alzheimer’s Disease.  

Diets high in excess sugar can cause an increase in the production of inflammatory mediators and pro-inflammatory cytokines in several tissues, including the brain. This low grade inflammation is linked to insulin resistance, according to a 2022 paper [48] published in the journal Frontiers in Immunology.  

Over time, a diet high in sugar and the insulin resistance that results can contribute to hyperglycemia. High blood sugar levels are known to affect the brain’s functional connectivity–or brain regions that share certain functional properties. It can also cause brain shrinkage or atrophy (per Harvard Medical School [49]). High blood sugar also contributes to small vessel disease, restricting blood flow to crucial regions of the brain, which not only causes cognitive difficulties like memory impairment but can even lead to vascular dementia. This small vessel damage is considered a microvascular complication of diabetes and can cause issues in many other areas of the body, such as damage to penile blood vessels, leading to erectile dysfunction (ED), as well as damage to the eyes and nerves, leading to the conditions retinopathy and neuropathy respectively.  

Processed and Refined Carbs

Because all carbohydrates are eventually broken down into simple sugars, the consequences of a diet high in carbs–especially processed ones–evoke nearly the same negative consequences as a diet high in added sugars.  

The distinction between processed carbs and unprocessed carbs is very important because the quicker a food elevates blood sugar, the more likely it is to induce the metabolic damage aforementioned. Carbs can be a part of a healthy diet when eaten in the right type and the right amount 

The carbs in broccoli act much differently in the body than the carbs in cake because of the extent to which they are processed. While processed carbs are stripped of their fiber and ground to a pulp that quickly elevates blood sugar (think white flours, white rice, pastries, etc.), whole, unprocessed carbs found in foods like beans, seeds, legumes, and vegetables have a much smaller impact on blood sugar.  

Of course, all carbs should be consumed in moderation and for some people even “healthy” carbs can be problematic, particularly in those with a propensity towards insulin resistance, PCOS, and/or diabetes. For these individuals and others, a diet that restricts all carbs may be best.  

Still, avoiding the most refined carbs benefits everyone. Even “whole grains” are a problem because they are still processed even though a little bit of the outer bran is kept in. The wheat is pounded into a fine flour that quickly raises blood sugar despite these efforts. Avoiding or greatly limiting foods like bread, pasta, crackers, and other processed grains–wholegrain or otherwise–is beneficial, as well as opting for lower glycemic grains like whole kernel rye or buckwheat in place of wheat, which has among the strongest glycemic response of any grain.   

While the total amount of carbs your patients should consume will depend on several factors like their personal tolerance to carbs, activity, and hereditary factors, the type of carbs they should be eating is pretty universal. No one is designed to eat the highly refined carbs that we eat today. If so, one in three Americans would not be pre-diabetic (per The CDC [50]).  

Most Americans also eat too many total carbs because fat has been shunned for so long, and we have been incorrectly taught we need carbs to function. Actually, carbs are the only macronutrient we don’t need to function. There are essential fats and essential amino acids , but there are—count them–NO essential carbs. The body can function just fine in a low or no carb setting, often more efficiently due to ketone production, and the few carbs it needs to fuel certain regions of the brain, the liver can easily make it through gluconeogenesis.  

But for the majority of patients who will eat some carbs, we providers should emphasize the importance of both carbohydrate amount and type. The type ranges from low to high glycemic carbs. Low glycemic carbs are digested slowly and have a lower impact on blood glucose levels; whereas highly glycemic carbs are quickly broken down and have a much greater impact on blood sugar.  

Low glycemic carbs are naturally high in fiber and low in sugar and can improve health. High glycemic carbs, on the contrary, are stripped of fiber and most strongly associated with the health problems we see today. They are also addictive. According to VeryWell Mind [45], “In humans, high-glycemic foods have been found to activate regions of the brain associated with the reward response and provoke more intense feelings of hunger than low-glycemic foods. Foods that cause a higher elevation in blood glucose produce a greater addictive drive in the brain.” 

So what carbs should your patients focus on then? Here is a list you can provide them with as a helpful guide: 

Limit or Avoid 

  • Candy and milk chocolate 
  • Cakes, pastries, cookies, pies, and other desserts 
  • Ice cream, sorbet, and other frozen desserts 
  • Donuts and bagels  
  • Processed wheat products such as bread, pasta, pancakes, waffles, and noodles–both whole grains and otherwise  
  • White rice and white flour 
  • White potatoes  
  • High sugar fruits like pineapples, mangoes, grapes, cherries, and bananas  
  • Dried fruits like raisins, figs, and dates 
  • Chips, crackers, pretzels, and other starchy snacks  
  • Processed snacks and foods with added sugars such as boxed cereals, granola, condiments, flavored yogurt, salad dressings, and even bread  
  • Sugar sweetened beverages, fruit juice, soda 
  • “Healthy” sweeteners like honey, agave, molasses, and brown sugar which are virtually identical to table sugar.   
  • Anything “instant” like instant oats, grits, rice, boxed potatoes, etc. If it’s instant, it also raises blood sugar instantly.  
  • Yogurt and dairy products with added sugars, low fat dairy products 

Consume in Moderation 

  • Beans and legumes like peas, black beans, kidney beans, chickpeas, and edamame  
  • Brown rice, wild rice, black rice 
  • Lower-GI [51], starchy tubers like sweet potatoes, jicama, and small, red potatoes 
  • Non-wheat, high fiber grains and cereals like buckwheat, soba, bulgar, millet, steel-cut or old fashioned oats, and rye. Choose intact grains and cereals over flour-based products like bread or pasta as much as possible.  
  • Lower sugar fruits like raspberries, blackberries, lemons, limes, kiwi, grapefruit, and blueberries 
  • Full fat yogurt and dairy products with no added sugars 
  • Higher sugar/starch vegetables like carrots, sweet peas, sweet corn, popcorn, onions, leeks, tomatoes, and beets  
  • Dark chocolate 

No Restriction Required  

  • Nuts, seeds, and nut/seed butter like almonds, cashews, peanuts, and pumpkin seeds, almond butter, etc.  
  • Non-starchy vegetables like dark leafy greens (kale, spinach, collards, beet greens, dandelion greens, broccoli, etc), brussel sprouts, cucumbers, celery, bell peppers, hot peppers, green beans, and lettuce (red lead, romaine, iceberg, etc).  
  • Fatty fruits like avocados, coconuts, and olives.  


Alcohol is a drug that is socially acceptable in our society. Red wine is often praised for its health benefits, but the fact remains that alcohol is a toxin with far more detriments to health than benefits. Because alcohol drifts freely into every tissue in the body, it has effects on every organ, including the brain, where it is actively metabolized.  

That’s why the World Heart Federation recently published a policy declaring no amount of alcohol to be safe, citing a number of studies that increasingly show no amount of alcohol to be safe for human health and that any cardioprotective effects of alcohol are negated by its well-documented risks (per CNN Health [52]). Although unpopular and criticized by some experts for this stance, their conclusions were based purely on reputable, reproducible, science.  

Alcohol has direct toxic effects on the brain such as shrinking brain volume and killing nerve cells, and there is concern that even small amounts of alcohol could induce some type of cumulative damage over time, which is what the research shows. Just one glass of wine a day can reduce brain volume, according to a recent study reported by CNN Health [53] 

Like sugar and refined carbs, alcohol also increases advanced glycation end products (AGES). These highly corrosive molecules can damage the brain. Because alcohol burdens the liver, it can also contribute to insulin resistance, yet another factor linked to brain health. Alcohol also increases inflammation, which is linked to dementia.  

We can all attest to the immediate effects of alcohol on the brain. After a night of heavy boozing, our memory of the night before is foggy or absent altogether. A 2007 study [54] highlights why. In the study, scientists scanned the brains of both inebriated and sober subjects using functional magnetic resonance imaging (fMRI) while teaching various concepts that were to be recalled the next day. Alcohol impaired memory partly via reduced activation in the prefrontal lobe, suggesting that alcohol impairs memory by disrupting regions of the brain used for encoding (learning information).  

Unfortunately, these effects are not solely acute. Repeated blackouts cause nerve and damage that impair memory, and if severe enough can even lead to alcoholic dementia, which has nearly identical symptoms to Alzheimer’s Disease, according to an alcohol rehab center [55]. Severe alcoholics can also develop other dementias like Wernicke’s Disorder and Korsakoff Syndrome, caused by thiamine (Vitamin B1) deficiency that excess alcohol induces, impairing memory, problem solving, or even leading to recall of events that never happened.  

And while these more severe impairments are more common in heavy drinkers, even small amounts of alcohol can lead to white and gray shrinkage over time, which could cause some degree of memory impairment or increase the risk for Alzheimer’s.  

We also know this because of phenomena like “pregnancy brain” where the gray matter atrophies in late pregnancy and suddenly expecting moms are finding their car keys in their refrigerators. But unlike that condition, the effects of chronic albeit low level alcohol consumption on brain matter may not be so reversible. For this reason, you should encourage patients to avoid drinking or drink as little as possible–such as only on special occasions–as opposed to moderate, yet chronic–drinking. 

Trans Fat

At one time, we were told to advise our patients to replace butter with margarine, and that it was good for them because it replaced harmful saturated fat with hydrogenated vegetable oil. We now know nothing could be further from the truth. Hydrogenated vegetable oils (trans fats) are far more lethal than saturated fat ever was. In fact, butter is pretty benign, according to multiple, unbiased studies conducted by major organizations (2020 [56], 2021 research [57]). 

Unfortunately, much of the campaign to support a drastic reduction in saturated fat was not based in science and was instead based in fallacy [58], ego, and the political agenda of a popular scientist named Ancel Keys, who shaped American eating habits in some long-lasting and detrimental ways. The result of that agenda was lethal.  

And while partially hydrogenated oils were recently banned from the food supply [59] because of their proven lethality, fully hydrogenated oils have not been banned because they are much lower in trans fats, but they aren’t totally free of them. Foods like margarine, peanut butter, shortening, packaged snacks, and other ultra-processed foods often contain these fully hydrogenated vegetable oils. Deep-frying foods also creates trans fats through oxidation.  

Trans fats affect the brain in many ways. Firstly, it increases several inflammatory markers, which can feed the neuroinflammation responsible for brain disease. Second, when we eat these fake, man-made fats, our brain cells, which should be built from omega three fats, are instead built with these harmful fats. The firm, rigid structure of trans fat impairs cellular communication between brain cells which has far-reaching implications. A diet high in trans fat also reduces serotonin production, leading to both memory and mood impairment (per Psychology Today [60]). And sadly, there’s more.  

A 2015 study [61] out of the University of California, San Diego found that men younger than 45 who consumed a diet rich in trans fats exhibited traits like poor memory, unstable mood, and even an increase in aggression (per Piedmont [62]). The scary part is that these men were young and experienced memory loss in some of their most productive years. Trans fats can also increase insulin resistance, which is a precursor to diabetes and has significant effects on the brain.  

The results aren’t good for older adults either. A study published in the journal Neurology found that elderly people who consumed diets high in trans fats were significantly more likely to experience a type or brain shrinkage common in Alzheimer’s disease compared to the subjects who consumed less of these harmful fats (per Food Navigator [63]).   

What’s Next?

Now that you understand the many nutritional strategies and foods that can positively (or negatively) affect your patients’ mental performance and long term brain health, you’re probably wondering if there is anything else to learn? Yes! 

That’s why we encourage you to attend our Part II webinar: Nutritional Strategies for Mental Performance and Long-Term Brain Health, where you’ll uncover even more valuable information pertaining to brain health such as: 

  • Which dietary strategies work best for which patients. 
  • How much to eat (“dosing”) of certain foods for optimal therapeutic benefits. 
  • The best forms for superior absorption for certain foods. 
  • Special considerations, concerns, and contraindications related to food.  
  • Discuss a couple more foods shown to boost brain performance.  

And if you haven’t already, be sure to read our blog Brain Supportive Nootropics: Could They be the Key to Better Focus, Attention, and Memory in Your Patients? and download the recorded course that goes along with it: Part I – Brain-Boosting Supplements for Better Memory, Faster Cognition, and Sharper Focus in Your Patients, so you are equipped with all the tools necessary to improve cognition, up brain performance, and support long-term brain health in your patients.  


The Brain-Gut Connection. John Hopkins Medicine. Accessed March 9, 2023. 

Powder J. The Gut Microbiome and the Brain: Emerging science is uncovering connections between the microbiome and mental health. Hopkins Bloomberg Public Health. Accessed March 9, 2023.  

Bastiaanssen TFS, Cussotto S, Claesson MJ, Clarke G, Dinan TG, Cryan JF. Gutted! Unraveling the Role of the Microbiome in Major Depressive Disorder. J Harv Rev Psychiatry. 2020 Jan/Feb;28(1):26-39. doi: 10.1097/HRP.0000000000000243. PMID: 31913980; PMCID: PMC7012351.  

Ochoa-Repáraz J, Kirby TO, Kasper LH. The Gut Microbiome and Multiple Sclerosis. Cold Spring Harb Perspect Med. 2018 Jun 1;8(6):a029017. doi: 10.1101/cshperspect.a029017. PMID: 29311123; PMCID: PMC5983160.  

Minerbi A, Fitzcharles MA. Gut microbiome: pertinence in fibromyalgia. J Clin Exp Rheumatol. 2020 Jan-Feb;38 Suppl 123(1):99-104. Epub 2020 Feb 12. PMID: 32116215. 

Hantsoo L, Jašarević E, Criniti S, McGeehan B, Tanes C, Sammel MD, Elovitz MA, Compher C, Wu G, Epperson CN. Childhood adversity impact on gut microbiota and inflammatory response to stress during pregnancy. J Brain Behav Immun. 2019 Jan;75:240-250. doi: 10.1016/j.bbi.2018.11.005. Epub 2018 Nov 3. PMID: 30399404; PMCID: PMC6349044.  

Jiang C, Li G, Huang P, Liu Z, Zhao B. The Gut Microbiota and Alzheimer’s Disease. J Alzheimers Dis. 2017;58(1):1-15. doi: 10.3233/JAD-161141. PMID: 28372330. 

Russ K. Protecting The Aging Brain. Academy of Preventative and Innovative Medicine by Worldlink Medical. July 26, 2022. Accessed March 9, 2023. 

Kossoff EH, Rho JM. Ketogenic diets: evidence for short- and long-term efficacy. J Neurotherapeutics. 2009 Apr;6(2):406-14. doi: 10.1016/j.nurt.2009.01.005. PMID: 19332337; PMCID: PMC4071763.  

Diet Review: Ketogenic Diet for Weight Loss. Harvard T.H. Chan | School of Public Health. Accessed March 9, 2023.,carbohydrate%2C%20and%2075%20grams%20protein  

Prince A, Zhang Y, Croniger C, Puchowicz M. Oxidative metabolism: glucose versus ketones. J Adv Exp Med Biol. 2013;789:323-328. doi: 10.1007/978-1-4614-7411-1_43. PMID: 23852511.,efficiency%20compared%20to%20glucose%20oxidation  

Cohut M. Keto diet may increase memory, reduce mortality. Medical News Today. September 5, 2017. Accessed March 9, 2023.,researchers%20note%2C%20improves%20memory%20function  

Ketogenic Diet in Neurodegenerative Diseases. The Institute for Functional Medicine. Accessed March 9, 2023.  

Spritzler F. How Low Carb and Ketogenic Diets Boost Brain Health. Healthline. Updated on July 13, 2021. Accessed March 9, 2023.  

Dellwo A. Neuroinflammation in Fibromyalgia: Potential new target for treatment. VeryWell Health. Updated on April 30, 2021. Accessed March 9, 2023.,Alzheimer%27s%20disease  

Neurodegenerative Disease: Improving Outcomes Through Nutrition. The Institute for Functional Medicine. Accessed March 9, 2023.  

Shaw G. How Adding Leafy Greens to Your Diet Could Help Your Brain. Brain & Life. October/November 2018. Accessed March 9, 2023.,about%200.09%20servings%20per%20day  

Morris MC, Tangney CC, Wang Y, Sacks FM, Barnes LL, Bennett DA, Aggarwal NT. MIND diet slows cognitive decline with aging. J Alzheimer’s Dement. 2015 Sep;11(9):1015-22. doi: 10.1016/j.jalz.2015.04.011. Epub 2015 Jun 15. PMID: 26086182; PMCID: PMC4581900. 

 Jennings K. 11 Best Foods to Boost Your Brain and Memory. Healthline. Updated on June 21, 2021. Accessed March 9, 2023.  

Kidd PM. Omega-3 DHA and EPA for cognition, behavior, and mood: clinical findings and structural-functional synergies with cell membrane phospholipids. J Altern Med Rev. 2007 Sep;12(3):207-27. PMID: 18072818.,and%20EPA%20generate%20neuroprotective%20metabolites  

Rathod R, Kale A, Joshi S. Novel insights into the effect of vitamin B₁₂ and omega-3 fatty acids on brain function. J Biomed Sci. 2016 Jan 25;23:17. doi: 10.1186/s12929-016-0241-8. PMID: 26809263; PMCID: PMC4727338.  

Liao Y, Xie B, Zhang H, He Q, Guo L, Subramanieapillai M, Fan B, Lu C, McIntyre RS. Efficacy of omega-3 PUFAs in depression: A meta-analysis. J Transl Psychiatry. 2019 Aug 5;9(1):190. doi: 10.1038/s41398-019-0515-5. Erratum in: Transl Psychiatry. 2021 Sep 7;11(1):465. PMID: 31383846; PMCID: PMC6683166.  

Kokubun K, Nemoto K, Yamakawa Y. Fish Intake May Affect Brain Structure and Improve Cognitive Ability in Healthy People. J Front Aging Neurosci. 2020 Mar 20;12:76. doi: 10.3389/fnagi.2020.00076. PMID: 32265686; PMCID: PMC7103640. 

Chai, B., Gao, F., Wu, R. et al. Vitamin D deficiency as a risk factor for dementia and Alzheimer’s disease: an updated meta-analysis. J BMC Neurol 19, 284 (2019).  

Littlejohns TJ, Henley WE, Lang IA, Annweiler C, Beauchet O, Chaves PH, Fried L, Kestenbaum BR, Kuller LH, Langa KM, Lopez OL, Kos K, Soni M, Llewellyn DJ. Vitamin D and the risk of dementia and Alzheimer disease. J Neurology. 2014 Sep 2;83(10):920-8. doi: 10.1212/WNL.0000000000000755. Epub 2014 Aug 6. PMID: 25098535; PMCID: PMC4153851.  

Welayah Ali AlAmmar, Fatima Hassan Albeesh, Layla Makki Ibrahim, Yasmin Yussuf Algindan, Lamya Zohair Yamani & Rabie Yousif Khattab (2021) Effect of omega-3 fatty acids and fish oil supplementation on multiple sclerosis: a systematic review, J Nutritional Neuroscience, 24:7, 569-579, DOI: 10.1080/1028415X.2019.1659560  

Crichton GE, Elias MF, Alkerwi A. Chocolate intake is associated with better cognitive function: The Maine-Syracuse Longitudinal Study. J Appetite. 2016 May 1;100:126-32. doi: 10.1016/j.appet.2016.02.010. Epub 2016 Feb 10. PMID: 26873453.  

Martín MA, Goya L, de Pascual-Teresa S. Effect of Cocoa and Cocoa Products on Cognitive Performance in Young Adults. J Nutrients. 2020 Nov 30;12(12):3691. doi: 10.3390/nu12123691. PMID: 33265948; PMCID: PMC7760676.  

Godman H. Cocoa: a sweet treat for the brain? Harvard Health Publishing Medical School. February 5, 2015. Accessed March 9, 2023.  

Godman H. Cocoa: a sweet treat for the brain? Harvard Health Publishing Medical School. February 5, 2015. Accessed March 9, 2023.  

Scott. Three Ways That Caffeine Affects Your Brain. Driftaway. April 30, 2015. Accessed March 9, 2023. 

Nehlig A. Effects of coffee/caffeine on brain health and disease: What should I tell my patients? J Pract Neurol. 2016 Apr;16(2):89-95. doi: 10.1136/practneurol-2015-001162. Epub 2015 Dec 16. PMID: 26677204.  

Gatlin L. Caffeine has positive effect on memory, Johns Hopkins researchers say. John Hopkins University. January 12, 2014. Accessed March 10, 2023.  

Does coffee help you concentrate? Open Universities Australia. July 27, 2021. Accessed March 10, 2023.  

Lucas M, Mirzaei F, Pan A, Okereke OI, Willett WC, O’Reilly ÉJ, Koenen K, Ascherio A. Coffee, caffeine, and risk of depression among women. J Arch Intern Med. 2011 Sep 26;171(17):1571-8. doi: 10.1001/archinternmed.2011.393. PMID: 21949167; PMCID: PMC3296361.   

Morris MC, Wang Y, Barnes LL, Bennett DA, Dawson-Hughes B, Booth SL. Nutrients and bioactives in green leafy vegetables and cognitive decline: Prospective study. J Neurology. 2018 Jan 16;90(3):e214-e222. doi: 10.1212/WNL.0000000000004815. Epub 2017 Dec 20. PMID: 29263222; PMCID: PMC5772164.  

Shaw G. How Adding Leafy Greens to Your Diet Could Help Your Brain. Brain & Life. October/November 2018. Accessed March 10, 2023.,about%200.09%20servings%20per%20day  

Reddy PH, Manczak M, Yin X, Grady MC, Mitchell A, Tonk S, Kuruva CS, Bhatti JS, Kandimalla R, Vijayan M, Kumar S, Wang R, Pradeepkiran JA, Ogunmokun G, Thamarai K, Quesada K, Boles A, Reddy AP. Protective Effects of Indian Spice Curcumin Against Amyloid-β in Alzheimer’s Disease. J Alzheimers Dis. 2018;61(3):843-866. doi: 10.3233/JAD-170512. PMID: 29332042; PMCID: PMC5796761. 

 Fusar-Poli L, Vozza L, Gabbiadini A, Vanella A, Concas I, Tinacci S, Petralia A, Signorelli MS, Aguglia E. Curcumin for depression: a meta-analysis. J Crit Rev Food Sci Nutr. 2020;60(15):2643-2653. doi: 10.1080/10408398.2019.1653260. Epub 2019 Aug 19. PMID: 31423805.  

Ramaholimihaso T, Bouazzaoui F, Kaladjian A. Curcumin in Depression: Potential Mechanisms of Action and Current Evidence-A Narrative Review. J Front Psychiatry. 2020 Nov 27;11:572533. doi: 10.3389/fpsyt.2020.572533. PMID: 33329109; PMCID: PMC7728608.  

Sarraf P, Parohan M, Javanbakht MH, Ranji-Burachaloo S, Djalali M. Short-term curcumin supplementation enhances serum brain-derived neurotrophic factor in adult men and women: a systematic review and dose-response meta-analysis of randomized controlled trials. J Nutr Res. 2019 Sep;69:1-8. doi: 10.1016/j.nutres.2019.05.001. Epub 2019 May 9. PMID: 31279955.  

Small GW, Siddarth P, Li Z, Miller KJ, Ercoli L, Emerson ND, Martinez J, Wong KP, Liu J, Merrill DA, Chen ST, Henning SM, Satyamurthy N, Huang SC, Heber D, Barrio JR. Memory and Brain Amyloid and Tau Effects of a Bioavailable Form of Curcumin in Non-Demented Adults: A Double-Blind, Placebo-Controlled 18-Month Trial. Am J Geriatr Psychiatry. 2018 Mar;26(3):266-277. doi: 10.1016/j.jagp.2017.10.010. Epub 2017 Oct 27. PMID: 29246725.  

Whiteman H. Turmeric compound could boost memory and mood. Medical News Today. January 25, 2018. Accessed March 10, 2023.  

Lenoir M, Serre F, Cantin L, Ahmed SH (2007) Intense Sweetness Surpasses Cocaine Reward. J PLoS ONE 2(8): e698.  

Fuhrman J. Negative Effects of Sugar on the Brain. VeryWell Mind. Updated on September 30, 2022. Accessed March 10, 2023.  

How much sugar is too much? American Heart Association. Accessed March 10, 2023.  

Russ K. Protecting The Aging Brain. Academy of Preventative and Innovative Medicine by Worldlink Medical. July 26, 2022. Accessed March 10, 2023. 

Ma X, Nan F, Liang H, Shu P, Fan X, Song X, Hou Y, Zhang D. Excessive intake of sugar: An accomplice of inflammation. J Front Immunol. 2022 Aug 31;13:988481. doi: 10.3389/fimmu.2022.988481. PMID: 36119103; PMCID: PMC9471313.,inflammation%20(39%2C%2040) 

Edwards S. Sugar and the Brain. Harvard Medical School. Accessed March 10, 2023.,brain%20to%20atrophy%20or%20shrink  

Prediabetes – Your Chance to Prevent Type 2 Diabetes. Centers for Diseases Control and Prevention. Last Reviewed: December 30, 2022. Accessed March 10, 2023.,t%20know%20they%20have%20it  

Charles S. Difference Between Glycemic Index and Glycemic Load. VeryWell Health. Published on February 25, 2022. Accessed March 10, 2023.  

LaMotte S. No amount of alcohol is good for the heart, new report says, but critics disagree on science. CNN Health. Last Updated January 20, 2022. Accessed March 10, 2023.  

LaMotte S. Just one drink per day can shrink your brain, study says. CNN Health. March 4, 2022. Accessed March 10, 2023.,number%20of%20daily%20drinks%20rises  

Söderlund H, Grady CL, Easdon C, Tulving E. Acute effects of alcohol on neural correlates of episodic memory encoding. J Neuroimage. 2007 Apr 1;35(2):928-39. doi: 10.1016/j.neuroimage.2006.12.024. Epub 2006 Dec 29. PMID: 17303439.  

How Drinking Affects Memory. Sierra by the Sea. Accessed March 10, 2023.  

Astrup A, Magkos F, Bier D, et al. Saturated Fats and Health: A Reassessment and Proposal for Food-Based Recommendations. J Am Coll Cardiol. 2020 Aug, 76 (7) 844–857.  

Diamond DM, Alabdulgader AA, de Lorgeril M, et alDietary Recommendations for Familial Hypercholesterolaemia: an Evidence-Free Zone BMJ Evidence-Based Medicine 2021;26:295-301.   

Men’s Health Staff. The Fight Against Dietary Misinformation Continues…If we are to beat type 2 diabetes, the truth must be heard. Men’s Health. February 8, 2018. Accessed March 10, 2023.  

Ajmera R. What Is Hydrogenated Vegetable Oil? Healthline. September 25, 2019. Accessed March 10, 2023.  

Stoler DR. Trans Fats: Bad For Your Brain. Psychology Today. June 25, 2015. Accessed March 10, 2023.,well%20as%20adversely%20affecting%20memory  

Galindo Y, LaFee S. Dietary Trans Fat Linked to Worse Memory. UC San Diego Health. June 17, 2015. Accessed March 10, 2023.  

How trans fat affects brain function. Piedmont. Accessed March 10, 2023.  

Gray N. Trans Fat and Nutrient Intake Linked to Alzheimer’s Brain Shrinkage. Food Navigator Europe. January 02, 2012. Accessed March 10, 2023.