The best diet for brain health?

New science on the impact of ultra-processed foods on our brains has been in the news a lot lately, so I’ve been thinking about the the best diet for brain health and the connection between food, mood, and the brain. Spoiler alert: your brain and your mood are directly impacted by your food choices (both now and in the future).

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Back to the best diet for brain health and how the foods we can eat impact our minds.

In my experience, food is the most powerful tool we have to influence our health, both in the moment, as well as long-term when it comes to emotional stability, focus, attention, and clarity.

For me personally, the impact is immediate. I’m sensitive to both gluten and refined carbs, which impact metabolism, inflammation, and gut health in one fell swoop. The number one way I experience this sensitivity is brain fog. I can have a slice of pizza, but I pay the price the next day—I feel out of it, irritable, have trouble focusing, and usually have a low grade headache.

I have so many patients who experience the same and the clarity they feel after a simple 30-day elimination diet is profound. One of my patients recently said to me that she had no idea how she got through life for so long living in a fog. “Since cutting out gluten and processed foods, it’s like I have a new brain,” she said.

Wheat, bread, refined sugar, and processed carbs are just some of the foods that impact our mental health. To have the healthiest mind, growing evidence shows the Mediterranean Diet—a diet high in fruits and vegetables, fiber, nuts seeds, fish, and moderate animal protein consumption—wins.

For the five foods I’m eating every day for optimal brain health and better mood, skip ahead to the takeaways. For the science, read on.

The research says

Just last month a major study published in Nature, which analyzed data from over 180,000 people in the UK biobank data set, showed that a balanced diet—defined as high in plants, nuts, seeds, fiber, fish, and protein—was the best for long-term mental health and cognitive function. The study assessed differences in various brain health domains including mental health, cognitive function, blood and metabolism biomarkers, brain magnetic resonance imaging (MRI) traits, along with longitudinal data on mental health disorders, and genetics.

Based on participants’ food preferences, the study identified four common dietary subtypes:

  • Type 1: Low starch, high veg and protein
  • Type 2: Vegetarian (low protein)
  • Type 3: High protein, low fiber
  • Type 4: Balanced across all food groups

Researchers determined Type 4 was ultimately the best diet for brain health. People who preferred a healthy balanced diet scored best on several measures of brain health: they had the lowest rates of depression and anxiety, the highest rates of well-being and cognitive function, the healthiest blood biomarker levels for brain health (including blood sugar and fatty acids), and the best MRI results.

Those who preferred a Type 3 diet—what I would call the “Big Mac diet” consisting mostly of animal protein and simple starches—had the highest rates of anxiety, depression, and stroke. The balanced diet, which is essentially the Mediterranean diet, had the lowest rates.

Unfortunately, most people aren’t eating a Type 4 diet—73% of the US food supply is ultra-processed, meaning the average American adult gets more than 60% of their daily calories from ultra-processed foods.

People who eat an ultra-processed diet have worse learning and memory, according to a recent study conducted in Australia, and also have higher rates of depression and anxiety, according to another study published in the British Medical Journal this year.

So, if Americans are effectively eating ultra-processed foods, i.e. snacks, for the majority of their food intake, is it any wonder that rates of anxiety and depression are skyrocketing, while diseases like dementia and Alzheimer’s have become leading causes of death? With the evidence as clear as it is, it blows my mind that medical schools and top residency programs still train young doctors to say what you eat doesn’t matter.

The good news is small but meaningful changes in diet have a big impact.

For example, a study presented at the American Society for Nutrition’s annual meeting last year found that people who had at least ½ tablespoon of olive oil a day had a 28% reduced risk of dying from dementia. Research also shows eating fermented foods to support a healthy gut microbiome, results in less depression and anxiety and better cognitive function.

Over time, these small changes can make a significant impact on longevity and brain health.

A meta-analysis published in March found those who eat a Mediterranean diet are 11% less likely to develop all types of dementia and 27% less likely to develop Alzheimer’s.

The Takeaway

You can optimize brain health and mental well-being through the foods you eat every day. Here is what I eat knowing what I know:

  1. EVOO: I eat 1 tablespoon of extra virgin olive oil or greater daily. Usually in salads, or on fish and grains and veggies, but I’ll drink it straight from the spoon if I have to.  
  2. Fermented foods: Sauerkraut (with no-added sugar), full-fat yogurt, or a tablespoon of apple cider vinegar mixed with sparkling water daily helps to support my gut microbes. I also take Parsley’s full-spectrum probiotic nightly for digestion, so I’m not reliant on eating fermented foods alone.
  3. Fish: I eat high-quality, low-mercury fish and seafood at least five times a week in the form of salmon, shellfish, hake, or seabass. It’s great source of omega-3 fats as well as protein.
  4. Gluten-free, whole, plant-based starch: Quinoa, rice, and purple potatoes are my starches. I’m not a zero carb girl, but I limit intake to midday and evening meals, and to ½ cup servings.
  5. Leafy greens: I make sure to get these daily, including kale, chard, and romaine lettuce alongside cruciferous veggies like broccoli, brussels, and cabbage both for the fiber and brain healthy polyphenols.

When the occasional slice of pizza does sneak in, I treat the following day as a brain restorative day starting with detoxifying supplements like Parsley’s Daily Dose Multivitamin and Endura Hydration Powder from Metagenics. I make sure to eat lots of protein, healthy fat, greens, and fiber and zero sugar, gluten, or refined carbs. I usually feel back to amazing by that night or the next morning. Onwards!

If you’re looking to work with a medical team who can tailor personalized nutrition recommendations to your lab test results and risk factors, this is what the Parsley Health team does daily. Learn more with a free call.