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Did you know that food plays a major role in the health of your brain? When you eat the right foods, you increase blood flow to the brain. Better blood flow means better brain function, including improved memory and focus. When experts talk about foods to improve brain function, they usually fall into one of two camps. Firstly, specific nutrient-rich foods or secondly, certain diets such as the keto diet and Mediterranean diet.
Rather than choose sides, we’re here to explain why harnessing the best of both worlds will yield the best result for your brain.
Nutrient-rich foods for brain function
Brightly colored plant foods are rich in antioxidants and phytochemicals responsible for decreasing inflammation, reducing oxidative stress and improving blood flow to the brain, all of which improve brain function. So too are specific nutrients found in certain animal foods, including zinc, choline and omega-3 fatty acids. These nutrients are found in the foods that make up the cornerstone of the Mediterranean diet.
Mediterranean and Ketogenic diets
The Mediterranean diet is highly correlated with improved cognition in people over the age of 65, as well as slower rates for cognitive decline. While this diet focuses on high intakes of nutrient-rich foods, it is also important to note that it limits or avoids refined starches, sugar, pastries, fast food, trans fats and red meat. There is no one specific food list associated with the Mediterranean diet, as it is a compilation of food patterns of the countries surrounding the Mediterranean Sea.
The ketogenic diet has been around for a century, initially used to treat people with epilepsy. In more recent years, we have come to understand the benefits of the keto diet for brain function.
Many people think that a ketogenic diet is just a high-fat, low-carbohydrate diet. While that is true, the point of a ketogenic diet is to drop blood sugar levels and use up glycogen stores so the body can switch to burning stored fat or using dietary fat to produce ketone bodies, or ketones. This is done in the liver. It also improves insulin resistance, which is thought to be a causal factor in Alzheimer’s disease. The typical ketogenic diet is 70-80% fat, 5-10% carbohydrates and 10-20% protein. But it is important to choose your foods wisely. Select anti-inflammatory fats such as olive oil and avocado oil; focus on non-starchy vegetables; and choose high-quality protein such as grass-fed, organic or pasture-raised chicken and beef and wild-caught fish.
Fasting has benefits too
Fasting is another way to put your body into ketosis. Some health practitioners believe that jumping into a 48-hour fast is the quickest way to get into ketosis. While many people might bristle at the idea of a complete absence of food, using intermittent fasting, or time-restricted eating (whereby you only eat within a shortened window of time) can also get the body into ketosis, especially when combined with a very low-carb, high-fat diet.
Ketosis benefits brain function by increasing the number and performance of mitochondria (the powerhouses of your cells). Ketones are actually more efficient than glucose in producing ATP in the mitochondria and with less production of reactive oxygen species (ROS). ROS can damage mitochondria and promote inflammation in the body. Because your brain is so reliant on mitochondria, it’s the first to suffer the damage of oxidative stress.
Ketogenic diets and fasting also upregulate the production of BDNF (brain derived neurotrophic factor). BDNF is a vital neurochemical responsible for the growth and maintenance of neuronal connections which helps your brain adapt and learn.
When it comes to mood, the ketogenic diet has been shown to decrease anxiety and depression by decreasing inflammation of the brain, improving mitochondrial function and balancing neurotransmitters in the brain that are responsible for focus and relaxation.
The winning combination
Marrying the nutrient-rich foods of the Mediterranean diet and the ketone production of the ketogenic diet makes sense when it comes to improving brain function. Once your body adapts to using fat as fuel, there are opportunities to increase carbohydrate intake. The variables that make us all unique – age, gender, body composition, insulin sensitivity and activity level – will determine the macronutrient intake that will help achieve brain health goals. Always work with a qualified healthcare practitioner before embarking on any major dietary changes.
Top 10 foods for brain function
Keeping the above dietary strategies in mind, here are some of the top nutrient-rich foods for brain health to keep on hand.
Choline, found in the egg yolk, is a building block for the neurotransmitter acetylcholine, which supports memory. Choline is more bioavailable when the egg yolk is less cooked, so go for sunny side up eggs.
2. Fatty fish
Wild Alaskan salmon, mackerel, herring, wild Pacific halibut, and sardines are excellent sources of anti-inflammatory omega-3 fatty acids. Omega-3s help build cell membranes and increase blood flow in the brain, which is linked to better cognition.
3. Nuts and seeds
They are a good source of the antioxidant vitamin E, which protects cells from oxidative stress caused by free radicals. Sunflower seeds, almonds and hazelnuts are the highest in vitamin E.
Cacao contains flavonoid antioxidants which protect arterial lining, and l-arginine, a vasodilator, which allows more blood flow to the brain. The flavonoids may also encourage neuron and blood vessel growth in parts of the brain involving memory and learning.
5. Green tea
The numerous compounds in green tea, including l-theanine and EGCG, help to reduce anxiety, improve memory and attention, and improve neurotransmitter production associated with reduced stress.
6. Leafy greens
Kale, chard, spinach and other leafy greens are often touted as superfoods and for good reason – regular consumption enhances brain function by decreasing inflammation and slowing the rate of cognitive decline with age.
Rosemary increases blood flow to the brain, which may help to improve concentration and memory.
8. Extra-virgin olive oil
High in anti-inflammatory monounsaturated fatty acids and polyphenols, olive oil is a staple in the Mediterranean region and contains a high level of antioxidants which have been shown to help protect the brain.
This root vegetable is high in nitrates which get converted to l-arginine, allowing more oxygenated blood to reach the brain.
Strawberries, blueberries, blackberries and raspberries are all high in flavonoids which can protect the brain from oxidative damage. This, in turn, helps prevent premature aging and dementia. The antioxidants in berries may also improve communication between brain cells and help brain cells form new connections, boosting learning and memory.
For more information on the keto connection, read Could the Keto Diet Reduce Your Risk of Alzheimer’s Disease. And for supplements to help keep your brain in shape, check out Keep Your Brain Healthy With These Key Supplements and Herbs.