The modern relationship with food is complicated.
Think about how many easy dining options exist within 10 minutes of where you live (Just try not to think about it too much). With all that easy, available, and bad-for-you stuff out there, it's no wonder that we have a love/hate thing going on with food.
Still, when we think about what and how we should be eating, the focus is almost entirely on our bodies. We think about weight management, muscle development, or cardiovascular health.
If you're like most people, you spend very little time thinking about the way the things you eat affect your brain. That's probably because the differences in the mirror are easier to spot than variations in mental performance.
But brain health is also impacted by what we consume. Let's explore how what we eat affects our most important organ.
To understand how food can influence the brain, it's important to know exactly what the brain is.
The vast majority (75%) of our brains' chemical composition is actually water. Outside of the immense water content, the brain is made up of fat, proteins, amino acids, micronutrients, and glucose.
The various ways our food interacts with the brain has a lot to do with this composition, and what we need to maintain it.
What You Need
Once you know that most of your brain is made up of water, it probably isn't a giant surprise that water consumption plays a significant role in brain function. Adequate hydration is essential for the flow of nutrients to the brain as well as the removal of toxins.
Omega 3 & 6 Fatty Acids
Outside of water, fat makes up the largest portion of our brain tissue. So the Omega 3 and Omega 6 fatty acids that are so crucial to that composition are obvious nutritional necessities.
But when you realize that our bodies cannot create these fatty acids on their own (They have to be taken in through the diet), they become even more of a dietary priority. Fatty fish, nuts, and seeds are great sources for this crucial building block.
Amino acids are used for multiple purposes including the construction of proteins. For the brain, amino acids are uniquely important because they are precursors for neurotransmitters, which carry signals between the cells of the brain and are integral to its function.
Like the omega fatty acids, essential amino acids cannot be produced by our bodies, and must be consumed. Good sources for essential amino acids include: Eggs, turkey, spinach, broccoli, avocado, and blueberries.
All the cells of your body need small amounts of micronutrients to function effectively. For the brain, the most important micronutrients include: B Vitamins (B6 and B12), folic acid, zinc, copper, iron, and sodium. Antioxidants are also critical for fending off free radicals and preserving brain health.
What You Should Avoid
Trans and Saturated Fats
You likely already know that trans and unsaturated fats are not the best option for your overall health. Just think about where they are commonly found: Cakes, pies, cookies, frozen breakfast sandwiches, microwave popcorn, fried fast foods. The list goes on, but you get the picture.
What you may not know is that trans and unsaturated fats can hurt our brains as well. When these fats are used for the construction of brain cells trans and unsaturated fats can cause issues with the cell membranes, which makes it difficult for neurons to communicate with each other. Mental performance suffers as a result, and some research has even suggested links with the development of Alzheimer's.
If you've ever had a few too many drinks, you already know that alcohol isn't the best thing for your brain. But the effects of alcohol on mental capacity is not limited to intoxication.
Persistent, heavy drinkers actually have demonstrably smaller brains than their sober counterparts, and they exhibit age-related signs of cognitive decline earlier in life.
Mercury is a poisonous heavy metal that serves no dietary or functional food purpose. But it is possible to consume enough mercury to do quantifiable damage to the nervous system, just by eating the foods where it is found.
Mainly, we're talking about seafood. To avoid excessive mercury, it's important to limit consumption of predatory fish with long lifespans. These fish can accumulate mercury content that is in excess of 1 million times what could be found in the waters they live in. Fish varieties to look out for include tuna, orange mackerel, tilefish, and swordfish.
Eating fish is generally a great dietary choice, as they are rich sources of a variety of fats and micronutrients that you need in your diet (many of which are featured earlier in this very article). But care should be taken to limit the intake of relatively high-mercury seafood to avoid the toxic effects of this heavy metal.
The average brain accounts for 2% of total body weight, but consumes 20% of all the energy used throughout the day. That disproportionate energy consumption is why our brains are incredibly sensitive to changes in their energy source: blood glucose (sugar).
Glucose is transported by the blood to all of the cells of our body, where it is used to facilitate their continued function. When blood sugar levels are high there is an abundance of available energy. This resource-rich environment produces elevated mood and mental performance.
But the opposite is also true. When blood sugar levels drop we become sluggish, tired, and irritable.
It stands to reason then, that foods that elevate blood sugar would be ideal choices. The problem is that overly high blood sugar levels damage the body, causing harm to arteries, and even neuropathy. That's why insulin serves to keep levels from going too high.
When we eat foods that release carbohydrates gradually (oats, grains, legumes), the insulin response is minimal, and blood sugar levels remain in a desirable range for long periods. We feel satisfied, and function at a high and stable level mentally.
But foods that introduce large amounts of sugar into the blood (your favorite candy or soda) send blood sugar levels up quickly. Insulin is produced in response, and we get the familiar burst and crash that you've likely come to associate with sweet foods.
Poor diet choices affect your mind as well as your body. The impact may be harder to see and take place over longer time frames, but the food we eat will eventually weigh on our mental and emotional well being.
The good news is that good food choices for your brain are mostly just the same quality food choices you should make anyway. Knowing the way those choices affect your brain may just be a little extra motivation to choose wisely.