MealEnders Blog

How Diet Affects Your Brain

[Plus 5 Ways to Improve Cognition and Mood with Food]

By Tami Lyon, MPH, RD
March 29, 2018

mood food

Is there such a thing as mood food?  Can food affect your mental clarity? Intuitively we all know that the answer to both of these questions is yes, of course, but why is this the case? Let’s take a deeper look at exactly how this works and how you can leverage this information to increase happiness and cognition.

Although we sometimes think of body and mind as two separate entities, they are one and the same. Both are impacted by the quality of your diet. When you eat, food gets broken down in the digestive tract, absorbed, and sent throughout the body to support cellular activity. The brain is a particularly hungry organ since it is constantly at work (orchestrating all thought as well as all unconscious activities, such as breathing). This means that a good portion of the nutrients you consume gets sent directly to the brain. What you eat affects your ability to think as well as your overall mood.  

It’s important to eat nutritious foods that contain complex carbs, high quality proteins, healthy fats, and an abundance of vitamins, minerals, and antioxidants. While the macronutrients fuel your brain and serve as the building blocks for new neurons, the micronutrients (vitamins, minerals, and antioxidants) are crucial for protecting your brain against inflammation and oxidative stress (oxidative stress refers to the damage caused by free radicals).

Diets high in processed foods spike insulin levels and promote inflammation throughout the body–this includes inflammation of your brain. In the short term, this can make it difficult to focus, create brain fog, and increase irritability. In the long term, it can create mood disorders such as depression. Numerous studies have demonstrated this effect–poor diets, high in sugar and devoid of antioxidants, are highly correlated with decreased mental health.

Food affects mood indirectly as well by altering the composition of your gut microbiome. The gut is often referred to as the “second brain.” When the bacteria in your gut aren’t healthy they communicate this to you through the enteric nervous system. The enteric nervous system is a dense network of over 100 million neurons that lines your gut and serves as a telephone line between your gut and your brain. The signals sent by the enteric nervous system affect how you feel and determine your mood. When your microbiome is unhealthy it sends signals that cause us to experience anxiety and depression. On the flip side, a healthy microbiome decreases inflammation, reduces cortisol levels, increases serotonin levels, mitigates your stress response, improves memory, reduces neuroticism, and decreases social anxiety. Clearly, diet has a huge impact on how you feel and how well you operate.

Although there are many things we still have to learn about the gut microbiome, one thing we know for sure is that in order to maintain a healthy and diverse microbiome, it’s important to consume a diet rich in fruits and vegetables. Doing so will ensure that you are are getting plenty of fiber as well as nutrients proven to improve mood such as calcium, chromium, folate, magnesium, zinc, B6, and B12. This is why studies have indicated that traditional diets such as the Mediterranean diet and the Japanese diet, which consist primarily of whole unprocessed plant foods, are correlated with a 25%-35% decreased risk of depression as compared to the standard western diet. Recently, a study conducted by the Rush University Medical Center also linked the DASH Diet (another diet high in fibrous fruits, veggies, whole grains, and beans) to a decreased risk of depression.

Another common thread amongst diets that protect against depression is the emphasis they place on fish as a source of protein. Fish is an excellent source of omega-3 fatty acids and vitamin D. High levels of omega 3s and sufficient vitamin D levels are associated with superior cognitive function and enhanced mood (the lack of Vitamin D in the winter is one of the major reasons why people experience seasonal affective disorder).  

So now that we understand exactly how food affects mood and cognition, let’s take a look at what dietary practices support optimal brain function. Below are five things to focus on if you want to maximize your ability to think clearly and increase your overall happiness:

1) Eat plenty of fruits, vegetables, whole grains, and beans.

This will ensure that you have a healthy and diverse gut microbiome. It also ensures that you are getting all the vitamins and minerals needed to optimize brain health. Below are some of the best mood foods.

Broccoli – high in chromium, which helps regulate insulin and increase levels of serotonin, norepinephrine, and melatonin – three neurotransmitters important for happiness

Spinach – high in folate, which helps support steady levels of serotonin

Lentils – good source of iron. Iron is crucial for proper oxygen transport. Low iron levels can causes fatigue, apathy, and depression

Chickpeas – high in B6, a precursor to dopamine, GABA, melatonin, norepinephrine and serotonin. Again all of these are neurotransmitters that keep you calm and happy.  

Almonds – an excellent source of magnesium, which aids in the development of serotonin. It also assists with sleep and we’ve all experienced how a lack of sleep can cause irritability and decrease our ability to handle stress.

Pumpkin Seeds – a great source of zinc. Zinc plays a key role in maintaining gut health, boosting the immune system, and mitigating oxidative damage throughout the body. As we know oxidation and the resulting inflammation are one of the main reasons we experience things like brain fog, depression, and anxiety.

2) Consume foods that will boost mood enhancing chemicals such as dopamine and serotonin.

These important neurotransmitters are released upon the consumption of high quality proteins such as fish, poultry, eggs, and legumes.  

3) Increase your intake of omega-3s.

Great sources of omega-3s include fatty fish such as salmon, walnuts, flax seeds, and chia seeds.

4) Add in some probiotics.

Fermented foods are the best source of probiotics. Traditionally, these foods have not been staples in the western diet. Sauerkraut, kimchi and tempeh are all wonderful sources of probiotics.  Kefir and yogurt are also great foods for your microbiome (but make sure that they don’t contain added sugar). If fermented foods don’t work for you or you are struggling to eat them regularly, you can always take a probiotic pill instead. When choosing a probiotic pill make sure you choose a brand that has between 1 billion and 10 billion CFUs (colon forming units). To reduce the risk of depression make sure the probiotic contains at least 5 billion cells of bifidobacterium and Lactobacillus acidophilus, both of which have been proven beneficial for improving mood. These strains have been used effectively with other health issues including weight loss, digestive discomfort, and lowering cholesterol. Several brands are BioKult, Nature’s Bounty Probiotic 10, Renew Life’s Ultimate Flora 15 billion, and PB8.

5) Limit your intake of flours, sugars, and processed foods.

These foods have detrimental effects on your microbiome. A 2015 study conducted by Oregon State University discovered that a high-fat/high-sugar diet causes changes in the gut bacteria which decrease cognitive flexibility (the ability to adapt to changing situations), impaired long-term and short-term memory. This means that, while consuming a diet heavy in processed foods any small unexpected changes that occur in life will be more challenging and stressful to handle. It also means that in the long-run you are at greater risk of developing mental degenerative disorders, such as Alzheimer’s disease.

Additionally, we know that high sugar/ high fat diets cause inflammation throughout the body and in the brain. This inflammation creates neuronal damage, which further impairs cognitive function and increases the risk of anxiety and depression.

In transitioning to a diet lower in refined carbohydrates and sugar it’s important to be aware of all the places sugar likes to hide. Some of these include breakfast cereals, ketchup, tomato sauce, other sauces, chocolate milk, bread, and low fat products. Note that “diet” foods and drinks aren’t a good option either. Research indicates that artificial sweeteners are even worse for you than sugar. They more damaging to your microbiome and actually increase your risk of developing diabetes by a factor of two – far greater a risk than if your were drinking sugar-sweetened beverages.



What to Read Next:

Low-Fat Diets vs. Low-Carb Diets
13 Healthy and Satisfying Non-Processed Snacks Under 200 Calories
Maintaining Your Microbiome for Health and Weight Loss

*Individual Results May Vary