Regular exercise, adequate sleep, meditation, spending time in nature and spending time with friends are all well-established ways to improve our mental state. However, a growing body of research indicates that our diet can also play a role. The overall weight of evidence suggests that the diet pattern most associated with improved mental well-being is a diet rich in unprocessed, plant-based foods. ₂₋₁₀ This means a diet rich in whole grains, beans, fruits, vegetables, nuts and seeds.
Although this area of research is still evolving, we have multiple explanations as to why a diet that emphasizes plants and minimizes animal products is associated with better mental health.
Below are 6 ways we can reap the benefits of a plant-based diet and boost our mood with food.
1 | FILL UP ON FIBERThere are trillions of microbes (mainly bacteria) that live in our large intestine—collectively referred to as our microbiota. There has been a growing interest in the gut-brain axis—the line of communication between our gut and our brain. If you’ve ever been nervous and experienced butterflies in your stomach, you can vouch for the fact that our brain can influence our gut. But we now know the gut-brain axis is a two-way street, in that our gut can also influence our brain. It turns out many neurotransmitters (compounds that our brain uses to communicate) are produced in the gut—an estimated 95% of serotonin and 50% of dopamine. ₁₁ These two neurotransmitters influence the motivation and reward pathways in our brain, which can shape mood and behavior.
2 | GET YOUR ANTI-INFLAMMATORY FIXA handful of studies have found that inflammation is associated with depression and may have a negative impact on our mood. ₁₅₋₁₆ A plant-based diet has been shown to drastically reduce markers of inflammation, which could explain the good vibes that are often associated with such a diet. ₁₇ Some of the best anti-inflammatory foods include berries, green tea, turmeric, ginger, cherries, tomatoes, dark leafy greens and nuts.
3 | LOAD UP ON ANTIOXIDANTS
Antioxidants are compounds that neutralize the cellular damage caused by unhealthy lifestyle factors (smoking, getting sunburnt, exposure to pollution, etc.), as well as the normal wear and tear our bodies experience on a daily basis. We can arm ourselves with antioxidants by eating a diet rich in plants. On average, plants contain 64 times more antioxidants than animal products. ₁₈ Studies have found that diets rich in certain antioxidants are associated with reduced levels of depression and/or improved mood. ₁₉₋₂₁ These specific nutrients include: beta-carotene, a pigment found in orange fruits and vegetables, such as sweet potatoes, carrots, pumpkin, cantaloupe and mango; lutein and zeaxanthin, which are pigments largely found in dark leafy greens; and lycopene, a pigment found in tomatoes and watermelon.
Check out our 5th Pillar of Nutrition to learn more about the importance of antioxidants.
4 | SKIP THE MEAT
A meat-heavy diet contains very few antioxidants, promotes inflammation and causes unfavorable changes to our gut microbiota, all of which could have unfavorable effects on mood and mental well-being. ₂₂ A meat-rich diet may also be high in arachidonic acid, a fat that research suggests may disturb mood when consumed in large amounts. ₂₃ On top of all that, there’s a philosophical and spiritual argument against eating meat.
Many religious groups tend to avoid meat, including Buddhism, Jainism and Rastafarianism, due to beliefs of non-violence and karma. Some people believe when we consume the flesh of a dead animal that experienced significant trauma while being slaughtered, we are consuming their stress. Although there are no studies to confirm or refute this (that I’m aware of), we can measure levels of the stress hormone cortisol in slaughtered animals. The more stressed the animal, the higher their cortisol levels are at death. ₂₄ Studies show that people eating more meat tend to have higher cortisol levels, and in pregnant women, this may actually lead to higher cortisol levels in their offspring. ₂₅₋₂₆
5 | FAVOR HIGH-FOLATE FOODS
Favor high-folate foods: Folate is a B vitamin that’s also referred to as folic acid (which is the synthetic version). Some evidence shows that low levels of folate are associated with depression. ₂₇₋₂₈ Although these studies don’t prove cause and effect, it can’t hurt to make sure we’re consuming adequate folate. Healthy foods rich in folate include dark leafy greens (spinach, kale, etc.), asparagus, brussels sprouts, broccoli, nuts, beans, peas and peanuts.
6 | EAT QUERCETIN-RICH FOODSThere’s a class of antidepressant drugs called monoamine oxidase inhibitors (MAOIs). They work by inhibiting an enzyme that removes neurotransmitters, such as serotonin and dopamine, from the brain. It turns out that a certain plant polyphenol can act like an MAOI. ₂₉ This compound is called quercetin and it can be found in a variety of plant-based foods. Good sources include dill, cilantro, onions, kale, apples, buckwheat, berries, lettuce, broccoli, grapes, beans and tea. But by far the richest source is capers (raw or canned). Although research is limited on how diets rich in quercetin affect mood, why not eat a big salad with greens, herbs and a sprinkle of delicious capers?
THE BOTTOM LINE
It’s well established that a plant-rich diet is good for overall health, and that the brain and body are deeply connected. When we adopt healthy behaviors as lifestyle medicine, we reap the physical and mental benefits that guide us in the right direction on our pursuit of happiness.
NOTE: None of this information is meant to diagnose or treat depression or any other psychiatric illness. As noted, much of this research doesn’t prove cause and effect, but rather shows patterns of association.
- World Happiness Report 2020
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