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When someone is feeling down, what’s the first question you ask? For most people it’s “Are you okay?” or “What happened?” But according to a growing body of research detailing the connections between nutrition and mental health, the better question might be “What did you eat?”
What is the connection between diet and mental health?
If you’re familiar with the term “sugar crash,” then you likely have a good understanding of how gut health and mental health are intertwined. After all, a sugar crash isn’t just characterized by a lack of energy. Scientifically known as hypoglycemia, when your blood sugar drops, you may feel anxious, irritable, or confused. But because we tend to associate diet with our physical — not mental — wellness, we may not recognize those emotional and cognitive responses as being food-related, despite the “hangry” (so hungry that you’re angry) memes of a few years ago.
Imagine now that you eat a sugar-filled breakfast every morning. That means you’re setting yourself up for a crash every afternoon. You may be blaming your bad mood or anxiety on your commute, your job, or your coworkers when your morning donut and coffee-beverage are actually to blame. A poor diet can worsen symptoms of depression, anxiety, and other mental health conditions.
Why is a healthy diet so important for overall health?
Several studies have begun to link improvements in overall diet to improved mental health. A meta-analysis reviewing 21 studies from 10 countries found that a Mediterranean diet was associated with a reduced risk of depression. A 2019 study examining the diets of older adults found a correlation between anxiety and high sugar intake. And one small but significant study in 2017 found that dietary counseling was more effective than social support when paired with treatment for depression.
A healthy diet has a positive effect on both your mental and physical health. Some of the most notable benefits are:
Reduced inflammation. High inflammation can result in a number of illnesses and chronic conditions. Eating a healthy, anti-inflammatory diet can relieve pain and reduce your risk of illnesses. These include auto-immune disorders, heart disease, inflammatory bowel syndrome, and some cancers.
Improved energy. A balanced diet will help your body convert food into energy more readily. This will keep your energy levels — and mood — more stable throughout the day. Eating excessive amounts of processed and sugary foods provides a lot of calories, but not much in the way of high-quality fuel.
Better sleep. Foods that are high in sugar or hard to digest can make it difficult for your body to rest. Your diet is also your best source of important nutrients that help your body renew and repair itself overnight. Eating a healthy diet is key to getting a good night’s sleep, as well as setting yourself up to feel your best when you wake up.
Gut health and mental health
So what’s the connection between sleep, nutrition, and mental health? The answer is most likely serotonin. If the term sounds familiar, it’s because it’s widely known as the brain chemical responsible for regulating mood. Some of the most common antidepressants (called selective serotonin reuptake inhibitors, or SSRIs) work by managing this neurotransmitter.
While serotonin’s exact function in sleep is unknown, it’s believed that it helps maintain our sleep quality. In the evening, the body converts serotonin into melatonin to prepare us to go to bed. Because of this, having enough serotonin in the brain is necessary to fall — and stay — asleep.
Serotonin’s impact on the body isn’t just limited to brain function, though. Over 90% of the body’s serotonin is produced in the gut, where it has a protective effect. The health of our stomach and the balance of bacteria within impacts our stress resilience and immunity.
When we feel stressed, the body responds with the fight or flight response. The autonomic nervous system (ANS) controls this stress response. It also controls other involuntary functions, like digestion, heart rate, and respiration. That’s why we tend to feel emotions like fear, anger, and disgust in our stomachs. Serotonin helps to regulate autonomic functions in the central nervous system. So when our stomachs are happy, we tend to be happier too.
In 2019, the Baylor College of Medicine conducted a study on gut permeability and depression. They found that increased gut leakiness was associated with increases in both depression and stress response. They also found that gut leakiness triggered the immune response. The relationship between the stomach and the brain goes both ways — it’s bidirectional. Brogan summarizes it by saying, “Not only can our brains affect how our guts feel, but our gut can relay its state of calm or alarm to the nervous system and send those immune reactions up the vagus nerve to the brain.”
With the growing interest in uncovering the link between gut health and mood disorders, a new field has emerged. This new area of science, called nutritional psychology, studies dietary patterns to determine if mental health problems can be alleviated holistically.
Eating a healthy diet can help you feel better and more alert — and it can also be a valuable source of serotonin. Although foods don’t typically contain serotonin, they do contain tryptophan, folic acid, and B12. These are necessary for the body to synthesize serotonin.
Here are 14 foods that you may want to incorporate in a healthy, serotonin-friendly diet:
- Soy, tofu, and edamame
- Nuts, seeds, and legumes
- Whole grains
- Fatty fish like salmon and anchovies
- Sweet potatoes
- Fermented foods like kimchi, sauerkraut, and kombucha
Incorporating the right foods into your diet is important for your well-being, but so is avoiding the wrong foods. Evidence is starting to show that people prone to mental illness should be cautious about sugar consumption. SugarScience at the University of California San Francisco points to a long-term study published in 2017 that found clear links between excessive consumption of sugar and mood and increased likelihood of being diagnosed with depression. Holistic psychiatrist Dr. Kelly Brogan cautions that. ups and downs in your blood sugar levels “deprives the brain of important nutrients.” Sugar may also “create systemic inflammation,” dysregulate hormones, and trigger adrenal fatigue.
7 healthy eating tips for mental health
If you want to keep your mood up and your blood sugar steady, you’ll want to begin incorporating healthy eating habits into your routine. While some of them are about what you eat (of course), there’s more to staying healthy than counting calories.
Here are 7 tips to improve your nutrition and your mental health:
- Avoid processed snacks
Processed foods often have flavors or preservatives added to them to help them survive the freezing and shipping process. This often means higher amounts of fat, sodium, and added sugar. Swap out your processed snacks for nutrient-rich foods. Try a yogurt parfait or hummus and pita instead of candy and chips.
- Set a schedule
Plan your meals out in advance. While meal planning is a “thing,” you don’t have to go overboard. Simply take a glance at the day ahead and aim to eat something small every two to three hours. Eating small, healthy meals frequently will prevent your blood sugar from dropping (and your mood from going along with it).
- Drink enough water
If food is the fuel that keeps you going, then water is the oil that keeps everything running smoothly. Much like motor oil, water helps to keep your temperature regulated, clean out your system, and improve your performance. Without water, your body has a much harder time extracting micronutrients from food. Mild dehydration also results in cognitive impairment. This leaves your brain less capable of regulating serotonin.
- Balance your macros
The big three macronutrients are fat, protein, and carbohydrates. All of them (yes, even fat) are necessary for optimal functioning. Balancing your intake with healthy amounts of each will help ensure that you have steady energy throughout the day. If you’re unsure how to find the right combination or need specific advice, reach out to a nutritionist.
- Get some bacteria in the mix
Your stomach is full of bacteria, and that’s a good thing. Probiotics can be helpful in regulating your digestive health by giving those bacteria a boost. When the bacteria in your gut is balanced and thriving, digestion is smoother and more serotonin is produced. Try taking a daily probiotic or adding fermented foods to your diet.
- Avoid inflammatory foods
Certain foods are more likely to cause an inflammatory response. Processed and high-sodium foods are obvious culprits, but even healthy foods can be triggering. Tracking your diet and mental health can help you determine if you have any underlying food sensitivities. You can also ask your doctor for an allergy test.
- Don’t be too strict
Food tends to be a trigger for many people. Because it’s closely related to weight and body image, it’s easy to get pedantic about your nutritional intake. However, making yourself stressed over eating healthy all the time is a good way to undermine the actual benefits of eating well. Aim to make good food choices roughly 80% of the time. What you do every day is more important than what you do once in a while.
Of course, if you think about what you eat as fuel for your day, pay attention to how well your fuel is working. We all respond a little bit differently to what we put into our bodies. Keep a diary for a week to note what you eat and how you feel, both before and after. Noticing these patterns can be helpful both for motivating some dietary changes and understanding what changes might have the biggest impact for you.
There are scientific, social, and emotional factors that connect nutrition and brain health. Eating well helps you feel more clear headed and energetic. Your body is better able to produce serotonin, you’ll sleep better, and you’ll have more energy for what matters the most to you.
BetterUp Staff Writer