Have you ever been hangry (hungry + angry)? You’re certainly not alone. Your diet is a two-way street—food can affect your mood, and your mood can affect your food choices.1-4 This can be for better or for worse. Generally speaking, processed, deep-fried, or sugary products may raise your mood briefly, but then will cause your mood to sink. Whole plant-based foods, such as beans, fruits, and vegetables, as well as fish, may be a better bet when it comes to stabilizing or improving your mood long term.4,5 Understanding how your brain interacts with what you eat will help you make more informed decisions about your diet and avoid emotional or impulse eating.
SCIENCE BEHIND FOOD AND MOOD
The idea that eating wholesome, nutritious foods is conducive to brain health and a better mood may seem like a no-brainer, but, historically, nutrition research has focused largely on how the foods we eat affect our physical health, rather than our mental health.4,6 As researchers have investigated the food-mood relationship, they have discovered three major themes: the microbiome’s affect on mental health, certain foods’ effect on the quality and patterns of sleep, and the addictive properties of certain foods.
Gut microbiome. The connection between diet and emotions stems from the close relationship between your brain and your gut bacteria, often called the “second brain” or gut microbiome. What you eat affects your gut microbiome—a broad term that refers to the trillions of bacteria living in your gut.2-4 Your microbiome influences your body’s production of neurotransmitters—chemical messengers such as dopamine and serotonin—that directly influence your mood. For example, eating wholesome foods promotes the growth of “good bacteria,” which can boost your mood. On the other hand, highly processed foods high in added sugars and saturated fats offer the body (and the beneficial bacteria living in your gastrointestinal tract) little nutrition and can cause systemic inflammation that hampers the production of those neurotransmitters.2,4,7 In short, when neurotransmitter activity is in good shape, your brain receives those messages loud and clear, which allows a generally balanced emotional state. However, when neurotransmitter production goes awry, your mood may follow suit.6,8
Sleep. A growing body of research suggests that diet affects sleep quality, and sleep quality can affect diet.9-11 High-carbohydrate meals with high glycemic indices have been shown to negatively impact sleep quality.10 While high-carbohydrate meals can make you feel drowsy, they can also increase the number of times you wake up throughout the night and reduce the amount of quality sleep you receive.10 Research has also shown that sleep deprivation increases cravings for high-calorie, weight-promoting foods, resulting in increased risk for obesity in individuals who experience poor sleep.11 However, sleep and nutrition are both complex, which makes it challenging to conduct research that pinpoints which diet is best for sleep. Researchers are still not able to explain, for example, whether poor diet leads to poor sleep or poor sleep leads to poor diet.9,12 For now, studies can show only correlations between diet and sleep patterns.9
Addictive foods. Highly processed foods dominate the American diet, despite being linked to obesity, heart disease, Type 2 diabetes, cancer, and other chronic diseases. Not only are these foods cheap, convenient, and tasty—they may be addictive.13 Many experts argue that choosing to eat highly processed foods over whole foods goes beyond just giving in to temptation. For some people, processed foods, such as French fries, ice cream, and potato chips, can elicit “addictive-like” eating behaviors, such as intense cravings, a loss of control over eating, and an inability to cut back or eliminate them from the diet, despite experiencing harmful physical consequences or a strong desire to stop eating them.14,15 One study found that when people cut back on such foods, they experienced withdrawal symptoms comparable to those associated with drug withdrawal, such as irritability, fatigue, sadness, and cravings.15 Other experts argue that processed foods do not cause an altered state of mind, a hallmark of addictive substances.16 What is clear from both sides, however, is that eliminating ultra-processed foods from one’s diet can be difficult and, at least temporarily, can have a negative effect on mood.13-16
If you’re feeling down, it may be tempting to turn to food for comfort, but it’s important to keep in mind the effect that food can have on your mood and overall health and vice versa. Mood can be influenced by environment, stress, genetics, and diet. Old adages remain true: moderation is key, stay hydrated, and keep a balanced diet. New research about the relationship between food and mood will continue to emerge, shedding more light on this connection.
1. American Heart Association website. Food and mood. Updated 25 Jun 2018. https://www.heart.org/en/healthy-living/healthy-lifestyle/mental-health-and-wellbeing/food-and-mood. Accessed 3 Aug 2021.
2. Firth J, Gangwisch JE, Borsini A, et al. Food and mood: how do diet and nutrition affect mental wellbeing? BMJ. 2020;369:m2382.
3. Schiffman R. Can what we eat affect how we feel? 28 Mar 2019. New York Times website. https://www.nytimes.com/2019/03/28/well/eat/food-mood-depression-anxiety-nutrition-psychiatry.html. Accessed 3 Aug 2021.
4. O’Connor A. How food may improve your mood. 6 May 2021. New York Times website. https://www.nytimes.com/2021/05/06/well/eat/mental-health-food.html. Accessed 3 Aug 2021.
5. Harvard Health Publishing website. Food and mood: Is there a connection? 15 Feb 2021. https://www.health.harvard.edu/mind-and-mood/food-and-mood-is-there-a-connection. Accessed 3 Aug 2021.
6. Mujcic R, J Oswald A. Evolution of well-being and happiness after increases in consumption of fruit and vegetables. Am J Public Health. 2016;106(8):1504-1510.
7. Gomstyn A. Food for your mood: how what you eat affects your mental health. Aetna website. https://www.aetna.com/health-guide/food-affects-mental-health.html. Accessed 3 Aug 2021.
8. Nguyen TT, Zhang X, Tsung-Chin W, et al. Association of loneliness and wisdom with gut microbial diversity and composition: an exploratory study. Front Psychiatry. 2021;12;395.
9. O’Connor A. How foods may affect our sleep. Updated 1 Jan 2021. New York Times website. https://www.nytimes.com/2020/12/10/well/eat/sleep-foods-diet.html. Accessed 3 Aug 2021.
10. St-Onge MP, Mikic A, Pietrolungo CE. Effects of diet on sleep quality. Adv Nutr. 2016;7(5):938–949.
11. Greer SM, Goldstein AN, Walker MP. The impact of sleep deprivation on food desire in the human brain. Nat Commun. 2013; 4: 2259.
12. Lindseth G, Lindseth P, Thompson M. Nutritional effects on sleep. West J Nurs Res. 2013;35(4):497–513.
13. O’Connor A. Unhealthy foods aren’t just bad for you, they may also be addictive. 16 Feb 2021. New York Times website. https://www.nytimes.com/2021/02/18/well/eat/food-addiction-fat.html. Accessed 3 Aug 2021.
14. Schulte EM, Avena NM, Gearhardt AN. Which foods may be addictive? The roles of processing, fat content, and glycemic load. PLoS One. 2015;10(2):e0117959.
15. Gearhardt AN, Hebebrand J. The concept of “food addiction” helps inform the understanding of overeating and obesity: YES. Am J Clin Nutr. 2021;113(2):263-267.
16. Hebebrand J, Gearhardt AN. The concept of “food addiction” helps inform the understanding of overeating and obesity: NO. Am J Clin Nutr. 2021;113(2):268-273.