An analysis of 21 studies published in 2017 in Psychiatry Research concluded that a diet rich in fruit, vegetables, whole grains, fish, olive oil, dairy, and antioxidants was associated with a decreased risk of depression, while a diet high in refined grains, sweets, processed meat, and low intakes of fruit and vegetables was associated with an increased risk of depression. One study found that people who eat a lot of junk food were 51 percent more likely to develop depression compared to those who rarely ate junk food. And studies that have compared traditional diets, such as the Mediterranean diet or traditional Japanese diet, to the standard American diet (high in sugar, trans fats, and processed grains, and woefully short on veggies) have found that the risk of depression is 25 to 35 percent lower in people who eat a more traditional diet.
Another phrase we’ve all heard a thousand times: Eat the rainbow! It’s hard to stress just how important fruit and veggies are for mental health, so I’ll let the research speak for itself. Studies investigating fruit and vegetable intake and depression risk have consistently found that lower intakes are related to a higher risk of depression. Two recent studies reported that higher dietary intake of antioxidants was associated with lower prevalence of depressive symptoms, and a study published earlier this year found that eating a diet rich in fruit and vegetables was associated with less stress across all age groups. The researchers wrote, “We found that people who have higher fruit and veggie intakes are less stressed than those with lower intakes, which suggests diet plays a key role in mental wellbeing.”
Chronic inflammation and oxidative stress are both drivers of depression and other mood disorders, and fruit and vegetables are chock-full of antioxidants that reduce oxidative damage and inflammation. Fresh produce is also a wonderful source of fiber and prebiotics, which help maintain a healthy population of beneficial bacteria in the gut, and we know that gut health is directly related to mental health. For example, about 95 percent of our serotonin (a feel-good neurotransmitter) is produced in our guts and is strongly influenced by the types of bacteria there. Having a healthy gut makes you more resilient to mood disorders.
There is also a simple joy to be found in eating fresh fruits and vegetables (organic, of course!). A recent Australian study found that people who previously ate almost no fresh produce who began to eat fruit and vegetables daily reported an increase in life satisfaction and happiness equivalent to what an unemployed person feels after finding work. Another study from Germany found similar results, reporting that eating vegetables led to a higher level of happiness over time compared to junk foods. Among 14 different food categories, eating vegetables “contributed to the largest share of eating happiness.”
Our brains are 60 percent fat, and they need fat to thrive. Indeed, research shows that low-fat diets significantly increase the risk of depression, irritability, and anger. For example, one long-term study that included more than 12,000 people assessed over a 10-year period found that women on a low-fat diet were 37 percent more likely to be depressed after one year than women who did not eat a low-fat diet. Another study included 20 people (10 men and 10 women between 20 and 37 years old) who ate a high-fat diet for one month and had their moods measured by researchers. Half the participants were then switched to a low-fat diet while the other half continued to eat a high-fat diet. After another month, the researchers measured mood again and found that the people on the low-fat diet had become significantly more angry, hostile, and depressed while those that remained on the high-fat diet were less hostile, tense, and anxious (it is interesting to note that there were also no significant changes found in total or LDL cholesterol levels in the high-fat group).
Our brains need fat, but they need the right kinds of fats. The omega-3 fats EPA and DHA found in cold-water fatty fish like salmon, sardines, and tuna, and 100% grassfed beef and bison are particularly important for mental health and are backed by a large body of research showing their benefits in depression and other mood disorders. Saturated and monounsaturated fats are other types of healthy fats; look for them in coconut oil, dairy and butter from grass-fed animals, pasture-raised eggs, nuts and seeds, avocados, and olive oil.
Our bodies are intricate machines, with lots of working parts, so it makes sense that the better the fuel, the better the performance. Think of highly processed foods and sugar like dirty burning fuel—it clogs up and slows down the machinery. Research has shown that people who eat trans fats, even in small amounts, have an increased risk of depression (these types of chemically altered fats are commonly found in fast food, fried food, commercial baked goods, and many processed foods). The same goes for sugar, with research showing a correlation between sugar intake and increased risk of depression, ADHD symptoms, bipolar disorder, and aggressive behavior. Work on replacing processed and sugary foods and drinks in your diet with nutrient-dense foods, focusing on colorful fruits and vegetables and healthy fats. One easy way to do this is to minimize the number of meals you eat out and make more meals at home (naturalgrocers.com/recipes is full of healthy and delicious recipes to stoke your creativity in the kitchen). And if you occasionally enjoy a burger and fries or pizza, don’t sweat it! As long as you’re eating healthy most of the time, your brain can handle these occasional indulgences.
Supplements can help fill in some of the nutritional gaps of a poor diet, but they are not a substitute for healthy eating; it’s important to work toward improving your diet, in addition to taking supportive nutritional supplements. When you are eating well, supplements can go the extra mile to support your mental wellness.
B-Complex. The B vitamins are involved in healthy neurotransmitter production, a healthy stress response, and are necessary for normal central nervous system function. Low levels of thiamin (B1), folic acid, B6, and B12 have been implicated in an increased risk of depression. Sixty days of supplementation with a B-complex has been shown to significantly improve depression and anxiety symptoms and overall mental health in people with depression. Look for a high-potency B-complex.
Magnesium. Known as a calming mineral, much of the population consumes inadequate amounts of magnesium, and mental and emotional stress quickly deplete levels. Sometimes called the original “chill pill,” magnesium plays important roles in the nervous system, including modulating the hypothalamic-pituitary-adrenal (HPA) axis, our central stress response system. A study published in 2017 found that supplementation with 248 mg of elemental magnesium for six weeks resulted in a “clinically significant” improvement in depression scores among 126 moderately depressed adults. The positive effects were observed within two weeks. After the six-week trial, depression scores dropped on average by six points, from moderately depressed to mildly or minimally depressed. Anxiety scores also improved. Try 400 mg of magnesium daily.
EPA & DHA. Scores of studies have shown that EPA and DHA reduce the risk of depression, anxiety, impulsivity, and aggressiveness. These fats help the transmission of neurotransmitters, reduce levels of the stress hormone cortisol, reduce inflammation, and have been found to be significantly lower in people with depression compared to those without depression. Cold-water fatty fish are the best food sources of these important omega-3s, which means most of us don’t consume enough. Try 2 to 4 grams of combined EPA and DHA in fish oils daily.
Phosphatidylserine (PS). This phospholipid (a type of fat) is critical for maintaining brain cell health, keeping our brain cell membranes strong and fluid, allowing them to communicate with ease. It also helps protect brain cells from the negative effects of stress, helps repair damaged cell membranes, and modulates the HPA axis, blunting the body’s hormonal stress response. Clinical research has found that PS supplements reduce the cortisol response to both mental and physical stress and can improve mood, including helping symptoms of depression and anxiety. Try 300 mg of PS daily.
Big dietary changes can be challenging. For support and guidance on your journey to healthier eating, consider making an appointment with your local Natural Grocers Nutritional Health Coach (NHC).