Research & Education

New Research: Low Intake of Fruits & Veggies Linked to Depression

According to a recent article published in BMC Psychiatry, a lower intake of fresh fruits and vegetables was found to be associated with depression in both middle-aged and older men and women.

The results demonstrated that women who had low fruit and vegetable intake and increased fruit juice, chocolate, or salty snack consumption predicted a higher likelihood of depression. On the other hand, there was a lower likelihood of depression in men who consumed higher fat and omega-3s, as well as moderate vegetables and fruits, in addition to foods with calcium and vitamin D. According to the study, the anti-inflammatory and antioxidant compounds in vegetables and fruits were considered to be the reason consuming more of these foods was shown to be protective against depression. Researchers note that the magnesium, zinc, and selenium in vegetables and fruits may help reduce C-reactive protein, an inflammatory biomarker associated with depression.

Depression is a major cause of disease burden worldwide, affecting more than 350 million people. And although there are numerous medications that are formulated to treat depression, less than 50% of patients with depression actually take them. According to the present study, “depression was associated with having chronic pain and at least one chronic health condition for both men and women,” underlining the importance of the connection between mind and body. 

There are many factors at play when it comes to depression and mental illness. Biological, psychological, and social determinants are associated with depression and must be addressed in order to figure out the root cause of those who suffer from such a debilitating disorder. It is well-known in research that nutrition (the foods that we eat on a regular basis) absolutely contributes to our overall health, in particular our mental health, yet is often overlooked for its role in preserving brain health. It is well-established that there is a strong association between gut health, brain function and mood, known as the gut-brain-axis. While depression and stress may wreak havoc on GI function, problems within the GI tract, such as intestinal dysbiosis, can negatively impact the brain, which may lead to mood disorders.

Research shows that there is a variety of nutritional and lifestyle interventions that may help prevent and/or reduce depressive symptoms without succumbing to antidepressant medications (which may cause potential adverse effects and nutrient depletions). A published double-blind, RCT showed supplemental omega-3 fatty acids significantly reduced depression and body weight compared with the placebo group, which is very hopeful considering obesity and depression often coexist. A study published in the European Journal of Nutrition found that higher red blood cell concentrations of EPA and DHA are associated with a decrease in depressive symptoms as they influence cell membrane fluidity and have been shown to mitigate oxidative stress and inflammation, which are both associated with depression.

There is no denying that physical activity is essential for supporting mental health, but overtraining without getting adequate rest and nutritional replenishment may cause negative effects on the brain and mental health. In addition to vitamin R (rest & relaxation), daily probiotic supplements that increase microbial diversity may positively impact patients’ moods and decrease depressive symptoms. There are many other vitamins, minerals, and herbs that have been shown to have mood-stabilizing effects such as B-complex vitamins, zinc, inositol, St. John’s Wort (Hypericum performatum), Rhodiola rosea, and lavender. In a review published in Nutrients, researchers investigated the effects of B vitamin supplementation on mood, depression, anxiety, and stress and found significant improvement in overall mood and stress levels.

Although individual dietary supplements show promising results, it is important to keep in mind the importance of – and synergistic effects of – eating a diverse whole food diet that is rich in colorful vegetables and fruits, as the micronutrients work together in ways that science has yet to fully understand, all of which plays a significant role in patients who are dealing with depression and other mood disorders.   

By: Caitlin Higgins, MS, CNS, LDN