The Importance of Assessing Nutritional Status in Depression
Introduction
As the seasons start to change and we see the transition in the weather from bright and long summer days to the shorter and darker days of winter, many start to notice a shift in their mood. This is often associated with varying degrees of seasonal affective disorder (SAD) but many face the burden of sadness, hopelessness, lack of pleasure, disturbed sleep patterns associated with depression all year long. These symptoms vary in severity and in more severe cases can lead to suicidal ideation and self-harming behaviours. With the strange and unprecedented times we are living in in the year 2020, it’s no doubt that many are plagued with many of these symptoms. 
Although depression is thought to have a multifactorial etiology, a common thought is that it is a brain-based issue relating to an imbalance in neurotransmitters such as serotonin, norepinephrine, GABA, and dopamine. This is certainly an important factor at play that is worth exploring. However, there is emerging research that is now investigating the role that gut health plays in the gut-brain axis. The gut-brain connection is really a two-way street of communication, with the gut often being referred to as our second brain. In fact, it is suspected that approximately 90% of your serotonin is actually made in the gut (1). Therefore, when trying to treat mental health concerns such as depression or simply supporting one’s mental wellness overall, it is vital to address gut healing as part of the treatment.
Gut healing is such an important foundation of health for so many health conditions, especially mental wellness. Many who suffer from symptoms of depression often are also diagnosed with gut issues such as leaky gut syndrome. An important first step is to find out about your individualized food sensitivities whether through an IgG Food Sensitivity Test (FST) or by conducting an elimination diet. By eliminating these foods from your daily intake, you can help to bring down the level of inflammation in your body. In addition to this, another important aspect of supporting your mental wellness is to assess any possible underlying nutritional deficiencies you may have. Many of these have been linked with depression and other health concerns.
B Vitamins
A B complex is a great adjunct or first-line treatment option to address depression. This supplement includes all of the B vitamins, namely vitamin B6, folic acid and vitamin B12. Specifically, low folate status, especially in women, has been correlated with higher rates of depression (2) (3) (4). Supplementation in conjunction with conventional medications increased the treatment response in those with major depressive disorder (MDD) (5) (6) (7). Folic acid supplementation was also assessed in those with a high familial risk of mental health concerns and although it did not prevent the onset of mood disorders altogether, it significantly delayed the onset from 5 to 15.5 months compared to placebo (8). In combination with vitamin B12 supplementation with folic acid over a long-term, showed a significant decrease in the risk of relapse (9). In general, a B complex is a great supplement as it can lead to an immediate positive impact on mood and energy, especially in patients with suboptimal levels (9).
Iron
Iron is a crucial component in the production of serotonin, which is a neurotransmitter that is greatly responsible for overall happiness and wellbeing (9). Therefore, it can be such a crucial supplement to support mental wellness in those who are deficient, which tends to be women of reproductive age. There is a strong correlation between anemia and depression and this actually shows a dose-dependent relationship where the lower the hemoglobin levels, the more severe the symptoms of depression (9).
Vitamin D
There is no doubt that all of us living in Canada are susceptible to have deficient or suboptimal levels of vitamin D, especially as we transition away from the summer weather. Our decreasing exposure to sunlight, increases our risk of depressive symptoms such as low mood. Increased serum levels of vitamin D has been associated with a 43% decrease in the risk of depression and panic disorder, especially in more susceptible populations including adolescents, the obese population, and perinatal mothers (9). In these cases and more, supplementation is often recommended as both a prevention and treatment approach to depression.
Omega-3s
Fish oil supplementation is another common go-to natural health strategy to address depression. As inflammation is being explored more in the world of research as another contributing factor to mental illness, a study demonstrated that those with higher levels of high sensitivity C-reactive protein (hs-CRP), an important marker of inflammation, are more likely to respond to fish oil supplementation in their treatment of depression (9). In particular, a fish oil with at least 60% EPA, or a 2:1 ratio of EPA:DHA, is preferred to leverage its powerful anti-inflammatory effects (10) (11) (12). It appears that supplementation with EPA helps to decrease symptoms of major depressive disorder in a dose-dependent manner (12). It’s notable beneficial effect appears to be comparable to some pharmaceutical first-line medications such as fluoxetine (sold under the brand Prozac), a selective serotonin reuptake inhibitor (SSRI) (13).
Zinc
Zinc for the Think! The hippocampus is the part of the brain that is responsible for emotion, memory and motivation (9). Interestingly, the hippocampus is one of the body parts with the highest concentration of zinc (9). When this mineral is present at higher levels usually from increased dietary intake from foods such as seafood, beef and lamb, green leafy vegetables and nuts and seeds, there is an associated decrease in the incidence of depression (14) (15). Scores of depression also improved in patients with major depressive disorder after supplementing for about 3 months (16) (17).
In conclusion, we cannot deny the importance of a well-rounded healthy and balanced diet to support our mental wellbeing in our everyday lives. Nutrition is such a vital component to support the gut-brain axis. Focus on including plenty of plant-based foods such as fruits and vegetables of all colours, and eliminating the more inflammatory foods such as gluten, dairy, and sugar. Following a Mediterranean-based diet can also be beneficial as one study showed a 32% rate of remission in patients with moderate to severe depression compared to only 8% in the control group (9). Whether using this as a first-line approach or as a complimentary approach to medication, ensuring optimal nutritional status is vital.
