As daylight hours shorten and temperatures plummet, feelings of sadness and fatigue can begin. Depression is a major health concern that impacted 28 million people worldwide in 2019. In that same year, an estimated 10 million Americans experienced a specific type of depression disorder during the winter. Seasonal affective disorder (SAD) is a type of depression that is correlated to specific seasons like fall and winter, according to a study in Nutrients.
Chronic sadness, social withdrawal and difficulty concentrating, thoughts of death or suicide, changes in appetite, feeling listless or hopeless, anxiety and oversleeping, or reduced libido are all symptoms of SAD. While most cases begin in late fall or early winter, in rare cases, some people experience depressive symptoms during the spring and summer months – also known as summer-pattern SAD or summer depression.
Research on how to prevent and treat SAD is varied and while taking vitamin D may help symptoms, studies do not show consistent results in treating SAD. However, adding vitamin D to your diet, spending time outdoors, and consulting with a provider can help manage these symptoms.
Vitamin D in Foods and Supplements
Sun exposure allows our bodies to absorb vitamin D, which can help prevent and treat the symptoms of SAD, according to the International Journal of Pharmaceutical Sciences Review and Research. However, there is limited access to the sun during the winter season. By turning to certain dietary choices, we can still have access to this vital nutrient.
Tuna, salmon, and eggs are foods that are rich in vitamin D. In a recent study published in Nutrients, participants who received vitamin D intravenously experienced relief from depressive symptoms associated with SAD as compared to those who took a placebo. Adding foods rich in vitamin D to a diet is more reliable than store-bought supplements in addressing the symptoms of SAD, since research on vitamin D supplements does not provide consistent results.
Zinc and Depression
While zinc has not shown direct correlation with treating symptoms of SAD, it does have anti-depressant qualities. Zinc is an antioxidant that supports mental wellbeing, brain function, and reduces inflammation. Zinc deficiency is correlated to depressive symptoms, anxiety-like behaviors, and even higher suicidal ideation risk.
Zinc also has a synergistic relationship with vitamin D, acting as a cofactor for vitamin D functions and aids vitamin D to work inside human cells. Combining zinc and vitamin D has been shown to be more effective in decreasing depressive symptoms than vitamin D alone, according to Nutrition.
Inadequate levels of zinc may also lead to low gamma-aminobutyric (GABA) levels in the brain, because GABA is directly correlated to blocking signals of fear, stress, and worry, zinc supplementation can improve feelings of anxiousness.
More Research Is Needed
There is still more research needed to understand what can treat and prevent the symptoms of SAD. While focusing on nutrients can help, there is more to understand about mood disorders.
Recent studies show that carotenoids can potentially treat and prevent depression based on their antioxidant and anti-inflammatory qualities. Carotenoids are fat-soluble pigments that can be found in specific varieties of yellow, dark green, and red fruits and vegetables like kale, cantaloupe, bell peppers, and tomatoes.
Specifically, astaxanthin – a red carotenoid pigment that naturally occurs in marine life like algae – may be effective in treating psychiatric disorders, according to Frontiers in Pharmacology. While additional clinical trials are needed to understand the efficacy of astaxanthin on depressive symptoms in humans, initial studies in mice have been promising.
If you are struggling with SAD, be sure to consult with a provider first to understand the correct treatment for you.
Article Sources:
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Boston University. Seasonal Affective Disorder Impacts 10 Million Americans. Are You One of Them?
Johns Hopkins Medicine. Seasonal Affective Disorder
International Journal of Pharmaceutical Sciences Review and Research. The Potency of Natural Carotenoids as a UV-Skin Protection and Sunburn Prevention: Review
Scientific Reports. Zinc nutritional status, mood states and quality of life in diarrhea-predominant irritable bowel syndrome: a case–control study
Science Direct. Association between serum zinc levels and suicidal ideation in US adults: A population-based cross-sectional study
National Library of Medicine. Zinc and its role in vitamin D function
National Library of Medicine. The relationship of serum vitamin D and Zinc in a nationally representative sample of Iranian children and adolescents: The CASPIAN-III study
National Library of Medicine. Decreased Zinc and Increased Copper in Individuals with Anxiety
National Library of Medicine. Antioxidant and Anti-Inflammatory Effects of Carotenoids in Mood Disorders: An Overview
Frontiers in Pharmacology. Preventive and Therapeutic Effects of Astaxanthin on Depressive-Like Behaviors in High-Fat Diet and Streptozotocin-Treated Rats
National Library of Medicine. The antidepressant-like effect of trans-astaxanthin involves the serotonergic system
Science Direct. Trans-astaxanthin attenuates lipopolysaccharide-induced neuroinflammation and depressive-like behavior in mice
