Omega-3

• In 2009 CNS Neuroscience & Therapeutics published a review of 3 studies involving a total of 60 patients which tested the effects of Omega-3 fatty acids on individuals with depression. In all 3 studies Omega-3 fatty acids were more effective than a placebo in treating depression in both adults and children. [Source]
• In 2014 the Public Library of Science published a meta-analysis of 19 studies which found omega-3 PUFA (polyunsaturated fatty acids) to be effective in treating both patients with MDD (major depressive disorder) and patients with symptoms of depression but no diagnosis of MDD. [Source]
• In 2014 the American Journal of Therapeutics published a study in which 40 dialysis patients with depression were given either 6 soft-gels totaling 1080 mg EPA and 720 mg DHA or a placebo daily for 4 months. The results showed health-related quality of life and depression scores improved significantly in the Omega-3 group compared to the placebo group. [Source]
• In 2007 The Journal of Clinical Psychiatry published a meta-analysis of 10 studies involving patients with mood disorders receiving omega-3 fatty acids for 4 weeks or longer. The data showed significant improvement in patients with clearly defined depression or bipolar disorder. [Source]
• In 2012 The Journal of Clinical Psychiatry published a meta-analysis of 5 studies involving 291 subjects which found omega-3 supplementation to have a moderate effect on bipolar depression. [Source]

Exercise

• In 2005 the American Journal of Preventative Medicine published a study which tested the effects of different levels of exercise on mild-to-moderate depression. The result was a significant 47 percent reduction in depression scores for individuals in the higher-dose exercise group of 17.5-kcal/kg/week (which correlates to about 1200 calories burned per week for a 150 lb person). [Source]
• In 2014 the Journal of Science and Medicine in Sport published a meta-analysis of 5 trails published since 2007. The data showed that moderate intensity aerobic exercise performed 3 times weekly for a minimum of 9 weeks can be used to treat depression. [Source]
• In 2016 the Journal of Psychiatric Research published a study which examined 25 clinical trials which compared exercise to control groups. The data strongly supports exercise as an evidence-based treatment for depression. The largest effects were seen for moderate intensity aerobic exercise. [Source]
• In 2016 the Journal of Affective Disorders published a meta-analysis of 23 studies involving 977 participants which found that exercise could be a useful treatment for depression when used with antidepressants. [Source]
• In 2000 Psychosomatic Medicine published a 4-month study involving 156 adults with MDD (major depressive disorder) in which individuals were assigned to an exercise program, sertaline (brand name Zoloft) therapy or a combination of both. While all three groups showed significant improvement, after 10 months the exercise group had significantly lower relapse rates than the medication group. [Source]
• In 2011 Psychosomatic Medicine published a 4-month study involving 202 sedentary adults in which individuals were assigned to either supervised exercise, home-based exercise, sertaline or a placebo. The results showed that aerobic exercise had a similar effect to sertaline after 4 months of treatment. One year after completion regular exercise was predictor of remission rates, with 180 minutes of exercise per week corresponding to lower rates of remission. [Source]

Vitamin D Deficiency

• In 2017 the Journal of Affective Disorders published a review of which found that empirical studies provide increasing evidence of a link between vitamin D deficiency and depression as well as the use of vitamin D supplementation for clinically depressed individuals with vitamin D deficiency. [Source]
• In 2013 The British Journal of Psychiatry published a meta-analysis of 13 studies and 31,424 participants which found that individuals with the lowest levels of vitamin D had significantly higher rates of depression than those with the highest levels of vitamin D. [Source]
• In 2012 The British Journal of Psychiatry published a 6-month, placebo-controlled trial which tested the effects of 40,000 IU of vitamin D taken weekly on individuals with low serum vitamin D. Individuals with low levels of vitamin D were found to be more depressed when compared to a control group with high serum vitamin D, though no significant effect of vitamin D supplementation was seen when compared to a placebo. [Source]
• In 2014 Molecular Psychiatry published an observational study involving 2,386 subjects which indicated that low levels of vitamin D correlated with increased rates of depression greater symptom severity. [Source]
• In 2013 Clinical Interventions in Aging published a study which included 1618 patients aged 60 or older at a primary care facility. The data showed that those with a severe vitamin D deficiency were twice as likely to have depression. [Source]
•  In 2011 Mayo Clinic Proceedings published a study based on 12,594 patients seen from 2006 to 2010. The sample showed that higher vitamin D levels were associated with a significantly decreased risk for depression. [Source]
• In 2010 International Archives of Medicine published a study based on data from a national health survey of 7970 individuals which showed that sufficient levels of vitamin D significantly were associated with a reduced likelihood of depression. [Source]
• In 2014 The Australian and New Zealand Journal of Psychiatry published a study of 735 subjects which found an association between serum vitamin D levels and depression in males, but not in females. [Source]

Vitamin D Supplementation

• In 2014 Nutrients published a meta-analysis including 15 clinical trials in which the researchers found a significant improvement in depression with vitamin D supplementation – comparable to that of an anti-depressant medication. [Source]
• In 2012 Acta Paediatrica published a study in which 48 depressed adolescents with depression were given vitamin D over a 3 month period. The data showed as serum vitamin D levels increased well-being increased and there was a significant improvement in 8 of 9 items on the vitamin D deficiency scale including depressed feeling, irritability, tiredness, mood swings, sleep difficulties, weakness, ability to concentrate and pain. [Source]
• In 2008 the Journal of Internal Medicine published a trial in which 441 participants were given 20,000 or 40000 IU of vitamin D per week or a placebo. After one year there was a significant improvement in depression scores in both vitamin D groups, but not the placebo group. [Source]
•  In 2015 Nutrition published a meta-analysis of 9 trials including a total of 4923 participants. The data showed that there was no reduction in depression seen after vitamin D supplementation, however most of the studies included focused on individuals with low levels of depression and sufficient vitamin D levels at baseline. The authors recommend further studies focused on depressed individuals who are deficient in vitamin D. [Source]
• In 2013 the Journal of Clinical Psychopharmacology published a study involving 120 patients which investigated the effect of 2 single-dose vitamin D injections of 150,000 and 300,000 IU compared to a control group. The 300,000 IU dose, but not the 150,000 IU dose, improved depression compared to the control group. [Source]
• In 2014 Psychosomatic Medicine published a meta-analysis of 7 trials involving 3191 participants which found that vitamin D supplementation had a positive effect on clinically significant depression, but only a small non-significant effect on individuals without clinically significant depression. [Source]

Vitamin B12

• In 2013 The Open Neurology Journal published a study in which 73 patients (who responded inadequately to the first trial with the SSRIs) with low-normal B12 levels were assigned to vitamin B12 injections and antidepressants or antidepressants alone. Results showed that after 3 months vitamin B12 combined with an antidepressant was more effective than an antidepressant alone in improving depressive symptoms. [Source]

B Complex

• In 2013 ISRN Psychiatry published a double-blind, placebo-controlled trial in which 60 adults with major depression or other depressive disorders were assigned a B complex vitamin or a placebo. The B complex group saw significant improvements in depression, metal health and mood at 30- and 60-day follow-ups when compared to a placebo. [Source]

Gluten Free

• In 2014 Alimentary Pharmacology and Therapeutics published a double-blind, cross-over study in which 22 patients with IBS (irritable bowel syndrome) linked to non-celiac gluten sensitivity were found to have increased feelings of depression when placed on a gluten-containing diet for a 3-day period. [Source]

Sleep Duration

• In 2015 Depression and Anxiety published a meta-analysis of 7 studies involving 48,934 subjects which found that sleeping less than normal was associated with a 31 percent increased risk of depression and sleeping longer than normal was associated with a 42 percent increased risk of depression. [Source]

Diet

• In 2015 The American Journal of Clinical Nutrition published a study which found that high GI (glycemic-index) diets, including sugars and refined grains, were associated with a higher risk of depression in postmenopausal women. [Source]
• In 2010 The Australian and New Zealand Journal of Psychiatry published a study based on questionnaires completed by 7114 Australian adolescents ages 10-14. The researchers found that diet quality was associated with adolescent depression above and beyond potential confounding factors. [Source]
• In 2014 The American Journal of Clinical Nutrition published a meta-analysis of 13 observational studies which found that a healthy diet high in fruit, vegetables, fish and whole grains was associated with a significantly reduced risk of depression. [Source]
• In 2010 The American Journal of Psychiatry published a study of 1046 women which found that “western” diets high in fried foods, refined grains, sugar and beer were associated with higher levels of depression and mental disorders. [Source]
• In 2014 Brain, Behavior and Immunity published a study in which 43,685 women filled out dietary questionnaires. After a 12-year follow-up the data showed that diets associated with inflammation were also associated with an increased risk for depression. [Source]

Fast Food

• In 2012 Public Health Nutrition published a study based on 8,964 participants which found a greater risk of depression was associated with higher levels of fast food consumption. [Source]
• In 2016 Maternal and Child Health Journal published a study involving 332 subjects which found that fast food intake was linked to depression in overweight, pregnant women. [Source]
• In 2011 Preventative Medicine published a study based on a questionnaire of 626 women aged 45-54. The results showed, after adjusting for confounding factors, women with depressive symptoms had a 54 percentage greater chance of reporting higher fast food intake. [Source]

Nutritional Deficiencies

• In 2008 the Indian Journal of Psychiatry published a review which noted that the most common nutritional deficiencies in patients with mental disorders include omega 3 fatty acids, B vitamins, minerals and amino acids. [Source]

Sedentary

• In 2015 the British Journal of Sports Medicine published a meta-analysis including 24 studies and a total of 193,166 patients which found a that sedentary behavior is associated with an increased risk of depression. [Source]