Depression is a mood associated with hopelessness and inadequacy that almost everyone will feel at least once in their lifetime. Clinical depression, however, is where the individual has such a depressed mood for such a prolonged period of time that it begins interfering with their normal life. Clinical depression can range from mild to severe.
The prevalence of clinical major depressive disorder for a lifetime is approximately 24% in the U.S.,1 meaning that in the U.S., there is a 24% percent chance that you will get clinical depression at some point in your life. Of course, there are many variables that would increase the risk of this happening, such as being socially, financially, and educationally disadvantaged, or having had a major event in life, such as a death of someone close, divorce, or even having had a traumatic event in childhood. You may have clinical depression if you can relate to the following:
Depression doesn’t have one specific cause; environmental and genetic factors may be at play, as well as psychosocial stressors, however, a major factor causing depression is unhealthy dietary factors. Fast-food and commercial baked goods are linked to depression in a dose dependent manner,2 and dietary excellence can be the solution for many suffering individuals. A feeling of a depressed mood can also be a symptom of other medical conditions or a side effect from a medication, so to be sure of what is causing your symptoms, you may need to discuss your depression with your doctor.
Tsuboi H, Shimoi K, Kinae N, et al. Depressive symptoms are independently correlated with lipid peroxidation in a female population: comparison with vitamins and carotenoids. J Psychosom Res 2004, 56:53-58. doi: 10.1016/S0022-3999(03)00567-1
Dias GP, Cavegn N, Nix A, et al. The role of dietary polyphenols on adult hippocampal neurogenesis: molecular mechanisms and behavioural effects on depression and anxiety. Oxid Med Cell Longev 2012, 2012:541971. doi: 10.1155/2012/541971
Nabavi SM, Daglia M, Braidy N, Nabavi SF. Natural products, micronutrients, and nutraceuticals for the treatment of depression: A short review. Nutr Neurosci 2017, 20:180-194. doi: 10.1080/1028415X.2015.1103461
Hritcu L, Ionita R, Postu PA, et al. Antidepressant Flavonoids and Their Relationship with Oxidative Stress. Oxid Med Cell Longev 2017, 2017:5762172. doi: 10.1155/2017/5762172
Spencer JP. Flavonoids and brain health: multiple effects underpinned by common mechanisms. Genes Nutr 2009, 4:243-250. doi: 10.1007/s12263-009-0136-3
Lai JS, Hiles S, Bisquera A, et al. A systematic review and meta-analysis of dietary patterns and depression in community-dwelling adults. Am J Clin Nutr 2014, 99:181-197. doi: 10.3945/ajcn.113.069880
Beezhold BL, Johnston CS, Daigle DR. Vegetarian diets are associated with healthy mood states: a cross-sectional study in Seventh Day Adventist adults. Nutrition Journal 2010, 9:26. doi: 10.1186/1475-2891-9-26
Blanchflower DG, Oswald AJ, Stewart-Brown S. Is Psychological Well-Being Linked to the Consumption of Fruit and Vegetables? Social Indicators Research 2012. doi:
Beezhold BL, Johnston CS. Restriction of meat, fish, and poultry in omnivores improves mood: A pilot randomized controlled trial. Nutr J 2012, 11:9. doi: 10.1186/1475-2891-11-9
Francis HM, Stevenson RJ, Chambers JR, et al. A brief diet intervention can reduce symptoms of depression in young adults - A randomised controlled trial. PLoS One 2019, 14:e0222768. doi: 10.1371/journal.pone.0222768
Molendijk M, Molero P, Ortuno Sanchez-Pedreno F, et al. Diet quality and depression risk: A systematic review and dose-response meta-analysis of prospective studies. J Affect Disord 2018, 226:346-354. doi: 10.1016/j.jad.2017.09.022
Sanchez-Villegas A, Toledo E, de Irala J, et al. Fast-food and commercial baked goods consumption and the risk of depression. Public Health Nutr 2012, 15:424-432. doi: 10.1017/S1368980011001856
Mocking RJ, Harmsen I, Assies J, et al. Meta-analysis and meta-regression of omega-3 polyunsaturated fatty acid supplementation for major depressive disorder. Transl Psychiatry 2016, 6:e756. doi: 10.1038/tp.2016.29
Shafiee M, Arekhi S, Omranzadeh A, Sahebkar A. Saffron in the treatment of depression, anxiety and other mental disorders: Current evidence and potential mechanisms of action. J Affect Disord 2018, 227:330-337. doi: 10.1016/j.jad.2017.11.020
Lopresti AL, Drummond PD. Saffron (Crocus sativus) for depression: a systematic review of clinical studies and examination of underlying antidepressant mechanisms of action. Hum Psychopharmacol 2014, 29:517-527. doi: 10.1002/hup.2434
Hausenblas HA, Saha D, Dubyak PJ, Anton SD. Saffron (Crocus sativus L.) and major depressive disorder: a meta-analysis of randomized clinical trials. J Integr Med 2013, 11:377-383. doi: 10.3736/jintegrmed2013056
Khazdair MR, Boskabady MH, Hosseini M, et al. The effects of Crocus sativus (saffron) and its constituents on nervous system: A review. Avicenna J Phytomed 2015, 5:376-391. doi:
Shaw K, Turner J, Del Mar C. Tryptophan and 5-hydroxytryptophan for depression. Cochrane Database Syst Rev 2002:CD003198. doi: 10.1002/14651858.CD003198
Galizia I, Oldani L, Macritchie K, et al. S-adenosyl methionine (SAMe) for depression in adults. Cochrane Database Syst Rev 2016, 10:CD011286. doi: 10.1002/14651858.CD011286.pub2
Mischoulon D, Fava M. Role of S-adenosyl-L-methionine in the treatment of depression: a review of the evidence. Am J Clin Nutr 2002, 76:1158S-1161S. doi:
Williams AL, Girard C, Jui D, et al. S-adenosylmethionine (SAMe) as treatment for depression: a systematic review. Clin Invest Med 2005, 28:132-139. doi:
Nahas R, Sheikh O. Complementary and alternative medicine for the treatment of major depressive disorder. Canadian Family Physician 2011, 57:659-663. doi:
Schuch FB, Vancampfort D, Richards J, et al. Exercise as a treatment for depression: A meta-analysis adjusting for publication bias. J Psychiatr Res 2016, 77:42-51. doi: 10.1016/j.jpsychires.2016.02.023
Cooney GM, Dwan K, Greig CA, et al. Exercise for depression. Cochrane Database Syst Rev 2013:CD004366. doi: 10.1002/14651858.CD004366.pub6
The following are sample questions from the Ask the Doctor Community Platinum and higher members can post their health questions directly to Dr. Fuhrman. (All members can browse questions and answers.)
I’ve read several articles that state that gluten sensitivity may cause depression. Is that true? I’ve experienced depression and fatigue for years. I would have thought losing 70 pounds would have given me more energy but it hasn’t. Do you think I should try a gluten free elimination diet? If so, how long would it take for me to know if gluten is a problem for me?
Even though depression and fatigue are both on the list of possible symptoms one can have if they are sensitive to gluten and eating it, the high glycemic diet with white flour and sugar is a much more likely factor. We have to be careful not to assume that one is sensitive, though, just because they have these problems. Sometimes people will notice that they feel the effects of foods such as grains and fruits that can cause a rise in blood sugar quicker than other foods, which can include somewhat of a withdrawal effect resulting in perhaps fatigue or depression as well as other possible symptoms, but that isn’t the case for most people. Change your entire diet to a Nutritarian diet with the proper supplements I recommend to aid your mood. Utilize light therapy too, as that is an effective intervention. Your diet then will already be low in gluten anyway, but if you don’t see a significant improvement in a few months, a trial off gluten is reasonable.
Is there any real evidence that refined sugar contributes significantly to depression, such as scientific studies? I know that the physical body suffers tremendously from sugar consumption, but I would like to know if it really affects mood and how.
Yes, oxidative stress in general, which means low intake of the broad spectrum of plant-derived phytochemicals can also contribute to depression. Also, Vitamin D deficiency and omega-3 deficiencies can also contribute. I’ve also included a study for your review, and, yes it is also true that sugar, fast food, and commercially baked goods are linked in scientific research to depression. For example, in this study published in Public Health Nutrition, those who ate more fast food or commercially baked goods had double the risk of depression.
My son seems to be depressed lately. He doesn’t stay focused and sits around a lot and watches TV. He is 31 and married with a one-year-old. He is also 30 pounds overweight. He gets interested in eating and exercising and then day 2 - stops. Can eating healthy help with this, or should he go to a doctor and get evaluated? Most doctors will just put him on anti-depressants or Ritalin. What do you think?
A standard American diet is deficient in nutrients that foster optimal brain health. Low levels of nutrients like zinc, omega-3 fats, vitamin D, and folate, to name a few, are linked to depression and ADHD. Plus, medical studies reveal poor nutrition, junk food, and commercially baked goods are a causative factor. Given his weight, he likely has insulin resistance and other hormone imbalances that are associated with mood and behavior disorders. So, eating a high nutrient dense diet along with a few important supplements is critical to his mental wellbeing.
How does taking omega-3’s help with depression or other mental issues?
There are many theories on the mechanism of why high dose omega-3 fatty acids improve depressive symptoms, but we do know that it does help and has some kind of mood stabilizing effect. The dose of the EPA ingredient should be fairly high to maximize speed of onset. Most studies recommend 1,000 mg of the EPA component daily, but I do not think that high a dose should be maintained forever. After a few months, cut back to about half that amount.
I am a 58-year-old female and very overweight. I am at the point where I am thinking of getting on some meds for depression and anxiety. I only have the energy and motivation to get myself to work, have clean clothes for work, and just do what I must. I decreased my hours at work, hoping I would then have more time and energy to eat healthy, but the lack of inner mobility is really making it difficult to do what is needed to purchase, prepare, eat, and then clean up after a meal.
I found someone to help and he suggested some amino acids that may help, but I would like to run this by someone. Question- Is it harmful to take 5HTP, Tyrosine and DHA? Would there be any side effects?
I know if I can stick with this plan for six weeks, I would get rid of my food addictions and feel better emotionally, but I know I need to feel better emotionally so that I can stick with this. I have felt slightly depressed most of my life, but the past 4-6 months have been more so. I had been on psych meds before, and they helped a little.
I am sorry you are having this trouble, but your best chance to really get well emotionally is to eat well. Looking to medicate to be able to eat well is a pie in the sky expectation. You have to eat well whether you feel like it or not, and then you will eventually feel well. A Nutritarian diet, without excuses, can help solve your problems. Hundreds of people have noted their mood elevated after switching to this way of eating, and it is established in medical studies that fast food and commercial baked goods are a causative factor in depression. 5-HTP can be helpful for some people, but others have increased anxiety with it. Tyrosine can also cause anxiety and sleep disturbances, particularly if taken later in the day. Depression and anxiety is usually helped more with EPA/DHA, as omega-3 fatty acid deficiency is associated with mood disorders. Use a purified fish oil, and take at least 600 mg of the EPA component each day. You also should make sure you are taking Vitamin D3 to get your 25 hydroxy vitamin D level between 30-50 ng/ml.
Try to get out early in the morning to walk in the sunshine. Have you considered light therapy? It is very effective. Try to include 15 minutes of light therapy every morning at 7:00 sharp.
Exercise every day. Exercise has been shown to reduce depression, and combined with the light therapy, it should be more effective than anti-depressants, regardless of your diet. Try using meditation CDs at night to help reduce your stress. Taking saffron can also help.
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