4 Supplements for Depression: Do They Really Work?
Major depressive disorder (MDD) affects nearly 14.8 million Americans over the age of 18.  This equates to nearly one in fourteen adults. The average age of depressive onset is 32. Obviously though, depression can develop at any age.
Depression is more prevalent in women than in men.  This ratio is a surprising 2:1, and transcends ethnicity, economic status or race.
Related: 3 Supplements for Anxiety - Kava, Ashwagandha & Theanine
For individuals under 18, one in eight adolescents and one in thirty-three children experience clinical depression. Late life depression is also common. Around six million elderly individuals experience some form of melancholy, while only 10% seek treatment.  It should also be noted that 58% of family members providing care for an aging relative are likely to show signs of depression.
While depression is mentally debilitating, it often impacts physical health and can coincide with other major medical conditions. Here is a breakdown:
- Those with depression are four times more likely to have a heart attack over the course of their life. Depressive individuals are also more likely to have a second heart attack, often with fatal consequences.
- 25% of cancer patients experience depression.
- Up to 27% of individuals recovering from a stroke experience depression.
- 33% of folks that survive a heart attack experience depression.
- 33% of HIV patients experience depression.
- 50% of those with Parkinson's experience depression.
- Individuals with eating disorders such as bulimia and anorexia are extremely likely to experience depression, with a rate around 50 to 75%.
- 27% of those struggling with substance abuse also face issues with depression.
- SSRIs - Selective serotonin reuptake inhibitors. These include Zoloft, Prozac, Lexapro, Brintellix, Luvox, Celexa, Paxil, and Viibryd.
- SNRIs - Selective serotonin and norepinephrine inhibitors (SNRIs). These include Cymbalta, Pristiq, Effexor, Khedezla, and Fetzima.
- Noradrenergic Tetracyclic Antidepressants - Including certain NaSSAs, or serotonergic antidepressants, such as Remeron.
- Tricyclic Antidepressants - These include Sinequan, Imipramine, Elavil, and Pamelor.
- MAOIs - Monoamine oxidase inhibitors including Parnate, Emsam, and Nardil.
Natural treatments are also available. These supplements, or supplement ingredients, are not a replacement for medication, but they may prove to be beneficial. Please consult with your physician regard these supplements for depression.
Do Supplement for Depression Really Work?These are many supplement ingredients on the market that are touted as being beneficial for the treatment of depression, But do they actually work? That's the question.
Let's take a look at come popular supplements used to treat depression, and find out which are worthy of consideration.
#1 - Fish OilClick here to order the best-selling Ethitech fish oil.
There are a substantial number of studies revealing that fish oil supplementation may be beneficial for the treatment of depression. It should be noted that data hints that fish oil yields benefit to those that are majorly depressed. An insignificant amount of evidence exists to back fish oil as a treatment for minor depressive conditions.
Benefits have been shown to be similar to pharmaceutical drugs such as fluoxetine, but again, only for those diagnosed with major depressive disorder. Here are a few noteworthy results.
- 2.5g of fish oil was shown to reduce the level of anxiety by 20%, but showed no important impact on depression. 
- A meta-analysis of clinical trials revealed that EPA, not DHA, provided a significant antidepressant effect. Optimal daily dose was 1,000mgs per day. 
- 8 weeks of EPA (2,200mg) and DHA (1,200mg) appeared to reduce symptoms of depression compared to a placebo. 
#2 - 5-HTP and TryptophanTryptophan is a precursor to 5-HTP. Deficiencies in tryptophan are associated with depression. Low tryptophan levels can be caused by diet, or by upregulation of enzymes such as tryptophan 2,3-dioxygenase (TDO) or indoleamine 2,3-dioxygenase (IDO) which can degrade tryptophan or reduce its likelihood of being synthesized.
Supplementing with tryptophan or 5-HTP may provide a slight advantage in the battle versus depression, but a meta-analysis of studies on this subject lacked statistical significance. 
Use of 5-HTP alone shows promise, but only when taken alongside other compounds that assist to augment its efficacy. One study combined 5-HTP with Carbidopa, a peripheral decarboxylase inhibitor.  The results were promising.
It should be noted that 5-HTP is marketed heavily as a natural remedy against depression. A meta-analysis on its effectiveness revealed that only 2 of 100 studies on 5-HTP and depression met solid scientific practices. 
The jury is still out on the impact of 5-HTP supplementation on depression. More studies need to be performed.
Found in green tea, the amino acid derivative theanine helps to trigger the release of GABA in the brain. GABA is responsible for activating neurotransmitters that promote a sense of calm and relaxation.
#3 - TheanineFound in green tea, the amino acid derivative theanine helps to trigger the release of GABA (gamma-aminobutyric acid) in the brain. GABA is responsible for activating neurotransmitters that promote a sense of calm, relaxation, and may assist with a decrease in anxiety.
Individuals with high baseline anxiety levels are most likely to see benefits from theanine supplementation.  While the impact of theanine on depression is debatable, it has been shown to help relieve anxiety.
- A daily 400mg of theanine has been shown to help with anxiety for those diagnosed with schizophrenia. 
- Theanine supplementation was shown to help with relaxation. 
#4 - Vitamin DA supervitamin known to promote bone health, vitamin D also shows promise in the battle versus depression and anxiety.
A recent double-blinded, randomized study revealed a decrease in depressive symptoms for those with MDD, or major depressive disorder.  A 2008 study focusing on 441 obese individuals found that 20,000 to 40,000 IUs of vitamin D per week reduced the symptoms associated with depression over the course of a year. 
In 1979 a correlation between lower vitamin D intake and higher signs of depression was reported.  One study that analyzed depressive in adolescents noted a 42% reduction in symptoms following three months of increased vitamin D intake. 
Final ThoughtsThose with symptoms of severe depression should seek assistance as soon as possible. Ask your mental health care professional about natural supplements for depression and anxiety.
Fish oil, theanine, and vitamin D are relatively inexpensive, and certainly worth consideration. The jury on 5-HTP supplementation is still out, but this does not rule out the possibility that it may yield benefits.
References1) "Depression Statistics - Depression and Bipolar Support Alliance." Depression & Bipolar Support Alliance - Depression and Bipolar Support Alliance. N.p., n.d. Web. 22 July 2016.
2) Journal of the American Medical Association, 2003; Jun 18; 289(23): 3095-105
3) "Omega-3 Supplementation Lowers Inflammation and Anxiety in Medical Students: a Randomized Controlled Trial. - PubMed - NCBI." National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
4) "EPA but Not DHA Appears to Be Responsible for the Efficacy of Omega-3 Long Chain Polyunsaturated Fatty Acid Supplementation in Depression: Evidence... - PubMed - NCBI." National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
5) "Omega-3 Fatty Acids for Major Depressive Disorder During Pregnancy: Results from a Randomized, Double-blind, Placebo-controlled Trial. - PubMed - NCBI." National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
6) Shaw K, Turner J, Del Mar C Are tryptophan and 5-hydroxytryptophan effective treatments for depression? A meta-analysis . Aust N Z J Psychiatry. (2002)
7) van Hiele LJ l-5-Hydroxytryptophan in depression: the first substitution therapy in psychiatry? The treatment of 99 out-patients with 'therapy-resistant' depressions . Neuropsychobiology. (1980)
8) "Are Tryptophan and 5-hydroxytryptophan Effective Treatments for Depression? A Meta-analysis. - PubMed - NCBI." National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
9) "KoreaMed - Basic Search." KoreaMed - Basic Search. N.p., n.d. Web. 22 July 2016.
10) "Effects of L-theanine on Attention and Reaction Time Response." ScienceDirect.com | Science, Health and Medical Journals, Full Text Articles and Books. N.p., n.d. Web. 22 July 2016.
11) "NCBI - WWW Error Blocked Diagnostic." NCBI - WWW Error Blocked Diagnostic. N.p., n.d. Web. 22 July 2016.
12) "The Acute Effects of L-theanine in Comparison with Alprazolam on Anticipatory Anxiety in Humans - UQ ESpace." Home - UQ ESpace. N.p., n.d. Web. 22 July 2016.
13) "Vitamin D Supplementation Affects the Beck Depression Inventory, Insulin Resistance, and Biomarkers of Oxidative Stress in Patients with Major Depr... - PubMed - NCBI."National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
14) "Effects of Vitamin D Supplementation on Symptoms of Depression in Overweight and Obese Subjects: Randomized Double Blind Trial. - PubMed - NCBI." National Center for Biotechnology Information. N.p., n.d. Web. 22 July 2016.
15) Bech P, Hey H Depression or asthenia related to metabolic disturbances in obese patients after intestinal bypass surgery. Acta Psychiatr Scand. (1979)
16) Högberg G, et al Depressed adolescents in a case-series were low in vitamin D and depression was ameliorated by vitamin D supplementation . Acta Paediatr. (2012)