Turmeric, botanical name Curcuma longa, has been used for thousands of years as a medicinal herb. It has been used traditionally in countries such as India, China and Thailand for conditions as varied as poor digestion, skin conditions, jaundice, insect bites, fevers, sprains, arthritis and gastrointestinal ulcers.
There have been thousands of studies investigating the many health benefits of turmeric. Recent studies have been focusing on possible anti- depressant effects of turmeric via the chemical constituent curcuma.
Brain derived neurotrophic factor (BDNF) is a protein that promotes the development of, aids in the survival of and improves the function of neurons. Studies have shown that there is a decreased number of BDNF in people with major depression and that there is cellular atrophy (shrinkage) and increased neuronal death. One of the ways that anti depressant medications treat depression is by increasing BDNF.
An area being currently researched is the ability of curcumin to increase BDNF. Research published in the Journal of Behavioural Brain Research in 2013 reported that “This data provides evidence for an antidepressant-like effect of curcumin, possibly through increased neurotrophic activity …” Another study published in Phytotherapy Research in 2014 concluded there was “… clinical evidence that curcumin may be used as an effective and safe modality for treatment in patients with MDD (Major Depressive Disorder)…”
In another recent study, published in 2015, 111 subjects with a major depressive disorder were either given anti depressant medication alone or together with curcumin. Their level of depression was measured using the Hospital Anxiety and Depression Scale (HADS). The study concluded “There were significantly greater reductions in total HADS score and subscales of anxiety and depression in the curcuminoids versus control group.”
Another way that turmeric can help with depression is by regulating serotonin and dopamine in the brain. Depression is a very complex condition and there are often many contributing factors, but an imbalance in the neurotransmitters serotonin and dopamine is commonly found in depressed people. According to a study published in the Indian Journal of Pharmaceutical Sciences in 2010, “Curcumin also modulates various neurotransmitter levels in the brain.” They concluded that “… curcumin possessed multiple actions in brain. Curcumin can be a future drug of therapy for the treatment of various neurological disorders such as major depression …”
Turmeric has powerful anti inflammatory properties and inflammation is another major contributing factor to depression. When there is chronic low grade inflammation in the body the amino acid tryptophan, which is a precursor to serotonin, is diverted away from producing serotonin, potentially leaving low levels of serotonin which in turn can lead to depression.
A study published in March 2015 in Jama Psychiatry investigated whether or not inflammation was a major driver of depression. They used positron emission tomography (PET) to scan the brains of 20 depressed patients and 20 healthy control subjects. The scans showed significant inflammation in the brains of the depressed patients. The more severe the depression, the more severe the inflammation was. The clinically depressed patients had 30% higher brain inflammation than the control group.
In 2013 researchers at Aarhus University, Denmark examined the health records of almost 3.6 million people. They discovered that those people who had increased inflammation caused by conditions such as Rheumatoid Arthritis or Crohn’s disease (both autoimmune conditions) were 45% more likely to suffer from depression. They also discovered that people were 62% more likely to develop depression if they had been hospitalised for a serious inflammatory infection such as hepatitis or sepsis.
Oxidative stress has also been linked to depression, another indication that turmeric could have anti depressant properties. Turmeric is not only a powerful antioxidant, but it stimulates the body to produce glutathione, the “mother of all antioxidants”.
A 2013 meta-analysis published in Psychoneuroendocrinology concluded that oxidative stress “… is increased in depression.” In 2014, another meta-analysis observed “… an association between depression and oxidative stress and antioxidant status across many different studies.”
There have also been studies that have shown no anti-depressant effects of curcumin. In reading these studies, it is important to note that the bioavailability of curcumin is very poor so when analysing studies on the efficacy of curcumin in depression, it needs to be understood that if the dosage given to the participants is too low, there will not be enough of the active constituents to have an effect.
While the very convincing research continues, turmeric is promising to be another exciting alternative for treating depression. It must be noted that there are many contributing factors that lead to depression, and it is important to remember that the holistic approach to health is essential in treating any condition. Never stop taking medication for depression without first consulting with your Doctor and do not self prescribe.
A qualified Naturopath experienced in mental health is skilled at gaining insight into the “whole picture” of your depression and prescribing appropriate supplements that are relevant to your individual needs.
By Andrea Southern, Naturopath, Nutritionist, Herbalist Stafford and The Gap in Brisbane. For an appointment phone 0412 791 705