Inflammation causes depression?

Posted on January 18, 2012


Old Man in Sorrow (On the Threshold of Eternity) by Vincent Van Gogh (via Wikimedia Commons)

Dateline: 4 December 2011 // Posted by: Claire Mc Callion (@ClaireMcCallion)

Source: Huffington Post

Story: “Inflammation causes depression?”

Summary: This article by Dr Andrew Weil was recently published on the widely read news blog ‘The Huffington Post’. Dr Weil’s website quotes itself as being ‘the premier resource for timely, trustworthy information on natural health and wellness, based on the insights of Andrew Weil, M.D’. He is reporting here that there is a correlation between depression and inflammation. The ‘depression epidemic’ as Dr Weil calls it, he believes is not only due to ‘disease-mongering by pharmaceutical companies’ but is also down to ‘cytokines’. Apparently cytokines are quite powerful. The interleukins control inflammation and fever, and ‘another type’ of cytokines controls how the red and white blood cells in the bone marrow mature. In the eighties a new treatment involving interferon was developed as a as treatment for different types of illness such as cancer and autoimmune disease.

A commonly-reported side effect of interferon therapy is severe depression. When interferon is tested on animals, they have been shown to elicit ‘sickness behaviour’ such as listlessness and losing interest in eating, sex, and show increased sensitivity to pain, these characteristics are changes noticeably similar to humans that suffer from depression. Increased inflammation being used as a tool to treat another illness may help but it has quite extreme side effects.

He also suggests an ‘anti-inflammatory diet’ to help cure and reduce inflammation.

Why is this PseudoNews? It can be argued that this article contains a number of pseudoscientific claims. Weil suggests that ‘a commonly-reported side effect of interferon therapy is severe depression; in fact, some patients have committed suicide’. He does not offer us any evidence to support this claim. According to scientific research carried out by the Portland Veterans Affairs Medical Centre, ‘the majority of patients (who took interferon) developed at least some symptoms of depression and 33 percent met criteria for major depression’. They did however also say that not only is interferon ‘the most effective drug against the life-threatening liver disease and hepatitis C’ but also that 84% of the people who developed depression could be treated by taking a mild anti-depressant (and for those whose mental state didn’t improve, it was ‘the usual and customary practice to take patients off interferon if they become depressed’).

Weil appears to make little of some very serious illnesses. My favourite quote of the entire article is ‘People with rheumatoid arthritis, scleroderma, systemic lupus (SLE) and other forms of autoimmunity are often depressed’ because of the inflammation that they get from their illness. This can be true for many other reasons other than inflammation. A recent study done by Robbins et. al found that depression in elderly people with rheumatoid arthritis wasn’t linked with medication, such as interferon, but was linked with pain.

The final and perhaps the most worrying aspect of the article is that Weil suggests a change in diet could cure all of the problems mentioned. If this is true then by his reasoning eating ‘organic lightly cooked dark greens’ should cure a swollen ankle. However if depression is caused by inflammation, could it not also be cured by some over the counter anti-inflammatory such as ibuprofen?

What features of pseudoscience are on show? There are many different features if pseudoscience in this article. There is a heavy use of vague, exaggerated and untestable claims. Weil repeatedly uses quite complicated words without explaining them. The claim of ‘aggressive disease-mongering by pharmaceutical companies’ is a very dangerous one and is much exaggerated. He does not mention other factors such as the economic downturn, which could be causing an increase in depression. According the Samaritans there has been a vast difference in the suicide rates from 2007- 2010. They however do not include inflammation in their statistics report.

Another blatantly obvious pseudoscientific feature of this article is a distinct over-reliance on confirmation rather than refutation. A true scientific study will not only research why it is correct but also why it could be wrong. He states that dietary choices are the most important factor in keeping inflammation in check. Genuine scientific studies also never refer to the personal ‘I’.  He is putting his own ideas forward as facts, without the back up of any data.

The moral of the story: False information like the type supplied in this article could cause people to chose unreliable medical advice (to which even highly intelligent and successful people such as Steve Jobs are susceptible), and therefore could have a very negative effect on their health.