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Thursday, 28 March 2013

Placebos? Over-excitement can be a side effect

Placebos are in the news lately. Doctors are confessing to prescribing inert medicines. New and intriguing research is published indicating that placebos may work, even when the patients know they are inert. And a pharmaceutical company has patented a new, and questionable, way of conducting placebo-controlled trials (see links below).
Doctors may approve of the placebo effect because the patient’s symptoms may improve without the need for expensive drugs.
Alternative practitioners usually approve because the benefits of their methods seem to rely heavily on the placebo effect.
Psychologists love them because, well, they are intrinsically fascinating. Why should pills of different colours induce different degrees of placebo effect? Such phenomena are fascinating in the extreme.
Drug companies are not so keen on them, because all too often their shiny new products fail to work significantly better than the placebos used in trials.
And the rest of us may think they are a “good thing” because, lets face it, we’d all like to think that positive thinking of one kind or another can bring about miraculous cures.
But the existence of the placebo effect is no reason to get carried away. And completely carried away some folks do seem to be when they argue thus:
1.    The placebo effect exists, therefore your mind can control your body.
2.    The placebo effect is a kind of positive thinking
3.     Therefore my kind of positive thinking can cure cancer, AIDS and other serious diseases.
Fortunes have been made selling books and conducting lectures along these lines but there are a few flaws in the argument, lurking beneath that therefore like ants, teeming beneath a stone.
Firstly, not everyone is susceptible to the placebo effect. In any controlled experiment, some subjects who have received a placebo will report they feel much better. While others report no improvement. It is not a consistent or predictable effect – not in the least.
Secondly, the placebo effect may alleviate symptoms, but nothing more. It may bring about less pain, less nausea, better mood, that kind of thing. These are symptoms, not diseases. It does not work as a method of shrinking cancers, curing for AIDS or repairing damaged heart muscle.
If you read the “miracle cure” literature it is sprinkled with “case studies” – or rather, anecdotes, in which people claim that their methods have cured serious illnesses. But they offer no research to back these claims.
So we should not get over-excited about the placebo effect. It may have its uses in the control of symptoms, but panacea it is not.

Thursday, 7 March 2013

Undercover Inflammation?

There is increasing mention of the word inflammation these days - in relation to diabetes for instance. Put the word into Google and you get 66 million hits. Many of them will be talking in alarmist terms, claiming that inflammation causes nearly every worrying disease you can think of. They go on to recommend anti-inflammatory diets or supplements. It's a typical sales pitch: create concern; convince customers they have a need and then offer a solution.
But scientists also seem interested in chronic inflammation, so what is behind this increasing interest?
Inflammation is the emergency response of the immune system. If you scratch your hand in the garden, within 24 hours it will be red and swollen. Around the scratch, tissues are flooded with fluid. This contains a potent mix of immune chemicals whose main role is to disable bacteria by attaching themselves, in a kind of chemical rugby tackle. They will also send out an alarm call to millions of immune cells (white blood cells). When they arrive on site they destroy the immobilised bacteria. Within a couple of days the redness and swelling is subsiding and the inflammation starts to disappear as the immune system stands down. Inflammation is nature's way of protecting the body against bacterial invasion and it saves lives on a routine basis.
The problem comes when there is inflammation without any invading bacteria.
Unwanted inflammation can cause damage to healthy tissues. In the absence of an enemy, the troops (the immune cells and chemicals) start picking a fight with the civilians. A vivid demonstration of this is seen in rheumatoid arthritis in which inflammation gradually causes permanent damage to a joint. 
Recent research has been unpicking the complex links between obesity and raised levels of inflammation chemicals in the body. These chemicals are referred to a “inflammatory markers” in research papers.
When someone gains weight, they don’t grow more fat cells. Instead, their fat cells store more and more fat, like balloons filling with water. When they get to a certain size they start to trigger tiny amounts of inflammation. This may be because they start to leak, or start interacting with immune cells in abnormal ways. Recent research has revealed that they can even start behaving a bit like immune cells when they become over-filled with fat. The net result is that there are more inflammation-related chemicals sloshing around the body than you would want. These chemicals can cause slow and subtle damage to tissues and play their part in chronic diseases. They are a link in the chain between increased body fat and the increased risk of heart disease and diabetes.
There is lots of research going on into the exact mechanisms. This is fascinating for those involved but the immune system is unimaginably complicated and therefore difficult to tweak. Science is unlikely to come up with any miraculous, seise-effect-free drugs that will protect obese people from diabetes and heart disease.
If you are overweight and concerned about your health then pills and potions will not “reduce inflammation”. They will just waste your money and make supplement sellers rich. The solution, I'm afraid is to eat a better diet, lose weight and shrink those fat cells.

"Obesity makes fat cells act like they’re infected." Science Daily article.