A placebo is often used in the trial of new medical treatments. It is an “empty” pill. It has no medicinal power. Half the sample receive the placebo and half the drug to be tested. Unfortunately for the drug companies, it has been known for a long time that, a placebo works. In Latin placebo means “I shall please”. They do make us feel better. Recent research has shown that this is not an illusion. It is not about susceptible people who do not have the disease.

The impact of a placebo can be measured in our physiology. In many trials some people who take a placebo show similar effects to those taking the “real” medicine. Blood pressure, heart rate and even blood tests all change. Brain scans show that a placebo creates real changes.

How does a Placebo Work?

An interesting effect has been found in the USA. The power of the placebo seems to be growing. Researchers looked at over 80 drug trials for nerve pain from all over the world. Over time an increasing number Americans are becoming susceptible to a placebo.

Not everybody is susceptible to a placebo. Surprisingly 12-15% of people in studies of anti-depressants respond to a placebo. 15% of patients in Parkinsons Disease studies show a placebo effect. So far no one has succeeded in explaining why. It is about expectations. Studies show that it depends on conditioning. How much an individual believes in the drug. How much they trust their doctor.

The placebo effect works best for illnesses that can be influenced by the brain. If you expect something to work, it is more likely to do so. One explanation suggested for the growing US power of the placebo effect use this idea. This is one of the few countries where consumer advertising for prescription drugs is allowed. Those advertisements stress the effectiveness of the drug. They raise the expectation of success. Certainly, placebo injections seem to be more powerful than pills. Do we expect them to be more powerful?

Expectations do not need to be in the form of a pill. We have all taken an eye test. The letters start large at the top and get progressively smaller. At some point we “fail”. We can no longer read the letters in the next line. In an experiment the chart was reversed. We start with the smallest letters, and they get bigger as we go down the page. At some point we succeed. We can read the next line. What the study showed was that we do better in the “success” version. We can read a line with smaller letters.

The Nocebo

The placebo has an evil twin. Nocebo means “I shall harm” in Latin. The nocebo effect can be just as powerful as its twin. If we expect something to do us harm it will do. We are told that a particular drug causes headaches as a side effect. We will get them even if taking a placebo. Even the words used by a doctor can become a placebo or a nocebo.

Every year we have a cold or two. We know the symptoms, the runny nose, sore throat and fever. We take our paracetamol and may or may not take to our beds. It goes away and we declare victory. We have beaten it. ( At least until it comes back next year). Cancer is different. The word itself causes fear and dread. Today many cancers are treatable and curable. We go through the treatment. Have our chemotherapy (drugs) and it goes away. Do the doctors congratulate us on winning. No, they say we are in "remission"(1). A temporary suppression. How long does remission have to last before it is declared a cure?

The Nocebo of Ageing

If we do not accept the artificial separation of mind and body, what does it tell us about ageing? In last week’s Newsletter, I described an experiment that literally reversed ageing. 80-year-olds felt and looked younger because they had spent a week living their youth. They were stronger mentally and physically. I also demonstrated the power of expectations. Describing work as exercise produced the same effect as exercise. Weight was lost, muscles built, and blood pressure reduced.

We know that our attitude to ageing affects our health and mortality. Ageism is therefore a Nocebo. It can destroy a positive attitude to our age. Ellen Langer asks why “change with age” is described in different ways. The mental and physical changes as we grow from a child to an adult are described as “development”. We change all our lives. We evolve to fit our environment and roles. At some point, however those changes stop being development and become “ageing”.

Remember Mark Twain who said:

Age is an issue of mind over matter

If you don’t mind it doesn’t matter

(1) Example from Ellen Langer.