In a former life, Dr David Hamilton built heart and cancer drugs by manipulating atoms; these days he shows people how to use their minds to heal their bodies - and vice versa.
A soft-spoken 44-year-old Scot, Hamilton spent years working in the pharmaceutical industry - his PhD was in organic chemistry, he explains, and his work essentially "involved sticking atoms together to make pharmaceutical drugs."
However the young chemist became increasingly conscious of an apparent mind-body link, which, he gradually came to realise, enabled the mind to help heal the body, and the body to help the mind overcome crippling mental health issues such as a lack of self-confidence.
In others words, Hamilton believes you can literally help to heal physical ailments by repeatedly 'thinking' yourself better and tackle mental health issues by routinely doing certain physical exercises.
It all started, he recalls, with his increasing awareness of some extraordinary statistics which were coming out of the pharmaceutical industry's drug research.
"Ideally from the point of view of a drug company, 80pc of those on a particular drug would get better and nobody on the placebo would get better.
"However, what you find is that between 40pc and 79pc of people were improving on the placebo in some cases also. That for me was so interesting!"
Hamilton started to wonder whether people could actually improve their own health by just believing they were getting an effective drug.
"Therefore," he recalls, "surely the thinking itself could help them improve?"
The important thing to know, says Hamilton, a native of Stirling and the author of eight books on self-help, is that the brain does not distinguish between whether you are doing something or whether you are only imagining doing it.
The other important thing is that you believe something will work.
The third thing you need to know is that repetition is key.
"One of the things I say to people is that if you are going to have an effect on the body, you have to visualise the same thing over and over.
"For example if it is someone with arthritis, imagine using sandpaper to gently clean the debris from the joints. Then imagine applying a coat of soft oil to replenish the oils that should be in the joint.
"Do that over the day and the week - they can visualise this for 15 minutes a day every day, five times a week for a month."
Try it, he suggests.
"A lot of people find a difference."
You have to believe it will work, so that when you are doing something that you believes works, over and over again, the brain actually thinks it's happening.
He is aware of cases, he says, where some arthritis patients have progressed from virtual immobility to being able to jog in the space of several weeks."
However, he emphasises, don't assume you no longer need your medicine or your doctor.
"Take the medicine - but use the mind as well," he advises.
Over the years he's collected hundreds of stories about people who have used the technique of visualisation, and over and over again, he says, the story is the same.
"I went into the medical and scientific journals to look for a scientific explanation and the cornerstone for me is that the brain does not distinguish between the real and the imaginary."
Take the issue of paracetamol, he says, referring to a study in which different groups of people got versions of aspirin - some packaged more expensively than others.
"The more expensive aspirin worked 25pc better than the cheap one and the only difference was in the way it was packaged."
Next he says, researchers gave one group of volunteers a placebo that looked like an expensive aspirin and another group a placebo that looked like a cheap aspirin.
"Both placebos worked and the expensive placebo worked 25pc better than the cheap one."
You don't need to have a first-class degree in visualisation to 'think' yourself better, he says.
"What's important is that you believe and make an effort to imagine," he says, even if you don't see the imagine in high-definition in your imagination.
"Just use your own way of imagining. Imagine your body becoming better and better. That, in a nutshell, is the technique I share with people - belief in that is important."
Now, to the body, and what it can do for the mind.
"What happens to your body when you feel stressed?" he asks.
Your shoulders and facial muscles tighten - they're wired to the emotional circuit of the brain, he explains.
However, while the muscles respond to how you feel, they can also influence how you feel.
Hamilton refers to research into primates, which showed that when the alpha male stands tall and adopts a pose that makes its appear extra large, it impresses and intimidates the other members in the group. The funny thing is though, it seems that the power pose actually makes the alpha male feel stronger too.
And, says Hamilton, now the author of eight books, it can do the same for you.
In a Harvard research project investigating the effect of the body on the brain, two groups of volunteers were told to adopt different poses for a period of two minutes.
One group was told to adopt a "power" pose. The other a "weak" or "victim" pose.
Researchers took saliva samples after the two minutes. The results were eye-opening.
The hormone in the body associated with confidence - testosterone - had spiked by 20pc in those who adopted the power pose. Tests on these volunteers also showed a 25pc reduction in the stress hormone, cortisol.
Tests on the 'weak' pose group showed their testosterone levels had ropped 10pc while they experienced a 15pc increase in their cortisol levels.
"Just the way you hold your body can affect the way you feel," observes Hamilton, who says the reason he researched the issue of self-esteem and wrote a book, I Heart Me, about it, is that he suffered from it.
"I realised that you can actually change how you feel by changing what you do with your body."
In a 2014 study by scientists at the University of Auckland, New Zealand, 74 participants were asked to sit in an upright or slumped position. They had their backs strapped with tape to ensure they maintained the posture. They were given a stressful task whereby they had to tell a panel why they were the best candidate for a hypothetical dream job.
"Those who sat in an upright position reported higher self-esteem than those who sat slumped.
"They also had more positive moods and lower fear - and, the scientists even noted - they used more positive words than those who sat slumped."
Researchers at the University of Alaska, in Anchorage, asked volunteers to look at photographs of people who were either smiling or frowning. Half of the volunteers were asked to simply look at the faces. The other half were asked to copy either the smile or the frown.
Immediately afterwards, their moods were assessed. Those who copied a smile enjoyed a more positive mood. Those who copied a frown felt less positive. Those who just looked felt no different.
"In these instances, it was the movement of the muscles of the face in way that the brain recognised was correlated with happiness that produced the more positive feelings," says Hamilton.
"Swinging our arms joyfully as we walk will elevate our mood, while slouching and staring at the ground will depress it.
"If you start to walk tall it will re-shape some of the circuits in your brain and make you feel better. Your mind can heal your body and your body can heal your mind.
"However, you have to consciously do it, you must not resist it and you cannot do it in a half-hearted way. It has to be something to which you are giving your full attention."
Dr David Hamilton, author of 'I Heart Me; The Science of Self Love' will be one of the main speakers at the Mind Body Spirit and Yoga Festival in the RDS, Dublin, from March 14-16, where he'll give a two-hour workshop.
Health & Living