Retired Banker Ian Gourlay has taken part in eight nutrition studies at the Rowett Institute and is shortly to embark on his ninth.
The 56-year-old, from Bridge of Don, said being a volunteer had improved his awareness of his own health - and in one weight loss study he shed more than a stone in just eight weeks.
Ian first became involved three years ago after reading an article in the Press and Journal about recruitment for a carbohydrate study.
“I was coming up to retirement and I thought it sounded interesting,” he said. “I started on the longest study I've yet to volunteer for - an eight week trial investigating whether ready meals specially designed to ensure you feel fuller for longer could help weight loss.
“I was provided with all the food and we were asked to keep our intake to 2,000 calories a day by keeping a food diary. In that particular study I managed to lose a stone which was a real bonus.”
Since then he's gone on to take part in studies investigating everything from the benefit of beetroot in burgers to the importance of fruit and vegetables and the brassica family of vegetables in our diets.
Mr Gourlay said he was pleased to know he is playing his part in furthering knowledge of health and nutrition.
“In my late 40s I was 15 stone and totally unfit so I decided I was going to start going to the gym and created a 'get fit for 50 campaign' for myself,” he added.
“I now try to keep my weight around 13 stone but having struggled to control it in the past I really appreciate how important this type of nutrition research is and I've been more than happy to help by volunteering for studies I'm suitable for.
“When I worked in banking I enjoyed being able to help the customers, now I know I am helping scientists to achieve their research goals.
“On a personal level it has also been useful in making me more aware of my overall health. I get my blood pressure checked regularly and I know my cholesterol and glucose levels, as well as my resting heartbeat.
“That's a real benefit as unless you are ill you don't tend to be tested regularly for these things.
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