So what happened to transform the 40-something mum of three into a dynamic businesswoman who loves nothing better than to stand in a room full of people, right at the front, sharing her passion for healthy living?
"I find it bizarre that I now get up at 5.30am every day, juggle work and family life and weigh less than I did in my 20s," says Debbie, a chiropractor with her own specialist family clinic in Harrogate.
Running a successful business has been a confidence booster in itself but the big change came three years ago when Debbie decided to go back to the classroom and train as a wellness chiropractor. She qualified in 2009 and is now one of only four certified chiropractic wellness practitioners in the UK.
"Like everyone else, I've dieted and worked out in gyms, struggling with weight problems, but in the end it was just a case of changing my mental attitude. Dieting and endless forced gym workouts can be a frantic paddle upstream and are doomed to fail as you lose the strength to keep paddling and drift back to the start."
Debbie believes our bodies are programmed to be well, fit and healthy. If this is not how you feel, it is because your body is being forced to adapt to lifestyle stressors you are placing on it.
"These stressors occur in how we eat, move and think or, put another way, the physical, chemical or emotional issues in your life. Toxicity and deficiency in these key areas are at the root of all chronic illness.
"I believe our bodies are the most amazing machine on this planet; they are fine-tuned to respond to everything they could encounter in the natural world. However, they are not programmed to respond to the artificial, chemical, toxic environment we now exist in.
"If we can educate ourselves to know what we can and cannot deal with, we will have a chance at a happy, healthy, illness-free life.
"All I had to change was my belief system. I had to be open-minded enough to let someone talk to me about another way, another view, and then I made my own mind up. After that, it was easy, it was so easy."
As well as incorporating her lifestyle expertise into her chiropractic work, Debbie has written a guide to help people make long-term changes to their behaviour and health.
"I had intended to write a book but I realised that most people read the first chapter with great enthusiasm and never reach the end, leaving the book to gather dust along with good intentions and New Year resolutions."
Debbie split the guide into 12 monthly issues, each encouraging small changes to diet, exercise and attitude in the hope that these will be easy to stick to.
Her aim is to give people the information they need to make better choices but never to force them to eliminate anything, particularly if it's something they enjoy.
"It may sound too good to be true but when you live a healthy lifestyle it's still possible to treat yourself and when you do, make sure you really enjoy it."
Debbie says she has transformed her own life through diet, exercise and a positive attitude and she is now determined to help others do the same.
"All our behaviour is led by our belief systems. Once you believe differently, your behaviour naturally becomes different and the change that follows is effortless.
"My work is far from over, and I dream of inspiring and educating many more people to make life-saving changes to their lifestyles," says Debbie.
The Complete Lifestyle Guide is available at www.completelifestyle.co.uk. A 12-month subscription costs 22.90.
debbie's top tips for big meals
Start with something fresh and raw.
Choose smaller plates, especially for the main course.
Ensure that 50 per cent of your plate is covered with vegetables.
Remember you only need 2oz of protein a day, so don't overdo the meat.
Don't drink water through the meal.
Chew your food thoroughly.
Put your knife and fork down between mouthfuls – don't keep shovelling.
Leave 20 minutes between courses.
Do not continue to eat if you feel full.