Before, after and after-after
There's nothing more inspirational to those trying to lose weight than a miracle slimming story. But many dieters end up putting it all back on.
The number of obese people in the world has topped 2.1 billion, while the UK authorities are changing their guidelines to emphasise the need to lose at least a small amount of weight but to keep it off for life.
"Yo-yo dieting" - or the losing and then regaining of weight - is both bad for health but also depressing for dieters. Many struggle to achieve a consistent weight loss over a long period.
Alexander Holland, from Didcot, says he has struggled with his weight for most of his adult life.
"In 2009 I reached 28 stone (177kg) and my doctor said that I needed to lose weight or risk an early death. Pretty motivating stuff, eh? Add to that my size was pretty socially unacceptable. I was 37 and single with no prospects of romance.
"The NHS offered me a gastric bypass at a cost to the taxpayer of approximately £15,000 for the operation plus £20,000 in after-care. Or £2,000 worth of diet pills. Or a maximum of £44-worth of fat club vouchers. I like to consider myself a socially responsible person so I took the diet club vouchers. I had never tried to diet before, but being a scientist I knew the formula. Less energy (calories) in than energy (exercise) out equals weight loss.
"I have absolutely zero willpower but I was able to create a diet which didn't really need any. It had to be enjoyable to taste, have similar portion sizes so I wasn't hungry and most importantly not take any longer to prepare and cook or generate any more washing up. If it had done either then I wouldn't have been able to stick to it.
"I also needed an incentive so I took a sponsorship. Lose 2lb per week and my sponsors pay to my charity. Don't lose 2lb and I pay their pledge. The pledges soon totalled over £50 per week.
"I joined the gym in December 2009 and did one hour of exercise per day, seven days per week, starting with swimming and then cycling and eventually running. By March 2010, I had lost 8 stone (50.8kg) - roughly 1 stone per month for eight months - and by October 2010 I had lost a total of 14 stone.
"The food was fun to eat, and I actually started to enjoy the exercise. So much so that when I reached my goal weight of 12 stone in March 2011, I kept exercising and ran the Oxford Half Marathon in 2011 and again in 2012.
"In October 2011, I met the girl of my dreams quite by accident. Ironically she is a head chef at a restaurant. Romance as a slim person comes freely and easily. Wish I'd known 20 years ago. It had taken me less than two years to lose 16 stone (102kg).
"But that isn't where the story ends. In February 2012 my mum died of cancer. It was an exceptionally emotional time for me and I gave up my regular exercising and went back to the comfort foods of takeaways and home-cook pizza. Fast forward to May 2014. In less than two years following the death of my mum I've put back on 8 stone.
"But it isn't rocket science. I know that I was able to do it before all it takes is pure honesty to yourself and a deep need to do it. Anyone sponsor me 50p per week?
Tash Harrison weighed 18 stone (114kg) in 2008. By June 2010, she had lost six stone. Now she weighs 15 stone 6lb.
"I've always been overweight, since I was about 10. When I got into my first relationship that seemed to put my weight up - possibly stress from it being a bad relationship. When I was single again I decided to focus on me. That's when I started going to the gym at least five times a week and eating very little.
"I lost about six stone in just over a year. At that point people were saying I was too thin. It's taken about five years but I've put a lot of that weight back on. I've joined a gym again but only lost a few pounds here and there.
"I don't think I'm as committed to losing weight as I was last time, and also I suffer from an overactive thyroid disorder which makes it hard to lose weight. My Body Mass Index (BMI) is 31 so that's in the obese category. I would like to change that but I'm finding it a struggle.
"I'm currently on a fast diet but I don't think I can stick to it. It only allows you 500 calories over two days, then you can have as much as you like to eat on the other five days. I would like to join another group but they are so expensive. I'm very much an emotional eater - if I'm upset about something I tend to binge on sweets and chocolate. It doesn't make me feel better though so I don't know why I do it. I think in the past I've made lots of excuses but the only person who can change my life is me - no-one else."
Psychologist Deanne Jade, who specialises in obesity and eating disorders, says it is normal for those dieting to subsequently put weight back on. A small minority of all overweight people find they can keep the weight off without any kind of therapeutic work to address their overeating, she says. But most can't.
"There are people who overeat in emotional contexts, whether the emotions are good or bad. You've got to work on helping them manage their emotions in a different way and adjust their mindset."