An 18-year-old has described how miserable her life was before she had a gastric band fitted so she could undergo a dramatic weight loss to get her health under control.
Sadie Roberts told Good Morning Britain she was depressed, weighed 24 stone and at risk of diabetes before she had the drastic operation.
However, she defended her decision to have the surgery after it emerged "hundreds" of under-25s were undergoing similar procedures every year in the UK.
The average patient who underwent weight loss surgery at some point in the last three years had a body mass index (BMI) of 48.8, meaning they were almost twice they should be for their height.
Figures from the National Bariatric Surgery Registry (NBSR) revealed:
- Some 73.2% of men and 71.5% of women had what is known as functional impairment - meaning they could not climb three flights of stairs without resting.
- But after surgery more than half of those patients (56%) could manage three flights without resting, the report found.
- The mortality rate of patients after weight loss surgery was 0.07%, while the rate of post-operation complications was 2.9%.
- An increasing proportion of men are seeking surgery, the report found. In 2006, 16% of patients were male while by 2013 the figure had risen to almost 26%.
Hundreds of young people under the age of 25 had weight loss surgery in the last three years, according to a wide-ranging study.
Some 108 men and 462 women aged 24 or under had obesity operations between 2011 and 2013, according to the National Bariatric Surgery Registry (NBSR).
The register revealed 62 of those were under the age of 18.
There was some relief for overweight patients with diabetes - the NBSR showed 65% of obese patients who had undergone weight loss surgery with type two diabetes showed no sign of the condition two years after weight loss surgery.
On average, patients lost 58% of their excess weight a year after surgery, with the figure rising to 68.7% for gastric bypass patients alone.
The NBSR report, which looked at more than 18,200 operations from 2011 to 2013, said bariatric surgery could offer "significant financial savings to the healthcare economy".
Employees in England could be rewarded with cash or shopping vouchers for losing weight under NHS-backed plans to tackle the obesity crisis.
Simon Stevens, NHS England chief executive, said workplace health schemes had become a "blind spot" in the healthcare system:
The principal point is that employers in many countries have developed voluntary schemes for their employees whereby for example you actually get cash back based on participation in Weight Watchers or other type schemes.
The findings, published in the Lancet medical journal, suggest BMI was "positively associated" with 10 most common cancers, including uterus, cervix, thyroid, kidney, liver and colon.
Post-menopausal breast cancer and leukaemia were also a heightened risk, the scientists said.
A person is deemed to be overweight if they have a BMI score, calculated using their weight and height, of 25 to 30 and are obese if it is above 30.
Overweight or obese people are at greater risk of developing cancer, according to a major new study by the London School of Hygiene and Tropical Medicine.
Researchers from the school gathered data on 5.2 million people in the UK, of which nearly 170,000 developed cancer, and found that a person's Body Mass Index, a measure of body fat, was linked to 17 out of 22 cancers.
Men are more likely to stick to a weight loss regime, despite fewer of them trying to lose pounds in the first place, an analysis of international obesity studies has found.
Middle-aged men will choose to lose weight once a health risk is established, welcome the moral support of other men in weight-loss programmes and prefer "business-like" language and tactful humour.
Researchers from the universities of Aberdeen, Bournemouth and Stirling analysed evidence from around the world involving more than 15,000 men gathered from weight loss trials and studies.
Chief investigator Professor Alison Avenell, a clinician from the Health Services Research Unit at the University of Aberdeen, said:
"More men than women are overweight or obese in the UK, but men are less likely to see their weight as a problem and engage with weight-loss services, even though obesity increases the risk of many serious illnesses such as coronary heart disease, type 2 diabetes and osteoarthritis."
The boy has reportedly reached a weight of 15 stone, despite his Dad saying his favourite snack is steamed broccoli.Read the full story ›
More must be done to tackle the rising number of overweight "sumo babies", experts have said.
The number of larger-than-average newborns has been increasing since the 1960s because of the rising number of overweight and obese pregnant women, the National Obesity Forum said.
The average weight of a newborn is 7lb 4oz for a girl and 7lb 8oz for a boy, but figures obtained by The Sun found that almost a third of maternity wards have delivered babies weighing more than 12lb in the last year.
"It is a direct consequence of women going into pregnancy overweight and obese and thereby producing large babies. Unfortunately there is this old habit of 'eating for two'," Tam Fry of the National Obesity Forum said.
Sleeping with too much light in the room increases the risk of obesity in women, research has found.
Greater exposure to light at night raised both Body Mass Index (BMI) and waist size in more than 113,000 women, the Breakthrough Generations Study found.
The British study followed the women for 40 years in an attempt to identify root causes of breast cancer. Obesity is a known risk factor for the disease.
"Metabolism is affected by cyclical rhythms within the body that relate to sleeping, waking and light exposure.The results open up an interesting direction for research," Professor Anthony Swerdlow, from The Institute of Cancer Research in London, said.