Apart from the immediate risks of complications associated with a major surgery, you put yourself at risk of a clutch of problems: osteoporosis, anaemia and other nutritional deficiencies, bowel obstruction, gallstones, hernia, ulcers, stomach perforation, and/or gastric dumping syndrome, characterised by frequent diarrhoea and vomiting.
And then there's still more - depression, alcoholism and suicide.
All bariatric "weight-loss" surgeries aim to make you eat less. They involve either stapling or banding your stomach to make it smaller, or creating a gastric bypass, where the stomach is made smaller and the gut shorter.
While these surgeries treat and even cure severe obesity-related conditions such as gastroesophageal reflux disease, heart disease, high blood pressure, sleep disorders and Type-2 diabetes, they are increasingly being misused as just another way of losing weight.
But bariatric surgery is more than a dental extraction that you fret over but forget about after it's over.
The US Department of Health and Human Services data for 2011 shows that overall, 7.3% people who underwent bariatric surgery had complications, though mostly minor, while they were in hospital for the surgery. But 2.5% had serious complications, which were highest for people undergoing gastric bypass (3.6%), followed by sleeve gastrectomy (2.2%), and laparoscopic adjustable band procedures (0.9%).
Corresponding data for India is not available, but the US data showed that serious complications were fewer when the surgery was done by high-volume hospitals and surgeons. In other words, if you must go for the surgery, choose an experienced surgeon to stack the odds in your favour.
An unexpected side effect is depression, which happens even to people who lose all the weight they want to. And it's not just to do with unrealistic expectations from the surgery or being left holding amounts of unsightly loose skin after weight loss. (Almost everyone who undergoes bariatric surgery needs a tummy tuck -abdominoplasty, or removal of excess skin and fat from the stomach to tighten and firm up the abdomen - which is another major surgery that some surgeons don't warn them about).
The depression is acute enough to push up the suicide rate five-fold after bariatric surgery compared to the general population in the US, reported the journal Archives of Surgery.
The findings held even among a comparison of the obese who had undergone surgery and those who hadn't. A review of nearly 10,000 bariatric surgery patients in New England Journal of Medicine showed that suicide risk was twice as high for surgery patients than for the obese people who didn't. Another study found that one-third of patients with no depression before surgery developed depression after the operation.
Another potential risk is alcoholism. Within two years of surgery, 11% of gastric bypass patients developed drinking problems, reported The Journal of the American Medical Association, which may be a result of people becoming more sensitive to absorbing alcohol after surgery, or simply becoming more social.
Reality does not always live up to the preoperative fantasy of improved quality of life and many have to struggle to control emotional eating. Mild depression after surgery is not uncommon, but severe depression is much less common, so any talk of death should be a red-flag.
Changing food habits before surgery make adaption to a new diet easier, exercising to accelerate weight loss, and bonding with friends and family for emotional support can help reduce post-operative stress and, with it, depression.