50st Zac Smith of Rhoose pays for operation in India

A man weighing 50st (317kg) has told how he went to India and paid for a weight loss operation after failing to qualify for the procedure on the NHS.

Zac Smith, 37, of Rhoose, Vale of Glamorgan, borrowed family savings for treatment to reduce his stomach, reports BBC Wales' Week In Week Out.

The Welsh Health Specialist Services Committee funds the procedure in Wales, but only if patients meet all criteria.

The Welsh Assembly Government and NHS will not comment on individual cases.

"I'm angry they turned me down," he told the programme, Wales' Biggest Slimmer, which highlights the plight of people like Mr Smith who view surgery as the only way to lose weight.

Despite a body mass index of 72.6, Mr Smith was told he did not qualify for an operation on the NHS because he also needed to also have a severe illness associated with obesity, such as diabetes or hypertension.

But the Welsh Health Specialised Services Committee (WHSSC) - responsible for planning specialised services on behalf of local health boards in Wales - funds gastric banding or gastric by-pass "where a patient meets specific clinical criteria".

Weight loss or bariatric surgery, which reduces the amount a patient can eat by altering the digestive system, is limited in Wales.

Only around 50 of the operations are approved each year on the NHS.

According to estimates calculated for the programme by University of Glamorgan health economist Siobhan McClelland, there are about 430 people in Wales who are suitable for weight loss surgery.

Zac Smith undergoes his weight-loss operation in India to reduce his stomach by 80% in capacity

She estimated that operating on those people would cost the NHS an extra £2.5m a year, but would save Wales £9m in reduced benefit payments.

The assembly government said it was doubling the amount of funding allocated to bariatric surgery this year, but said any morbid obesity service must demonstrate cost effectiveness and represent value for money.

But Mr Smith told Week In Week Out current NHS advice did not help people who are "super or morbidly obese".

"You can't give someone who's struggled all their life with weight a diet sheet and information on exercise and pat them out the door and say good luck. It just isn't going to happen," he said.

Despite fearing he may die on the operating table, Mr Smith undertook the gastric sleeve surgery which reduced the size of his stomach by 80%.

Week In Week Out has been following his progress for the past three months, as he embarks on an attempt to lose more than 30 stone after the operation in November.

"This operation's just a tool, and it's up to me now to use it properly," he said.

Week In Week Out is on Wednesday, 2 March on BBC One Wales at 2245 GMT.