THE vast majority of obese patients undergoing weight-loss surgery do not know how to cook a simple meal, one of Scotland's leading bariatric surgeons has said.

Dr Majid Ali, who has headed up one of the country's busiest bariatric units at University Hospital Ayr since 2007, said few of his patients had basic culinary skills or sat down to eat a proper family meal even if they owned a dining table.

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He said the nation's ballooning waistlines could be traced back to the rise of household microwaves in the 1980s and an increasing reliance on ready meals over home-cooked food.

Dr Ali, who stars in a new BBC Scotland documentary 'Shedding the Fat' which goes behind the scenes at the hospital, said the Scottish Government were right to try to curtail the obesity crisis with restrictions on junk food deals.

HeraldScotland: Dr Majid Ali preparing a patient for surgery

However, he also stressed that spending more to provide procedures such as gastric bands would save the NHS money in the long-term.

Speaking to the Herald ahead of the programme's debut, Dr Ali said: "If you look at the population data for the UK, it shows that obesity starts rising in 1984 - so something went wrong in 1984. Then we start seeing a just under 1% year-on-year increase in obesity rates.

"In fact this was also the period where the ownership of microwaves increased and people started seeing ready-meals appearing on the supermarket shelves and it became cheaper and more convenient just to stick something in the microwave and within a few minutes you have a meal - although you don't necessarily know what's in that meal.

"One of the things that always shocks me is that families in Scotland, and the UK, don't sit down to a meal together at a table. More than 80% of my patients, even if they have a dining table, they don't sit at it and dedicate time for a meal.

"More than 80% of my patients have no interest in food - they don't know how to cook a simple meal - whereas the other cultures which have low obesity, like the Japanese or Mediterranean countries, food is part of their culture.

"They talk all the time about food, but they don't have the scale of obesity Scotland suffers from."

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Previous studies have shown that adult obesity rates tripled in Britain between 1980 and 2002, with prevalence increasing faster in Scotland than England.

By 2017, 29% of people aged 16 and over in Scotland were obese and Food Standards Scotland has warned that this is on track to soar to 40% of the adult population by 2030 unless the nation's calorie intake is drastically reduced.

Last week the watchdog launched a consultation on proposals for maximum calorie limits on out-of-home food, such as takeaways, restaurant portions and cinema popcorn. It also suggested banning some very high calorie items from menus and making calorie labelling on menus mandatory rather than voluntary.

It follows on from the Scottish Government's own obesity strategy, unveiled in July, which outlined plans to restrict retailers from selling foods high in fat, sugar or salt in multi-buy deals and outlawing the promotion of junk food and confectionary at checkouts.

It is also supportive of calorie caps on fast food and a pre-watershed ban on television advertising of unhealthy food and alcohol.

Dr Ali, the clinical director of surgery & endoscopy at University Hospital Ayr, said it was a "step in the right direction". He said: "It is an interesting concept to have control over marketing of food in the same we we have controls over smoking, for example, or alcohol. We need to have that control.

"But it is a complex disease, and for a complex disease there cannot be one solution."

Dr Ali operates only on patients with 'severe and complicated' obesity, which means they have either Type 2 diabetes or sleep apnoea as well as a BMI of 35 or more.

Before surgery, they are required to lose 5% of their bodyweight and also training with dieticians and counsellors to change their relationship with food.

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The majority also have psychological difficulties which means overeating is like "building a shield" around themselves, said Dr Ali.

"The stereotype that we have of patients that they are regarded as lazy or lacking in self-discipline, but it can lead to feelings of moral failure and guilt," he said.

"I have heard many stories from my patients, and internationally when I attend conferences, they will 'build a shield' around them and continue to eat. They just need help to get them out of the cycle.

"Around 60% of bariatric patients have psychological disorders. Depression and anxiety is at the top, and what research has shown us is that around a third of obese patients were victims of physical or sexual abuse and that's why they build that 'shield' around them."

There are no routinely published figures on the number of bariatric surgeries carried out in NHS Scotland, but previous data from 2014 indicated that it was averaging around 200-300 per year, much lower than neighbouring European countries including Belgium and Sweden which respectively perform around 12,000 and 7,000 per year.

Weight-loss surgeries cost around £6000-7000 per patient, but there have been calls to increase them in the UK to reduce the costs from obesity-linked illnesses and complications.

Dr Ali said: "The funding is very limited for bariatric surgery. I can understand that because I am the clinical director at the hospital so I understand the budget pressures, but I am also a clinician so I see it from both sides. People can lose weight but the problem is sustaining that weight loss.

"We know surgery is the only sustainable way of treating this, or at least the most successful.

"So we have a disease where we know the cure, but it's very expensive to treat. There are other diseases which also require priority, like cancer, heart disease, diabetes - these are common - but 29% of the Scottish population are obese. If we opened the door to 29% of the population for surgery, the public funds could not cope.

"But on the other hand, if we concentrate on patients who have potentially curable diseases that are expensive to treat, like Type 2 diabetes, we know we can operate and cure their Type 2 diabetes and save a lot of money.

"Diabetes comes with a lot of complications: leg ulcers, eye problems, heart disease, so if we can prevent or reverse the Type 2 diabetes then we can save money. You need to have some way of interrupting that cycle."