Fat was once said to be a feminist issue.

It is fast becoming an economic one. A quarter of Scots are now obese, we are told. That's more than one million people whose excess weight raises their potential to develop diabetes, heart disease and a slew of other expensive ailments. Together they could bankrupt the National Health Service.

An Edinburgh-based surgeon has one answer to a problem that is approaching like a tsunami. He advocates bariatric surgery. If you shrink a person's stomach and they can't eat enough to gain weight, kilos melt away. They return to a healthy size. Surgery, he argues, is a cost-effective investment.

The trouble is we have more than one million obese people but operate on only 200 a year. At that rate the NHS will be engulfed.

Money is needed to fund more surgery, says surgeon Andrew de Beaux. He asks whether money currently spent on giving the dying six or eight extra weeks of life at a cost of £20,000-£30,000 is the best use of resources.

He says: "It's trying to get a balance between very expensive treatments with very little benefit. But because they have emotive benefit, we spend money on them."

Is he right? Is it sentimental to spend limited cash resources on someone who will soon die anyway? Should we trim the budget for the final months and days of cancer patients and heart patients to offer the obese a lengthier, healthier future? Is your worth to mankind measured in the time you have left?

People will quote precedent. They'll say the Inuit habitually left their old and infirm to die on ice floes. But the claim is exaggerated. The practice was rare and usually restricted to famine conditions.

The simple fact is we don't love or value our family members less when they near death. If anything we value them more. If they still have a quality of life they can enjoy, don't they deserve to live as long as possible – even if their final days are financially costly?

Better provision of palliative care is espoused by the Scottish Government. It is welcome news for the rising tide of Scots who are over 75 years old and the one million plus who have a long-term health condition. A recent report estimates that three-quarters of the dying could benefit from palliative care.

People need and should have support when they confront the pain, breathlessness, fatigue, anxiety, depression and nausea that can accompany the end of life. We all want to look forward to "a good death". We want our loved ones to benefit from it. Why should they suffer to help the obese? But how would they – and how would we – measure a few extra weeks against a cost that runs to tens of thousands of pounds? Would it seem greedy?

It's a hard one. What does an air-sea rescue cost? What about the price of fetching a rambler off a mountainside? Car accidents involve police time and court time as well as incurring hospital costs.

Should we fight less hard to keep premature babies alive? Should we spend heavily to maintain the lives of people with long-term, life-threatening conditions? Once we start to choose who lives and who dies, where do we draw the line?

And yet Dr de Beaux has a point. Resources are limited and money must be seen to be well spent. The question then is, are the obese the most deserving of it?

I'm sure the surgeon would say his argument is economic. It's not one of personal merit. I doubt a terminally ill cancer patient who is denied life-prolonging drugs would agree.

Dr de Beaux says the obese cost the NHS £450 million a year. As they grow older and their ailments increase, the costs will rise. It's not as if they present a one-off challenge. With every passing year their numbers grow. Surgery can reverse the trend. It can make the obese slimmer and healthier – thereby saving the NHS a fortune.

Many will look at the argument with a cold eye. Most people can't help getting cancer, they will say. But most people can help getting fat. Why should the terminally ill suffer for the sake of the self-indulgent?

I'm not so hardline. I've been shocked on the scales too often myself. Weight seems to rocket upward and creep down. It's easy to reach a stage where you have so much to lose it hardly seems worth the effort. Fat is also a class issue: the higher the income, the lower the weight. Cheap food is fattening.

The Government could reverse that. It could and should tax fattening food and subsidise healthy fare. It should lead a national campaign to slim the population. Why should this be the first generation in history to die of fat?

With education and a little self-control we can shed the blubber and reverse the trend.

The latest research shows that fasting every other day – or restricting calories for two days a week – will reduce weight and extend life.

A BBC Horizon documentary screened last night showcased scientific evidence that drastically cutting calories for just two days a week can reduce weight, reduce cholesterol and lower glucose levels in the blood. If it is sustained it reduces the risk of developing cancer and diabetes.

There are the usual caveats that people should embark on the eating regime under the guidance of their doctor. Just think what could be achieved if we embraced fasting as a nation. It's achievable. Who would have thought that smoking would become a minority habit yet it has happened in a short timespan. When I was young, Friday was fish day for just about everyone. Lent was also commonly observed with people eating two snacks and only one main meal a day.

Given the scale of the problem, isn't it the Government's duty to get behind the idea of cutting calories to 500 or 600 for two days a week?

I'm not talking about a bread and water diet. Michael Mosley (who did the 5:2 diet for Horizon) ate scrambled eggs and a slice of ham for breakfast. He skipped lunch but ate fish and lots of vegetables for supper. He lost almost a stone in a month. It's bearable. It's economical for the family and for the NHS. If followed, it would improve the quality, the appearance and the lifespan of the nation.

In this simple way we can hold back the tsunami of obesity without a programme of mass surgery. We can prevent further generations from burying themselves in blubber. Peer pressure works. If a two-day fast becomes the norm, it's easier to join in than not.

It's worth a try. It's certainly fairer and more compassionate than gorging our way to ill-health – and in the process stealing precious days from the dying.