Fry-ups, burger and chips, fizzy drinks and ice cream for pudding. You would expect to see these delights on the menu at a McDonald's or Burger King. But, sadly, this is the sort of food that is also likely to be served at your local hospital.

I work as a cardiologist at one of Britain's leading cardiac centres. I have been a qualified doctor for almost a decade, working in many hospitals throughout the country, and I am extremely proud to occupy a privileged position treating cardiac patients. Coronary artery disease is the biggest killer in the western world and a significant part of my job involves performing a lifesaving procedure, angioplasty, to restore the blood supply to the heart muscle. Coronary atheroma (fatty deposit within the artery wall) takes many years to develop and is the culmination of risk factors, of which lifestyle – and diet in particular – is a major contributor.

As a clinician, it is very difficult to reconcile the paradox of a treatment centre administering life-prolonging medications and at the same time serving unhealthy and often unpalatable food to patients and staff. The majority of hospitals spend an average of less than a pound on each meal per patient. Children are given options such as chicken nuggets, sausage rolls, fish fingers, pizzas and pasties. Often, the only vegetable choices are peas or sweetcorn.

Colleagues constantly tell shocking tales of the food served up but feel powerless to do anything. A cardiologist at another hospital was horrified to see the patient he had treated for a heart attack the night before tucking into a fry-up in his hospital bed the next morning. Even the patient said to the nurse: "How do you expect people to change their eating habits when they go home if the very place they come to for healing is serving them the same crap that got them here in the first place?"

Addenbrookes Cambridge, a well-known cardiac centre, has a Burger King on site where it is very common to see patients with heart conditions devouring double whoppers with cheese and french fries. I find this sickening.

How did we allow this to happen? Throughout my medical training, we were taught the ethos: "Prevention is better than cure." Obesity and its related conditions such as diabetes can only be seriously tackled with lifestyle changes and hospitals need to set the example. As health professionals, we cannot stay silent and allow this public health disaster in the making to continue.

It is appalling that there is no strict regulation on what is served. What kind of message are we sending to our patients by routinely offering them such unhealthy food? Thanks to Jamie Oliver, school meals in England must meet minimum nutritional standards. So why does this not apply to hospital food?

In my frustration, I wrote to Oliver last year to seek his help in cleaning up this mess. I joined a group of health professionals and campaigners who met him to discuss how we need to make food healthier in so many areas of our lives. His view on hospital food is simple. He said: "I can never understand why places that are supposed to care for people and make them well generally fail to provide the nutrients that will help the healing process. It seems completely crazy to me." How right he is.

In England, more than 60% of adults and more than 30% of children are either overweight or obese. We are now officially the fattest nation in Europe. Without effective action, this could increase to nine out of 10 adults and two-thirds of children by 2050. The link between obesity and preventable illnesses such as diabetes, heart disease and cancer is unquestionable. Diet-related ill health costs us £6bn a year and 70,000 deaths could be avoided if diets met nutritional guidelines. These rising costs threaten to cripple and bankrupt the NHS as we know it.

Education is extremely important but is clearly not enough. Despite numerous healthcare campaigns, the evidence suggests that we are becoming less effective at preventing obesity. There is a very compelling argument that processed foods are to blame for our current crisis and we need a return to natural cuisine. Jamie has given a bit of a kick to the school meals service to make sure it provides good, healthy meals and I would like him to do the same for hospital patients. He certainly appeared keen to explore his possible involvement in improving hospital food standards. This would raise public awareness that would bring great benefits to millions of patients and this would further inspire consumers to choose healthier food when out of hospital care.

But one person cannot tackle this alone. Robust regulation and legislation from the government is long overdue. Inviting McDonald's and Pepsi to have input in the public health agenda is akin to the lunatics taking over the asylum. Not only is this a smokescreen to fit in with the current administration's ideology that responsibility lies purely with individuals, (one which got us into this mess in the first place), but it also sends a message that we care more about the profitability of food manufacturers than we do about the health of our citizens.

When it comes to health, the government should not be afraid of being accused of the "nanny state" approach. In my opinion, the greatest legacy of the last Labour government was the introduction of the smoking ban in public places. This is already having an impact in saving thousands of lives. Even the majority of smokers would concede that it was proper and necessary.

Patients deserve to be served fresh food that is cooked on site. There are a few beacons of good practice; the Royal Brompton NHS trust (the trust where I work) in London is a prime example, where a team led by chief caterer Mike Duckett has worked to utilise their budgets to provide meals using fresh, seasonal produce.

He believes, as I do, that there should be one consistent menu across the NHS which would be both nutritious and affordable. Outsourcing hospital food means that often frozen food is brought in and reheated. This is not only unhealthy but also unappetising for patients, many of whom need building up. Hospitals should set an example of what healthy eating means.

We have the potential to save thousands of lives and improve the future of our children. I would like hospital trusts to double their spending on hospital dinners; to lay down fixed and enforceable nutritional standards; to increase investment and training in catering staff; and to improve food education so that we can be sure it is safe, enjoyable to eat, supportive of health and good for the environment. Vending machines selling chocolate, crisps and fizzy drinks should be banned from hospital grounds.

We have a crisis and crises require major interventions, not the selling of our lives to the interests of big business.