A test on BBC'sTrust Me, I'm a Doctor has found that reheating cold pasta makes it healthier than the original meal.

The show's doctors conducted an experiment and concluded that cooking, cooling and reheating a bowl of pasta turned it into "resistant starch" and reduced the rise in volunteers' blood glucose by 50 per cent.

Pasta and potatoes titillate our tastebuds, but they have become outcasts in a low-carb, low-GI worshipping world.

It's not just the fact they pair so perfectly with kilojoule-laden toppings. The problem with potatoes and white pasta, for many health and weight-conscious people  - not to mention those with diabetes - is that the starch (a form of carbohydrate) they contain quickly converts into simple sugars.

This spikes our blood sugar. To bring it back into balance, our bodies respond by releasing the hormone insulin.

The fast rise and fall can make us hungry again soon after eating and the sugars, if not burnt off, are likely to be stored as fat.

But, in perhaps the most unlikely nutrition news of the year, researchers reckon they've found a way around the pasta-potato predicament.

A nutrition scientist from the University of Surrey has said that if you cook and cool pasta, it changes the structure of the food and your body digests it more like a fibre, which results in less of a blood sugar spike to feed the good bacteria that reside in your gut and absorb fewer calories.

But half the pleasure of such foods is are that they are eaten piping hot. If pasta, for instance, was reheated, would it revert to its original structure?

British journalist, doctor and author of the best-selling 5:2 diet,  MIchael Mosley along with co-presenter on Trust Me, I'm a Doctor, Chris van Tulleken from University College, London asked around.

The doctors they approached believed it would, but no one had tested the theory.

So, they decided to find out. They recruited volunteers who, over three days,  ate either hot, cold or reheated pasta. Each pasta had the same tomato and garlic sauce.

On each day the doctors took blood samples every 15 minutes for two hours, to see what happened to volunteers' blood glucose levels as they digested the pasta.

"Just as expected, eating cold pasta led to a smaller spike in blood glucose and insulin than eating freshly boiled pasta had," Mosley said.

"But then we found something that we really didn't expect - cooking, cooling and then reheating the pasta had an even more dramatic effect. Or, to be precise, an even smaller effect on blood glucose.

"In fact, it reduced the rise in blood glucose by 50 per cent."

Dr Chris van Tulleken said the discovery was a way to "simply and easily" improve our health.

"We can convert a carb-loaded meal into a more healthy fibre-loaded one instead without changing a single ingredient, just the temperature," he said. "In other words our leftovers could be healthier for us than the original meal."

Sports nutritionist Susie Burrell says it's not news that cooled pasta, potatoes and even unripened bananas have higher levels of resistant starch

"Yes there are some benefits but in the overall scheme of the diet as long as pasta serving sizes are small it won't make that big a difference," she says.

"For the average busy person it may not be practical either and  you can get an equal benefit from eating less pasta and more vegies in any one meal."

Dietitian Melanie McGrice says the discovery isn't too good to be true, necessarily.

"It's not really going to mean we're going to lose more weight," she says.

"There's a lot more to losing weight than eating resistant starch.

"But, most of my clients are time-poor and pasta freezes really well. Cooking and reheating can provide double the benefits - it saves you time and increases the amount of resistant starch you eat, so it's a win, really."