This scientist says you need to eat more fat if you want to burn more calories

If you're trying to squeeze into that new swimming costume next month, this scientist thinks he knows how to make it happen.

Nutrition expert Dr David Ludvig has further attested to the relatively modern argument that not all calories are built the same.

Back in the day, the simple equation of 'calories in, calories out' reigned. But Dr Ludvig has cast more light on the premise that our bodies treat certain foods differently.

For context, as Her reports, our bodies prefer being a little 'fat and comfortable'. It's an age-old response mechanism to keep us alive - when food is plentiful, we must stock up to keep us through the hard times. That's where the argument for things like the 5:2 diet comes from too.

Basically, while our diets today are kale and avocado, our brains are still locked into trying to 'regulate' our weight towards the plumper end of how you might hope to be while smashing it with the boys in Malia.

Ultimately, we're dependent on calories. In Dr Ludvig's latest study - for his new book Always Hungry? - he found evidence to say a diet in a more Atkins-style is more productive.

Dr Ludvig took 21 young adults with high BMIs. He brought their weight down by 10-15 per cent to begin with. Then, over a month-long period, he trialled three separate groups on three varying diets.

The first was low-fat, 20 per cent, 60 per cent carbs, the second was 60 per cent fat, and the third was 40 per cent fat, 40 per cent carbs.

Every person was given the same amount of calories.

And the Atkins-type plan prevailed resolutely. The difference was 325 calories a day extra burned on the high fat, low carb plan.

Dr Ludvig said:

Energy expenditure (metabolism/calorie burning) plummeted on the low fat diet. On the low carb (high fat) diet, energy expenditure - metabolic rate - didn't drop at all. Despite the weight loss, a low carb diet had completely abolished the negative effects of weight loss. Meta-training diet was in the middle.

We're not saying go out and try the Atkins Diet. We already knew that, at face value, cutting carbs works. But that doesn't mean it's at all healthy. It can actually pretty disastrous in the long-term.

What's more digestible here is that it appears to give more evidence to say that not all calories are the same: 2,000 calories from sugary food aren't the same as high protein, omega 3-rich produce, such as fish.

Dr Ludvig continued:

If you simply focus on calorie restriction with the wrong food, you're going to be setting up a battle with mind and metabolism that you're likely doomed to lose.

So go out and have some haddock poached in olive oil and lemon. It'll keep your metabolism fast and burning.

More: This chef tricked food experts into eating McDonald's

More: Seven 'healthy foods' that are really junk foods in disguise

HT Her.ie