Slimmer in half the time with The Ice Diet

It’s possible to drop weight by simply restricting the hours you eat during the day. Peta Bee looks at the latest science behind dining to a timetable.

BY this time of year, many people will have given up on a diet they started with gusto in January. Some were too hungry, others got bored counting calories and scrutinising food to eliminate ingredients.

It’s a familiar scenario that scientists say can be avoided by following a cutting-edge routine. You won’t feel tetchy, tired or hungry.

As a health writer, I have been scrutinising diets for two decades, only to find there is often little substance to their claims.

But evidence for the approach in my new book, The Ice Diet, (Penguin Books, €11.99) is convincing. And it works.

Findings now suggest that it is not just what we eat that matters, but when we eat it and, for speedy and lasting weight loss, our bodies respond best to short bouts of fasting.

However, on this diet, unlike with the 5:2, you will not be required to reduce your calories to a level of gnawing discomfort twice a week.

Instead, you adopt a 12:12 fasting approach: that means confining your food intake to a 12-hour period, and allowing your body a 12-hour break.

Researchers at the Salk Institute for Biological Studies, in California, recently became the latest to prove that the daily mini-fast is the most effective way to shed pounds. Permanently.

In a study published in the journal, Cell Metabolism, laboratory mice were fed one of the following diets: high-fat, high-fructose, high-fat and high-sucrose, or ordinary mouse food.

Some of the mice were allowed to eat whenever they wanted; others had their food limited to feeding periods of nine, 12 or 15 hours. All mice had the same number of calories, although some were allowed to ‘cheat’ by eating more at weekends.

At the end of the 38-week trial, the eat-around-the-clock mice were obese and had developed other risk factors for heart disease.

But the mice restricted to a nine- or 12-hour ‘eating window’ maintained a healthy weight, even if they fell off the wagon at weekends. When the other mice were switched to this daily regimen, they started to shed weight.

“Time-restricted eating didn’t just prevent, but also reversed, obesity,” says Professor Satchidananda Panda, who oversaw the studies. And the same approach works for humans.

The regimen’s appeal is simple. For starters, it is manageable. Timetabling chunks of the day when food is not consumed is incredibly easy to adopt.

No foods (other than the blatantly unhealthy) need be restricted and there’s no need for torturous calorie-counting, as long as it’s within prescribed limits.

Snacking is not allowed, but you won’t be tempted, because the two to three daily meals are nutrient-packed and filling. The beauty of it is you can schedule meals to suit whatever you have planned. It works to your own routine.

As you get used to your ‘eating window’, you can choose to squeeze it to 10 or 11 hours. I’m a bruncher, rather than a breakfast-eater, and like to eat with my partner in the evening, so my own eating window is between 11am and 9pm.

Stretching out the natural daily fasting period at night has other benefits. It revs up the body’s stores of ‘good’ brown fat, the kind that is activated by cooler temperatures and that enables us to burn calories like a furnace.

By wrapping up healthy eating into 10-12 hours, these mini daily fasts also protect against diabetes and a fatty liver, raised blood sugar and other metabolic ailments.

While no ingredient is banned on the Ice Diet, certain foods are included, because they accelerate fat-burning. Peppers (the hotter the better) have a powerful effect on metabolism, by firing up calorie-burning ‘good’ fat.

Likewise, a compound called ursolic acid, which is found in many fruits, vegetables and herbs — including prunes, cranberries, bilberries, basil, thyme and apples (the richest source) — can also sharpen your body’s fat-burning capacity. Processed foods are, unsurprisingly, avoided on the Ice Diet.

Last year, cardiologists at Boston University School of Medicine said sugar and bad fat triggered a “death spiral for good fat” by converting calorie-gobbling brown fat into the blobby white stuff that clings to our thighs.

Exercise is also crucial, but preferably not in the hermetically sealed, overheated boxes that are gyms. Get outside to expose your body to the cooler temperatures that speed up fat-burning.

There is no evidence that hot workouts offer benefits or that sweating increases your calorie-burn. On the contrary, it just feels like more effort — but for less return.

So, how do you get started? It is easier than you might think.

Consider your current eating patterns and when you are most hungry — really hungry, I mean, not just peckish because you are bored. Start with a 12:12 mini-fast (that’s eating within a 12-hour window).

If you have breakfast at 8am, your last meal should finish no later than 8pm. Ideally, stick to two meals a day (they are substantial), three if you are very active (or very hungry), but certainly no more than that.

And no snacking between meals. Once you feel comfortable with 12:12, extend your fasting period by an hour at a time, with the ultimate aim of cutting the window to 10 hours.

Dearbhla McCullough, a psychologist who has worked with many of Ireland’s top athletes, says that for an eating plan to be successful it must not be too restrictive.

“People give up easily when they are faced with unending hunger,” McCullough says.

“And that can set off the vicious cycle of adverse dieting behaviour.”

So, don’t worry if you get things wrong at first. There should be no shame in falling off the bandwagon as you adjust to your new routine. The Ice Diet is intended to be a plan for life, not a short-term hardship.

ICE DIET RULES

1. Ideally eat two substantial meals a day — three if you are very active (or very hungry!), but certainly no more than that, with no snacking between meals. Don’t worry, because portions can be quite generous.

2. Start with 12:12 (a 12 hour eating window) and see how you go for at least two weeks. Then try to extend your fasting period by no more than an hour a week with the ultimate aim of cutting your ‘eating window’ to around 10 hours.

3. Don’t be swayed by commonly held beliefs that one meal is more important than another in terms of nutrition. We were told breakfast was of prime importance for boosting the metabolism and reducing overall calorie intake.

That is now disputed by leading scientists and studies published in the American Journal of Clinical Nutrition. Choose when you want to eat your two to three meals and vary according to needs.

4. No snacks. Science has changed its mind about multiple small snacks being the favourable option for shedding weight. Indeed, a study at Purdue University found overweight people on diets felt more satisfied and less hungry when they ate three times a day compared to when they had six smaller meals.

5. Flavour food with spices and chilli when you can — not only do meals taste more appetising, but they can stimulate the appetite and the activity of ‘good’ brown fat in the body — the type that burns calories.