The Zone Diet Under the Spotlight

Reviewed by Dietitian, Juliette Kellow BSc RD

Sandra Bullock, Demi Moore, Sarah Jessica Parker and Jennifer Aniston might all be big in Hollywood, but their celebrity status isn’t the only thing they have in common. All these stars claim to have followed the Zone Diet to help them get – and keep – their famous figures. But just what does ‘Being in the Zone’ involve and more importantly, is it a healthy way to shift those pounds? Dietitian Juliette Kellow investigates…

‘Enter the Zone’ and you’ll lose weight permanently, achieve peak physical performance, enhance mental productivity and delay the signs of ageing. At least that’s what Barry Sears, creator of The Zone Diet, tells us!

In the mid 1990’s, the Zone was all the rage with many celebs, including Jennifer Aniston and hubby Brad Pitt, all claiming to be fans of the plan. Before long, millions of people were following the Zone and the diet had become a household name. Now, even though newer diet plans such as the Atkins and South Beach Diets gain more column inches and their books currently head the New York Times Bestseller list, the Zone Diet continues to remain a popular choice for some.

What’s the theory?

The Zone Diet works on the theory that excess insulin, a hormone that helps control our blood sugar levels, makes us fat and keeps us fat. By closely regulating our blood sugar levels and therefore keeping our levels of insulin in a tight ‘zone’, the body burns fat more efficiently so that we lose weight.

To control blood sugar levels and consequently insulin levels, you need to get the perfect balance of carbohydrates, proteins and fats in every meal. Achieving this perfect balance effectively means following a low-carbohydrate, high-protein diet that includes moderate amounts of fat. And if that sounds familiar, you’d be right! In fact, the Zone Diet is not too dissimilar to many of the other low-carb, high-protein diets that are currently in vogue, either in terms of the theory or the foods you can and can’t eat.

What does the Zone Diet involve?

If the theory sounds simple, the reality is far more complicated. First off, you’ll need plenty of patience, a head for science and the desire to learn more about ‘zoning’, either by looking at the Zone website or indulging in some bedtime reading, courtesy of creator Barry Sears.

The idea is that to reach ‘The Zone’, every meal and snack should provide 40 percent of calories from carbohydrate, 30 per cent from protein and 30 per cent from fat. This is what some Zone fans call the 40:30:30 ratio.

To help with this, ‘Zone Food Blocks’ have been developed, where each ‘block’ contains a standardised amount of carbohydrate, protein or fat. To lose weight, a certain number of blocks are allocated for each meal and snack.

The number of Zone Food Blocks you should have each day is calculated according to your weight, height and waist and hip circumferences. Generally, the bigger you are, the more blocks you are allowed. For example, a woman who weighs 10st, is 5ft 2in, has a 28in waist and 37in hips should have 12 blocks a day (four for breakfast, three each for lunch and dinner, one for an afternoon snack and one for an evening snack). Meanwhile, a larger woman who weighs 12st, is 5ft 10in, has a 30in waist and 40in hips needs 14 blocks (four for each main meal and one each as an afternoon snack and an evening snack).

With help from Weight Loss Resources or the Zone’s website, Zone Perfect, calculating the daily number of blocks you should have – and how they should be divided throughout the day – is the easy bit. Creating meals and snacks that have the correct number of Zone Foods Blocks is the hard bit! No surprises then that you really need a Zone Diet book to help you put meals together. And if that’s still too much like hard work, there are many pre-packaged Zone Diet meals and snacks for delivery that you can order over the Internet – at a fairly hefty price!

This sounds like hard work! Is there an easier way to follow it?

Although the creator of the diet is quite adamant that for best effects you should really stick to counting Food Blocks, it’s still possible to follow the basic principles of the diet without going through this complicated process.

In simple terms, the Zone diet involves cutting out most carbohydrates such as breakfast cereals, rice, potatoes, pasta, noodles, bread, bagels, croissants, muffins, crisps, pastries, pies, chocolate, sweets, sugar and preserves, as these have the greatest effect on blood sugar levels and therefore insulin levels. Most fruit and vegetables, however, are allowed. Low-fat protein-rich foods such as skinless chicken, turkey and fish should be eaten with every meal. Meanwhile, eating fewer foods that contain saturates and choosing foods that are rich in monounsaturates, such as olive oil, avocado and nuts, is recommended.

To make the Zone Diet even easier to follow, the creator recommends dividing your plate into three equal sized sections and then filling one section with low-fat protein such as chicken – making sure it’s no larger or thicker than the palm of your hand – and the remaining two sections with vegetables and fruit. Adding a little olive oil, avocado or a few nuts will help to boost intakes of monounsaturates!

So how much weight can I expect to lose?

Advocates of the Zone Diet claim you can lose at least 5lb in the first two weeks, followed by 1-1.5lb every week after this.

What do the experts say?

Achieving a 40:30:30 ratio is certainly a departure from current healthy eating guidelines, which recommend 50 percent of our calories should come from carbohydrate, 15 percent from protein and 35 percent from fat. While most nutrition experts agree with the advice to eat less fat, especially saturates, and to fill up on fruit and veg, most remain sceptical about the theory that weight loss is due to regulating insulin levels. They still believe that eating fewer carbohydrate-rich foods results in a calorie deficit – in other words, any weight loss that occurs is due to taking in fewer calories than the body uses up. In fact, if followed properly, the diet provides around 1,000 to 1,300 calories a day, thanks mainly to cutting out most high-calorie sugary and starchy foods – and replacing them with low-calorie vegetables and fruit. And if you’re still not convinced, maybe this example will help: swap a large Danish pastry, containing around 650 calories, for a 50-calorie apple and you’ll save a staggering 600 calories. Do this every day for a week and you’d expect to lose more than 1lb in a week!

Are there any pros?

The Zone Diet generally has fewer dietary restrictions than many other low-carb plans and recommends eating more fruit and vegetables. It also encourages you to cut out a lot of the ‘junk’ or low-nutrient carbs in your diet such as crisps, cakes, biscuits and chocolate. Eating fewer fatty foods – and swapping foods that are high in saturates for those containing monounsaturates – is sensible, heart-healthy advice, too.

And the cons?

Unfortunately, the Zone Diet is very complicated and time-consuming if you’re going to follow it properly. You’ll need to invest in a Zone diet book and a decent set of measuring scales and spoons if you don’t already have them. It also recommends eliminating some very nutritious foods, which are not only a good source of carbohydrate but are also packed with fibre and important vitamins and minerals. For example, wholegrain cereals are packed with fibre, B vitamins and iron, while cheese is an excellent source of calcium and zinc. It can also be really expensive if you decide to purchase pre-packaged Zone products! As for eating out – if you’re counting Food Blocks, you might as well forget it.

Juliette’s verdict

The Zone diet is undoubtedly hard work and in my opinion turns mealtimes into a chore rather than a pleasure. While the creator of the diet suggests that Zone Food Blocks help to make the diet easier to follow, I have to disagree – trying to get your head around blocks of carbohydrate, protein and fat after a busy day in the office or with the children is just not feasible! And I certainly don’t believe in weighing and measuring every single ingredient before preparing it. Ultimately, the diet is low in calories and this is why it results in weight loss. However, there are far easier and more pleasurable ways to lower your calorie intake – healthy eating with smaller portion sizes, for example!

Try It Free

Use the Weight Loss Resources tools to find the diet right for you. You can keep online food and exercise diaries, set a weight loss goal and see how many calories you need each day to get there. Try it free for 24 hours.

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More Information

You can use Weight Loss Resources to follow the Zone diet by setting your target nutrition profile (in the Food Diary) to the 40:30:30 ratio. 40% of calories from carbohydrate, 30% from protein and 30% from fat. Start a free trial to try it out.

Alternatively log on to the Zone Perfect web site for more information.

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