Dieting made easy Your new plan of attack
Opt for a one-rule eating plan and you increase your chances of losing weight and keeping it off
On five days you eat normally and on two days each week you eat far less (around 2100 kilojoules for women and 2500 kilojoules for men). Originally called the ‘2-day diet’, it was developed at the Genesis Breast Cancer Prevention Centre, in the UK, to help reduce breast cancer risk. Since then the 5:2 fast diet and Intermittent Fasting (IF), has been championed by health guru, Dr Michael Mosley. “Despite the name, IF does not involve complete abstinence from food,” says Melanie McGrice, dietitian and spokesperson for the Dietitians Association of Australia. “On the ‘fasting’ days you eat plenty of low-starch vegetables and low-carbs food, along with a little lean protein.”
While crash diets may slow your metabolism, part-time fasting keeps your metabolism guessing. “The fasting days are kept to a short window of time each week or month, so you get all the benefits without any drawbacks of severe and constant kilojoule restriction,” says Associate Professor Amanda Salis, senior research fellow from the University of Sydney’s Boden Institute of Obesity, Nutrition, Exercise and Eating Disorders. How does IF compare to conventional weight-loss diets? “Both strategies appear to be equal,” Salis says. “But there are studies showing that many people find the IF approach easier to stick to because food restrictions are only applied several days a week.”
Tailoring this for you
After medical advice, you may choose to:
• Go on a low-kilojoule eating plan across a week on consecutive days or split up. On those days, reduce intake of carbs and eat non-starchy vegetables and good quality protein. “Before trying this it is important to consult a medical professional or dietitian with diabetes experience, about how many kilojoules you should consume on ‘fasting days’,” says diabetes educator and dietitian, Dr Kate Marsh.
Try a range of other approaches if you are type 2. These include:
• Restricting all eating to a window of 10 hours
(eg 8am to 6pm) each day.
• Eating half as much as usual every second day.
• Fasting for 24 hours two times a week (either consecutively or alternately), consuming drinks like broth, but no solid food.
The upside
Research shows that intermittent fasting:
• Leads people to adopt healthier eating on non-fasting days.
• Stabilises blood glucose levels (BGLs) and improves insulin sensitivity,
encouraging stable BGLs, weight loss and healthy weight maintenance.
• Triggers the growth of new insulin-producing pancreatic cells in mice, shows research by the University of Southern California. As a result, late stage type 1 and type 2 diabetes in mice reversed. In the future, this may mean part-time fasting could help people with diabetes gain more control over their insulin production and blood glucose. Research is now underway to see if IF can also help put type 2 diabetes into remission.
• Reduces cholesterol: on the ‘fasting’ days the body pulls cholesterol from fat cells to use for energy, shows research by Intermountain Medical Center.
Potential pitfalls
When engaged in part-time fasting bear in mind that:
• “Intermittent fasting isn’t safe for everyone,” says Dr Marsh. “It may require adjustment to medications, including many diabetes medications (particularly insulin and sulphonylureas), blood pressure medications and warfarin, so speak to your doctor before you consider this sort of eating plan.” It could also increase risk of hypos in some people with type 1.
• You may have less energy to face the gym or go for a run on days you eat fewer kilojoules.
• Some people find cutting back on kilojoules causes an enormous spike in their hunger and preoccupation with food, which makes the fasting day feel very long.
• Your alertness may drop; if so, schedule fasting days when you are not too busy. You give meat a miss on two or more days a week. Still love a juicy steak or chicken dish? No problem. Enjoy them on your meat-eating days.
Tailoring this for you
Some people do two consecutive vegie days while others eat vegetarian every second day. Or you could try the approach of Mark Bittman, food writer for The New York Times and author of Vegan Before 6 (Sphere, $29.95). Several years ago, overweight and heading for diabetes and a heart attack, he turned his health around with his flexitarian approach. He now eats fruit, veg, whole grains and no processed foods during the day and only eats meat after 6pm.
The upside
“Flexitarians often exceed the recommended daily intake of five servings of vegetables on their vegie days,” says McGrice. “They consume a wider range of vitamins and minerals and eat less saturated fat and more fibre, which helps protect against diseases like cancer and conditions like diabetes. Their high intake of whole grains, nuts and
good oils are also good for healthy cholesterol.” This is a win-win for your waist. “Your weight benefits from the lower kilojoule intake on the days you eat a plant-based diet and over the course of the week, that may balance your overall kilojoule intake enough to help prevent weight gain over a year.”
In one study comparing diets at the University of South California, people following vegetarian diets lost more weight. At six months, they were still sticking to the diet about 40 per cent of the time and maintaining weight loss or losing more, when the meat eaters were not. Without intending to, they had gone flexitarian!
There are many health benefits:
• For every 200-gram increase in your daily fruit and vegetable intake your risk of disease drops by six per cent, shows research from the Andalusian School of Public Health. • Eating leafy greens can significantly lower the risk of developing type 2 diabetes, according to a University of Leicester study.
• While two days eating a diet high in meat and dairy foods increases bad belly bacteria, two days of a vegetarian diet boosts the good bacteria again, shows Harvard University research.
Potential pitfalls
• Consuming too many high-fat foods. If you drown healthy meals in creamy sauces or cheese you’ll only add kilojoules to your veg.
• Eating too much fruit or fruit juice. “A fresh fruit juice contains far more pieces of fruit in a drink than you would ever sit down and eat,” says McGrice. “But because the fibre has been removed the juice leaves you less satisfied, even though it has more kilojoules than just snacking on a piece of fruit. As a result, it can quickly raise BGLs.” • Overdoing carbs or bread. “If you’re often eating toast with cheese and butter or tomato sauce on a bit of pasta, that’s not a healthy vegetarian meal,” says McGrice. “So make sure vegetables are the main feature, not an afterthought.”
While crash diets may slow your metabolism, part-time
fasting keeps your metabolism
guessing