Is intermittent fasting good for you?

Health and diet trends come and go and one of the biggest of recent years has been intermittent fasting.

From top athletes to medical doctors, it seems like everyone has backed it.

Weight-loss and a reduced risk of developing some chronic health conditions are all possible benefits.

But popularity doesn’t always mean success. Learn more about intermittent fasting to find out if it might work for you.

Intermittent fasting switches between 2 distinct phases: a period of no food or severely restricted calories, and a period of unrestricted eating. The length of each period depends on which style of fasting you choose.

2 of the most popular types are:

• the 5:2 (5 days of unrestricted eating and 2 of fasting each week)
• the 16:8 (limiting all your meals to one 8-hour period during the day and fasting the remaining 16 hours. For example, you might choose to eat between the hours of 10am and 6pm each day only).

Advocates of fasting say that going without food gives the body time to fully exhaust its supply of glycogen (glucose stored in your liver) and start burning fat.

“Intermittent fasting can assist in weight management, improve blood sugar levels and it provides a chance to eat more mindfully,” says Bupa Dietitian Corinne Tighe.

One review found intermittent fasting resulted in a typical loss of 3 to 5kg over 10 weeks, and there’s research suggesting intermittent fasting may improve memory and mood while also reducing the risk of Alzheimer’s and Parkinson’s disease.¹ However, there is also a study showing intermittent fasting is no more beneficial for weight loss than conventional dieting.²

One of the biggest challenges of this type of eating plan is what you eat on non-fasting days or periods of time when you can eat normally.

“People may find they can’t stick to the plan long term,” says Tighe. “Some people fill up on ‘sometimes foods’ during the regular eating days and this isn’t so beneficial for health.”

Simply put, because the periods of fasting can feel quite restrictive, there is a risk that during your windows of time when you can eat, or on non-fasting days, there may be a tendency to overeat or become overly restrictive in the way you eat.

Tighe warns intermittent fasting is not recommended for people who are pregnant or breastfeeding, the elderly, people who have diabetes or people who are on medications.

Even if you don’t fall into those groups, this method of restricting calorie intake may not suit you.

“Think about your current lifestyle and whether intermittent fasting could work for you,” advises Tighe. “With both the 5:2 and 16:8 plans, you need to be organised and think ahead for the week. Meal planning and doing a weekly food shop can help with this.”

It might also be helpful to think of what your goals are with intermittent fasting. Talking to a professional can help you work out the best way to achieve the goal.

“The best thing to do before starting an intermittent fasting plan is to see an Accredited Practising Dietitian or health professional who can help you work out a plan that will meet your nutritional needs.”