10 things to know about 16:8 intermittent fasting

The 16:8 is a popular take on time-restricted eating – but is it a magic formula for weight management? Spoiler alert: You still need to make good food choices.

With the benefits of intermittent fasting believed to include everything from improving metabolism to decreasing inflammation and helping the body fight stress, it’s no surprise there are now so many different iterations of it.

The latest version is the 16:8 diet.

But before you jump aboard, here are few things you need to know before embarking on this form of time-restricted eating.

What is 16:8 intermittent fasting?

As the name suggests, the 16:8 diet is about embracing daily fasting and eating windows. “The diet involves eating only during an eight-hour period and fasting for 16 hours, other than calorie-free liquids,” dietitian Mark Robinson says.

Can you eat what you want during 16:8 intermittent fasting?

Following the 16:8 diet isn’t an excuse for an unchecked approach to what’s on your plate. “The diet encourages eating balanced meals within this time frame,” says dietitian Milly Smith, of Dietitians Australia.

If your aim is to lose weight, that means making wise food choices, because “if high energy/discretionary foods or high-energy drinks are consumed in this window it can negate this effect”.

How many meals should you eat on the 16:8 diet?

There is no strict rule on how you break it down, but experts say it is generally not advisable to have just one large meal in the eight-hour window.

Milly says approaches include skipping an entire meal and instead eating only two meals, or having three lighter meals spread out across the eight hours.

What to eat on the 16:8 diet

Mark advises aiming for a protein such as meat and fish, along with healthy fats such as nuts and seeds and high-fibre choices like fruits, vegetables and grains.

Pros and cons of the 16:8 diet

“For some people, eating in a smaller window can help them achieve an overall calorie deficit and lose weight,” Milly says.

But she adds that “the evidence for the sustainability of these benefits is still varied”.

Experts caution this eating pattern will suit everyone.

“Some people can find that they end up eating bigger volumes of food in the eating times, or choosing higher-caloric foods to ‘make up’ for what they are missing. Some people may also notice symptoms of nausea, light-headedness, and headaches,” Milly says.

Is 16:8 intermittent fasting safe?

“Yes, when done temporarily and not necessarily every day or for lengthened periods. Also, so long as you’re still consuming the right balance of nutrients,” Mark says.

Milly says the diet is best avoided by those who are trying to increase their weight, are underweight or have high energy needs (such as athletes).

Also it’s not advisable for those who have an eating disorder or have experienced it in the past.

Can you drink alcohol on the 16:8 diet?

It’s generally advisable to avoid alcohol or keep it to a minimum.

Due to its high energy levels, Milly says consuming alcohol may affect the amount of weight lost.

How long will it take to lose weight on the 16:8 diet?

“Everyone will respond differently depending on how much weight there is to lose in the first place (and factors such as) age, gender and activity level,” Mark says.

Should you ease into 16:8 intermittent fasting?

If you decide to follow this diet, Milly advises seeing a dietitian first.

“(This will allow you to) work out a pattern and food choices individualised to your needs/goals,” she says.

Can you switch to 16:8 permanently?

“(Doing it) temporarily as a shock to the body is best. Simply to break through a plateau and create some extra results then revert to a more sustainable and balanced meal and snack timing structured meal plan,” Mark says.

Written by Tania Gomez.