The 16:8 diet has been one of the most popular diet plans we've seen in years - and with good reason.
The 16:8 plan – also called the 8-hour diet – is an easier and more consistent way of fasting that avoids those two notorious days of hunger found in other popular intermittent fasting plans.
Sports Scientist Harry Aitken tells GoodtoKnow, “Intermittent fasting is a dietary technique in which all food is consumed within a relatively small window of time. Fasting is going for a significant period of time without eating, and intermittent fasting simply brings in a small window of time where you are able to eat.
“Intermittent fasting has been popularised by religious festivals such as Ramadan and Yom Kippur, where for religious regions people must fast during certain times. Studies have then gone on to confirm weight loss and fat.”
Other ways to do intermittent fasting, like the 5:2 diet that limits calorie intake, have found fame in the last few years as everyone from celebrities to tech moguls and Instagram influencers have pushed the benefits of plans such as these.
One such supporter of the 16:8 intermittent fasting plan is Hollywood icon, Jennifer Aniston. In an interview with the Radio Times, Jennifer revealed that she’s a big fan of intermittent fasting in general but specifically this plan. “I do intermittent fasting, so no food in the morning.” She said, “I noticed a big difference in going without solid food for 16 hours,”
However, there are naturally upsides and downsides to every diet and the best way to lose weight is to moderate calories and do more exercise. So before starting on any weight loss plan, it’s best to consult your GP who will be able to advise the best course of action for you.
What is the 16:8 diet?
The 16:8 diet is a type of intermittent fasting done during a certain time frame to achieve better health or to help people lose weight.
For 16 hours everyday, you consume nothing but water, coffee, tea and other unsweetened drinks. Then for the other eight hours of the day, you can eat all your meals and snacks.
The diet stems from the book 8 Hour Diet by author David Zinczenko and editor-in-chief of Men’s Health Peter Moore, who suggested that a longer fasting time between eating gives the body the time it needs to process the food and burn away extra fat.
How does the 16:8 diet work?
The 16:8 diet works on an hourly basis. So each day you can eat within an 8 hour time frame and fast for the remaining 16 hours. The best part? You don’t have to restrict yourself to 500 calories at all – as long as you eat healthily in your 8 hour time frame, you’ll see the weight drop off.
Experts say that the 16.8 diet restricted schedule gives our bodies the chance to process the nutrients stored in foods and burns away calories. Plus, you won’t go hungry like you do on those two fasting days on the 5:2 either.
As Tom Jenane, nutrition and fitness expert explains, “The 16:8 diet is a brilliant form of intermittent fasting that has proven results in a number of cases.”
Even the celebs are getting involved. Hugh Jackman reportedly used the 16:8 diet to get in shape for his Wolverine films (it’s even been named The Wolverine Diet!) and Jennifer Love Hewitt is also said to be a fan.
When can I eat on the 16:8 diet?
The 16:8 diet is a fasting diet that, for most of it, you actually sleep through (phew!) You can pick an 8 hour window to suit your day – so it could be between 10am – 6pm or 11am – 8pm, for example. Plus, you can still drink tea and coffee outside of those hours too, so it’s not just water!
Most people choose to fast through the night, and opt to eat their first meal at about 12pm in the middle of the day.
Tom says, “The most common hours adopted for the eating period is 12 till 8pm. The reason for this is because people aren’t normally that hungry in the morning, you don’t want to be consuming too many calories during the evening and this allows us to eat our lunch and dinner as well as a snack.”
What can you eat on the 16:8 diet?
This diet isn’t suggesting you cram all the food you can into 8 hours. But you do need to make sure you’re eating a balance of fat busting and health boosting foods. Experts have suggest making sure you get a balance of lean meat, eggs, dairy, vegetables, nuts and beans each day. It really is that easy!
Tom said, “Many fail by packing in too many calories into the 8 hour period, often trying to get some in before the 8 hours ends. You should still be following a strict diet with a complete nutritional breakdown, to ensure you are consuming a targeted number of calories, not to mention macro nutrients and ensuring you’re not consuming too much sugar.”
Try sticking to the following foods on the 16:8 diet:
- Whole grains: Ones like rice, oats, barley, wholegrain pasta and quinoa will keep you fuller for longer.
- Protein: Meat, poultry, fish, eggs, nuts and seeds will keep you full.
- Fruit: Apples, bananas, berries, oranges and pears will offer good vitamin sustenance.
- Vegetables: Broccoli and leafy greens are especially good for making sure you’re eating enough fibre.
- Healthy fats: Olive oil, coconut oil, avocados.
How much weight can you lose on 16:8 diet?
To lose weight on the 16:8 diet, it’s important to match the fasting with healthy eating and exercise. If done so correctly, there’s a typical weight loss of around seven to 11 pounds over a ten week period. This is according to a review of 40 different studies published in Molecular and Cellular Endocrincology who found that on average, someone weighing just over 90kg would lose 5% of their total body weight in the ten week period.
A 2018 study published in the Journal of Nutrition and Healthy Eating revealed that the 16:8 diet plan can help people lose weight, without having to count calories as the 8-hour fast produces the same kind of calorific restriction and weight loss.
However, whether there’s a distinct weight loss advantage achieved on the 16:8 diet compared to other diets remains to be seen. Some studies have demonstrated that there’s almost no difference between people who do intermittent fasting compared those who count calories and cut back.
How often should you do 16:8 intermittent fasting?
Unlike other intermittent fasting diets, each day of the 16:8 works independently to the other days. This means that you can do anywhere from one day of intermittent 16:8 fasting to seven days a week, depending on your goals and the advice from your GP.
Evidence differs, however, on whether it’s healthy to do intermittent fasting all the time for a number of reasons. While one study suggests that fasting helps your vital organs by giving metabolic functions a break, other research suggests the fasting can lead to an increased level of cholestrol and can lead to feelings of nausea, along with causing spells of low-blood sugar and dehydration.
Are there any health benefits?
For some looking to lose weight quickly for health-related reasons, fasting is a good (but intense!) way to go about it. As Eve Mayer, author of Life in the Fasting Lane
“Being overweight is a cause of many diseases, such as heart disease, stroke and cancer,” says Eve Mayer, author of Life in the Fasting Lane. “Losing weight increases high-density lipoprotein and lowers triglyceride levels, which helps reduce the risk of those same diseases.”
But the 16:8 diet is not just about losing weight.
Improved heart health
A study by New England Journal of Medicine has shown that regular fasting is linked with a longer life and lower incidence of heart failure in heart patients. Even just one day of fasting a month – when done over a lifetime – can have a profound effect on heart health.
A regular circadian rhythm
Your internal body clock regulates tiredness and alertness over a 24-hour period. Research suggests intermittent fasting may strengthen our body’s circadian rhythm, as overeating can cause interrupted sleep, therefore helping us to sleep better.
Reduce stress and improve mental health
The 16:8 diet help reduce cortisol levels (that means less stress!) and help reduce inflammation. Plus, since you won’t be dealing with hunger for two days a week, it’s better for your mental health.
Those who’ve tried the 16:8 diet say how much more productive they are during fasting hours, spending less time stressing over food and more time channelling their energy into other beneficial tasks throughout the day.
While it’s important to remember that what works for one person’s lifestyle won’t work for another, intermittent fasting with the 16:8 diet has given some people some real success – in all areas of life.