7 Fat Loss Benefits of the 5:2 and Fast 800 Diets by Michael Mosley

Are you considering trying intermittent fasting to lose weight? Doctor James O'Donovan, MBBS, specializes in aging and regularly shares videos on promoting longevity. In one of his viral videos, he discusses a popular weight loss method, 16:8 intermittent fasting, going over everything you need to know about the trending eating style.

What Is Intermittent Fasting?

“Intermittent fasting is when you alternate between periods of eating and fasting. This type of eating is often described as ‘patterns’ or ‘cycles’ of fasting,” he writes in the caption of the clip. “Intermittent fasting isn't about starving yourself — it's about cutting way back on calories for short time periods. The belief is that your body becomes satisfied with smaller portions while also reducing cravings for unhealthy snack foods. That is, as long as you maintain a healthy diet while trying it all out.”

16:8 Fast for 16 Hours and Feast for 8

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16:8 Intermittent fasting is “a popular type of intermittent fasting that involves fasting for 16 hours and an 8-hour eating window,” he writes. He goes on to explain what it is, “what time windows you might want to choose for your fast, food groups to consider, and benefits and drawbacks of intermittent fasting.”

It’s Not About What You Eat, But When You Eat

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“Many diets focus on what to eat, but intermittent fasting is all about when you eat. With intermittent fasting, you only eat during a specific time. Research shows fasting for a certain number of hours each day or eating just one meal a couple days a week may have health benefits - for example, for losing weight and for better control of diabetes,” he says.

More Details About Intermittent Fasting

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“Intermittent fasting involves limiting your daily food intake to a certain window of time. Now, one of the most popular types of intermittent fasting is a diet that's called the 16 eight intermittent fasting diet,” he continues. “Essentially, this involves limiting your intake of food and drinks, which contain calories, to a set window of eight hours a day. Now, for the remaining 16 hours, you abstain from food and drink. However, you are still allowed to drink water and other non-calorie beverages, such as plain coffee or tea. Importantly, you can repeat this cycle as frequently as you like, from just once or twice a week to every day, and it will all depend on your personal preference as well as what fits in with your lifestyle.”

It’s Easy to Follow and Is Less Restrictive Than Other Diets

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“While other diets often set out strict draws, 16 eight, intermittent fasting is easy to follow, and it might provide measurable results with minimal disruption to your diet,” he notes. “It's generally considered less restrictive and more flexible than many other diets, and it works well with most lifestyles.”

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Choose a Time Window That Works for You

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It’s key to choose a time window that works for you. “You should begin by picking an eight-hour window and limiting your food intake to that time span. Now, this is obviously going to depend on your lifestyle, but some popular eight-hour time windows to eat are from 7:00 AM to 3:00 PM, 9:00 AM to 5:00 PM, 12:00 PM to 8:00 PM, as well as 2:00 PM to 10:00 PM,” he says. “Basically, what I'm trying to convey by this is that there is no one fixed way to do things. The best thing to do is that when you're starting out, try to experiment and pick the timeframe that best fits your schedule.” He also recommends setting a timer for the start and stop times of your feast period.

Eat Nutritious Whole Foods

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“Now we've discussed the time window. Let's just discuss some of the food and meal plans now to maximize the potential health benefits of any diet,” he continues. “It's important to stick to nutritious whole foods and beverages during your eating period. Filling up on nutrient-rich foods will basically help you round out your diet and support a healthy weight. Trying to balance each meal with a variety of whole foods can include things like fruits, such as apples, bananas, berries, oranges, pears, or tomatoes, and vegetables, so things like broccoli, brussels sprouts, cauliflower, cucumbers, and leafy greens. Things like spinach and kale, as well as whole grains, are really important.”

He also recommends barley, buckwheat, quinoa, rice, and oats, healthy fats like olive oil and avocados, and protein sources, including eggs, fish, meat, poultry, nuts, and seeds.

And Stick to Zero Calorie Drinks

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He also tackles the topic of beverages. “In terms of drinking, I would just encourage you to drink water and avoid any calorie beverages,” he says. “These are things like pops and sodas. I would just stay very clear of those.”

Avoid Ultra Processed Foods

“It's important also to avoid ultra-processed foods, things like packaged snacks, deep fried items, sugary drinks, and most frozen meals,” he continues. “These foods are often full of bad sugars and preservatives, which are going to spike your blood sugars quickly, and they're going to make you feel more hungry. And ultra-processed foods have actually been linked with a whole host of negative health outcomes, so things like type two diabetes, high blood pressure, certain cancers, and even dementia.”

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Here Are the Potential Benefits

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He goes on to discuss the potential benefits of this diet. “The first potential benefit of restricting your eating window to a few hours a day is that you can cut your calorie intake over the course of the day, which may, in turn, contribute to weight loss. For example, one review of the scientific literature on intermittent fasting found that it's in 11 of the 13 studies on intermittent fasting. It was reported there was statistically significant weight loss in participants,” he says. Another benefit? Improving blood sugar.

“Intermittent fasting has been shown to reduce fasting insulin and blood sugar levels, potentially decreasing your risk of diabetes. Now, if you've got type two diabetes, intermittent fasting might be an effective intervention, but you should speak to your own doctor before embarking on this diet to see if it will work for you.”

Here Are the Potential Drawbacks

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He also discusses potential drawbacks. “The first thing to state is that it's important that if you decide to embark on this type of fasting, that you do it gradually and you consider stopping or consulting your doctor if you've got any concerns or you experience any negative symptoms,” he says. “One of the other downsides is the potential for overeating as well as potential weight gain. That's because restricting your intake to just eight hours a day may cause some people to eat more than usual during the eating periods in an attempt to make up for the hours spent fasting. Now, this may lead to weight gain, digestive problems, and unhealthy eating habits.”

He adds that some people experience short-term physical symptoms. “These include things like hunger, weakness, and fatigue, although these often subside once you get into a routine,” he says.

Fasting Doesn’t Necessarily Lead to Weight Loss

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“Now, interestingly, current research doesn't suggest that intermittent fasting leads to any more weight loss than typical diets that recommend overall calorie restriction. Both eating patterns may lead to moderate weight loss. Now, suppose weight loss is your primary goal. In that case, you might prefer to lower your calorie intake instead of fasting intermittently to prevent the overeating that can occur when restricting intake to certain time windows,” he says.

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Here Are His Top Tips

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He goes on to reveal his top intermittent fasting tips. “If you do want to start this, you should start with just one to two days a week and see if it works for you,” he says. “You should try different timings to see which fits your lifestyle. If you've got a long-term health condition, you should first consult your doctors to discuss whether or not this is the right type of dieting for you. This is important if you're taking any medications if you've got diabetes, low blood pressure, or a history of disordered eating. It's also important not to view 16-8 intermittent fasting as a substitute for eating a balanced diet rich in whole foods. And similarly, intermittent fasting is discouraged if you're trying to conceive your pregnant or your breastfeeding.” And if you enjoyed this article, take advantage of these 15 Quick Ways to Lose Body Fat Percentage in a Week.

Are you considering going fast? Before you hop on the trending diet method, it’s crucial that you do a little research on the various types. Dr. Jason Fung is a specialist physician, nephrologist, and New York Times best-selling author of The Obesity Code, The Complete Guide to Fasting, The Diabetes Code, and The Cancer Code. In a viral YouTube video, he discusses “the different types of fasts that you can do because there's a lot of different variations that you can try then still get good results, and it's coming right up.”

Fasting Is a Period of Time You’re Not Eating

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“A fasting period is defined as any period of time that you're not eating. So, in the classic definition, you're really only allowed water. And if you take anything else by definition, that is breaking your fast,” he says.

There Are Various Reasons You Might Want to Fast

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There can be lots of different reasons you might want to fast, he continues. “You can try do it to lose weight, you can do it for controlling your blood sugars. There's lots of different reasons why you might fast, and in those circumstances, you can allow certain things into your fast that are going to make it easy.”

Different Methods Might Make It Easier to Sustain a Fast

Why should you consider trying a different fasting method? There are “different variations of fasting that you can try that might make it easier to sustain the fast and therefore get good results in terms of what you're aiming for,” he says.

1. The Classic Fast

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“The classic fast only allows water with nothing else, and there are lots of ways that you can still add some flavor to the water and still make it taste good,” he says. “So you can try lemon or lime, for example. You can squeeze lemon in and drop it in. There are lots of flavorful oils in the skin or the rind that can make it taste good. You can infuse herbs into it. So mint is very popular, and cucumber is very good. Then, you can infuse fruit flavors. So if you use something like strawberries, for example, you can cut them up, put them in water, let them steep overnight, and you'll get the flavor of the strawberry with very little calories.”

You Can Add Apple Cider Vinegar

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Apple cider vinegar is another thing you can add to water, “and while it's still just water only, it has a little bit of that tanginess,” he says. “Some people find it's very helpful in terms of suppressing hunger.”

2. Dry Fasting

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Number two is dry fasting, says Dr. Fung. “This is used classically in certain types of religious fasting, and dry fasting does not even allow water. So, the amount of time you can do it is limited. Certainly, anything over 24 hours is not recommended, and many people get thirsty long before that.”

While Dry Fasting and Metabolizing Fat, Water Will Be Released

“Taking something to drink often makes it easier to fast. So, some people find dry fasting a little harder, but surprisingly, some people find it easier, and there's a reason for that,” he continues. “When fat is being metabolized, it actually breaks down, and water is released. This is one of the reasons why bears, for example, will hibernate all winter and they're not drinking any water, so you might wonder how they're getting their, uh, water, why they're not getting dehydrated. And it's because the metabolism of the fat will actually release a little bit of water during fasting.”

This Makes People Urinate a Lot

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“What can sometimes happen is people may find that they're urinating a lot,” he continues. “As you fast, the insulin levels go down, and insulin tends to hold water within our bodies. So when we fast, that insulin level allows that water to come out. So some people get a lot of urine, and some people even get diarrhea, and they find it very bothersome. And in this situation that's where dry fasting for a short period of time might be very useful to make it easier for you.”

Some People Find Their Hunger Levels Drop During a Dry Fast

“The other interesting thing is some people find that their hunger is much less when they do a dry compared to a water only or a flavored water fast,” says Dr. Fung. “And if it works for you, there's no reason not to do it. But again, I stress that anything longer than 24 hours is not recommended because you do get dehydrated very quickly.”

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3. Tea Fast

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Number three is a tea fast. “So in addition to allowing flavored waters and waters, you also allow herbal teas and also teas with no other cream or sweeteners. So no artificial sweeteners, no artificial flavors, but green teas, black teas, oolong teas,” says Fung. “There are also other variations like herbal teas, which are not real teas because they don't have the tea leaf. They're herbs. So mint teas, chamomile teas, and cinnamon, for example, are all very good. There are other varieties that you can get now, like mushroom teas, which some people find very useful because they don't have any calories and have no effect on insulin.”

These Can Be Helpful for Weight Loss

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“As you fast, your body is going to metabolize the glucose in your body, so your blood glucose often gets better, and then you're going to metabolize fat. So you will find that you can lose weight, and the tea or the herbal tea may make it a lot easier,” he says.

4. Coffee Fast

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“The fourth variant you can try is allowing coffee. So black coffee is good, and it contains a lot more caffeine than tea,” he says. “So some people find it very useful. Also, a lot of people are very addicted to or used to having coffee in their system, so they find it very useful to maintain that normal rhythm when they're eating or when they're fasting. So coffee and a little bit of cream is okay; both teas and coffees, when it's hot, are great as iced variations as well.”

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5. Bone Broth Fast

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The fifth type of variation is bone broth. “Bone broth is clearly a type of food in that it has proteins, but it often has fats and some calories. However, the amount is very small. So while it's not a true fast, you can use it to help suppress hunger,” he says.

Because It Has Fats and Calories, You Might Be Able to Fast Longer

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Because of the fat and calories, “you can use it to go longer periods of time,” says Dr. Fung. “And by doing that, you can sometimes get excellent results in terms of blood sugars and weight loss. We recommend homemade broths using bone. If you don't want to use bones, you can use vegetable broths, but try to avoid canned broths that tend to have a lot of processing, bouillon cubes, MSG, and that kind of thing. It's better to make your own and use the bones, vegetables, and herbs. Some people also add some vinegar into the mix.”

6. Fat Fasting

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“The sixth type of fasting is fat fasting, and we talk about this a lot where we use high-fat foods,” says Dr. Fung. “Well, again, not a true fast does allow some people to do very well in terms of their weight loss.”

The Fat Suppresses Hunger

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“The fat really helps suppress the hunger, and because it's also very satiating and you can sometimes still lose a lot of weight on these high-fat diets, it is sometimes very useful,” Fung continues. “Bulletproof coffee is a type of fat fasting because you have the coffee and then usually a large amount of oil or butter or MCT oil. Therefore, it really classifies it as food. There's a significant number of calories there, and that can sometimes be very good. We have heard lots of people say they've done great on that.”

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7. 5-2 Fasting

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The seventh type of fasting is the five to two fasting, popularized by Dr. Mosley in the UK “and it has five normal days of eating and two days of fasting, which is not a true fast, but he allows 500 calories during that day of fasting,” he says. “So clearly, it's not limited by time, but on those two days, it's an ultra low-calorie day. And again, that is sometimes a great strategy for some people to use with a lot of success.”

8. Fiber Fast

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“The eighth type of fast is what can be sometimes called a fiber-fast, where you're just allowing very, very high fiber foods such as chia seeds, for example. So chia seeds, you can put them in some liquid, and they will bloom up form, form sort of a gel, and you can put a little bit of flavoring in that, and when you eat it, it makes you full, but there's a lot of fiber in there,” he says. “So it sort of takes up a lot of space and keeps you full. And if it allows you to do more of the regular fasting, then sometimes the net benefit is there.”

There Are Other Variations

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According to Fung, there are “lots more other ways to vary” fasting, “including the amount of time you're fasting, but these are ways you can change what is allowed during the fast. And by doing that, you might find that one strategy really works for you. And if it works, great, go ahead and use it. If not, you can change and try different other things.”

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The Key Is Finding Which Is Right for You

“The key is to see what works for yourself because we're all different. So give them all a try, and I hope you'll have the best of luck,” he concludes. And if you enjoyed this article, take advantage of these 15 Quick Ways to Lose Body Fat Percentage in a Week.