5:2 diet – The beginner’s guide

The 5:2 diet is currently the most popular and well-known form of intermittent fasting. Also known as The fast diet, after the book of the same name that helped popularize the fast. 5:2 is a very beginner-friendly form of intermittent fasting, which offers many scientifically-backed benefits for practitioners.

The diet is easy enough to explain. Basically, you divide your normal seven-day week into 5 “normal” days and 2 fasting days – 5:2. Even though you don’t fast very many days of the week, your body will still undergo positive metabolic and physiological changes from those days you do fast.

Health benefits of the 5:2 diet

5:2 is a form of intermittent fasting, and therefore it shares many of its benefits with other types of IF – with some important characteristics of its own.

We wrote an article that goes in-depth about the many benefits of IF, but here is a shortlist.

• Increased and accelerated weight loss
• Improved metabolism
• Increased insulin resistance, which helps protect against and improves symptoms of type-2 diabetes.
• Improved heart health
• Reduces inflammation
• Protects against alzheimers

This list is not exhaustive, and IF has shown potential for even more benefits than this. 5:2 can also claim all of these among its potential benefits.

Intermittent fasting is often compared to the bog-standard method of losing weight: caloric restriction AKA eating less. Research has suggested that intermittent fasting has some characteristics that can make it more attractive than caloric restriction. It might be easier to follow for some people, and the results might last longer.

A few studies specifically target 5:2 dieting. One of them found that subjects had a marked increase in the levels of ketones in their bodies. Ketones are alternative fuel sources to carbohydrates. This basically means, that their bodies were burning fat as an alternative, and not just digested sugars. This enhanced ability to burn fat is a hallmark of intermittent fasting, and one of its most popular benefits.

Although you can eat whatever you want when you fast, nutrition is still important. One study looked at the dietary composition of people following the 5:2 diet. These people naturally cut down on carbohydrates and increased their consumption of fibers during their fasting days. This is a diet that is generally more helpful in inducing ketosis and helping weight loss.

Getting started with 5:2

Getting started with 5:2 is almost as easy as explaining what the “diet” consists of. First, you simply pick two days of the week that aren’t consecutive. Then you restrict your intake of calories on those days to 500~600 calories – easy!

See, the 5:2 diet is not really a “diet”, but a form of intermittent fasting. This means that you can essentially eat whatever you want, also on your fasting days.

This, of course, makes it so you don’t have to plan any fancy dishes or meal prep anything – you can eat (almost) like you are used to.

That said – if you eat junk food, candy, or other low-quality foods, your weight loss might not be that impressive, and you might even gain weight.

On fasting days, it is important to drink plenty of water, to avoid fatigue, headaches, and other side effects.

What to eat on fasting days?

As already said, you can eat whatever you want on the fasting days – no foods are restricted.

It might sound easy, but everyone is a little different in how they best handle fasting. You might get very hungry quickly, and therefore need to eat more, smaller meals. Or you might want to save yourself for a single, filling meal. Or perhaps, there is one snack or food that is all you need to get through a fast.

We recommend experimenting with your fasting days, to find what is optimal for you. After all, the freedom of intermittent fasting is supposed to be a benefit – so be sure to use it to mix things up.

When you are fasting, it’s important to make every calorie count. Your recommended daily intake of calories is 2000, so you will only be eating a quarter of that, which can be a tough experience.

Here is a trick. Just because you can only eat 500 calories, doesn’t mean that you cannot eat filling portions. The trick is to eat low-calorie foods instead of blowing your calorie budget on a few high-calorie foods. We recommend low-calorie foods like:

• Fresh vegetables
• Berries
• Yoghurt
• Fish
• Eggs
• Soup

Although you can and should experiment with your eating habits during fasting days, most people have the best results with many smaller portions. By spreading out your eating, you tend to avoid spikes in your blood insulin levels. This can prevent you from becoming lethargic, or extremely hungry

When to eat?

A study looked at the effect different eating periods had on the 5:2 diet. Surprisingly, it showed that those who ate earlier in the day experienced had the same energy expenditure as those who ate later, but they were less hungry.

The researchers speculated that aligning your fasting eating period with your circadian rhythm helped decrease hunger, which could lead to a better and easier weight loss.

Weightloss and 5:2

The way that 5:2 and other types of intermittent fasting help you lose weight is two-fold. First of all, when you fast your body, you help it go into Ketosis. Ketosis is a metabolic state, in which you burn ketones instead of sugars (carbohydrates). The ketones are made up of your stored reserves, which means they will burn whatever fat you have on your body.

The second is, that fasting will make you less hungry. Even if you eat normally on days, or even have a blowout two, like a party or a night out with drinks, your fasting days will still help you stabilize your weight. During the fasting days, the levels of insulin in your blood fall, which helps trigger ketosis. This should also make your appetite smaller during your normal days, which will make it easier to avoid overeating.