The 5:2 intermittent fasting (IF) diet, also known as the The 5:2 Fasting Diet or just “fast diet”, has become quite a popular diet plan in recent years and has been a common topic of research amongst nutritionists and doctors.
A BBC Horizon’s documentary on the 5:2 diet featuring Dr. Michael Mosley a trained doctor & a medical journalist of repute is credited with popularising this diet. He experimented various methods of dieting on himself, starting with a full fast and eventually arriving at a ratio that worked for him: 2 days of partial fasting (lesser calorie intake) along with 5 days of normal eating. It resulted in a 5 week loss in weight of approximately 6-9kgs and a number of blood tests showing remarkable improvements in glucose levels and cholesterol, among other things.
Just like Dr. Mosley, many people around the world are seeing excellent improvements in their health as well as significant weight loss, by following this intermittent fasting diet.
One rationale for the popularity of the 5:2 diet is that on most days of the week, it allows a certain amount of flexibility on what you can eat, in contrast to other low calorie diets which puts a major restriction on the food intake. Also, the eat normal for five days & diet for two days, can potentially help you to lose weight, become healthy, and even live longer. This is because by reducing your calorie intake intermittently, instead of all at once, your body goes into ‘repair mode’ and not ‘starvation mode’. This repair mode helps the body to restore damaged cells, which uses more energy, whereas starvation mode triggers your body to store fat.
To get a better idea of this, here are the answers to a few frequently asked questions!
How does the 5:2 diet work?
The 5:2 Diet plan is easy to remember. For five days of the week, you can eat normally, as you always do (2,000 calories a day for women and 2,500 calories for men) and for the other two days, you must restrict your calorie intake to just 500 calories for women and 600 calories for men. We make healthier choices and savour every meal on fasting days, as we are more aware of what we eat and how much we eat.
The best part is that we get a feeling of freedom from cravings for junk or high-calorie food and we also feel an increase in energy.
How does the 5:2 diet effect our body?
Many studies conducted have resulted in most overweight and obese people to lose weight successfully with this diet.
Insulin levels, leptin and ghrelin are important hormones that shape our appetite and send out hunger signals. Obese people often have low leptin sensitivity and insulin, which means that they are hungry all the time and they don’t burn fat but instead store it. Intermittent fasting may help to stabilize leptin and insulin levels. Moreover, insulin sensitivity is not only crucial for weight loss, but it is also a key factor for reducing the risk of developing diseases like Type II Diabetes, cardiovascular disease and many others.
How do I get started?
Although some people find it easy to adapt to various diets, most of us find it difficult and quite challenging.
To start off initially, you could set a target date by when you would like to lose a certain amount of weight. But you must remember to keep realistic targets.
You could ask a few friends or family members to join you, to keep you motivated.
One more tip is that, you could fix your regular days and fast days before you start the diet, ensuring you to plan on what you could eat on your fast days. For example: Mondays, Wednesdays, Fridays, Saturdays and Sundays can be normal days. Tuesdays and Thursdays allotted for fast days.
What can I eat on a fast day?
Hence, the basic principle is to eat foods that are high in protein and fibre, as these are the most satisfying. That includes vegetables, especially the leafy green veggies (organic is better), small quantities of meat and fish (they must be roasted or baked and not fried) and ensure you drink a lot of water.
Avoid foods that are heavy in carbohydrates or anything rich in sugar on fast days.
What is the ideal frequency of meals on a fast day?
Some evidence shows that it is better to stick to two small meals in a day. So maybe you can do a combination of breakfast, lunch and dinner, whichever is convenient for you.
Can the fast days be consecutive days?
Yes, the fast days can be consecutive. In fact, many people prefer fasting like this.
But, for beginners, it is better to split the fast days in the week. This is because, it may be too tiring to start off fasting 2 days in a row and the body would not have adapted to the diet regime.
Once you get a hang of it, you can plan your fast days of the week according to your convenience.
Who shouldn’t fast?
Those people with Type 1 or Type 2 diabetes, or other chronic or acute diseases must consult their doctor/specialist before making any lifestyle changes (such as dieting) so they can advice you on it.
Also, pregnant women & breast feeding mothers, children and teenagers, people recovering from surgeries and people with eating disorders must avoid fasting.
What are the benefits of this fast?
- Your cognitive function may be enhanced which can help to prevent conditions like Alzheimer’s and dementia. With a diet that includes good fats, adequate protein and low carbohydrates, it can be effective in reducing epileptic seizures and in increasing learning and memory ability.
- Initial studies suggest intermittent fasting may have the ability to increase lifespan.
- It may reduce your risk of developing chronic diseases such as Type 2 diabetes, among others.
- It is not as restrictive as other diets. You can eat anything you feel like, just ensuring you are within your daily calorie limit. This is one reason why people stay motivated to continue the diet as there is flexibility.
- You get to choose which days of the week you are fasting and hence it’s easier to make it part of your lifestyle.
Will I experience any side effects?
Most common side effect is hunger, especially for beginners. Some people feel a disruption in their sleep patterns. For this, you can keep aside a few calories for a midnight snack or a glass of milk. Dehydration has also been faced by few people who have done this diet and suffer from headaches. To ensure this doesn’t happen, you must drink a lot of water.
Can I exercise on a fast day?
There is good evidence that people who exercise in the fasted state burn more fat. In one study men who exercised before breakfast burnt more fat than those who exercised afterwards. Exercise can also be a useful distraction if you begin feeling peckish. Don’t, however, attempt to do a lot of endurance training on a fasting day and if you feel uncomfortable, stop.
Will it put me in starvation mode?
The initial response of your body to a reduction in calories is to increase your metabolic rate. This is because, in our hunter-gatherer past, survival in times of food shortage would have depended on our becoming more active, going out to hunt and look for food. Only under conditions of extreme calorie deprivation, when we have been for weeks without enough food and our body fat has fallen dramatically does the body go into “starvation mode”. Intermittent Fasting is not the same as crash dieting. Starvation mode does not happen if you cut your calories for a day!!
Once I reach my target, how can I maintain it?
Once you’ve achieved your goal, you can stop with the 5:2 diet and maybe continue to fast on just one day of the week and eat normally the rest of the days. This will ensure you to maintain your weight.
How can I make 5:2 diet a part of my lifestyle?
Once you get used to the diet plan, you will be able to easily make it part of your current lifestyle.
Also, since the diet is flexible, you can choose the days you want to fast and is highly convenient.
If you are feeling fatigued or weak on fast days, consult a specialist.
Don’t forget to weigh yourself, say once a week, to keep you motivated to continue. If you are not losing weight, do not lose hope. Try not to overeat on regular days and keep tabs of calorie intake too.
Apart from the 5:2 diet, there are other types of Intermittent Fasting, where basically the ratio of fasting to eating periods vary.