Intermittent fasting for weight loss has become very popular in recent times as a means to lose or maintain weight…. but does this diet really work?
Here our nutritionist gives you the facts and answers the most common questions. Read on so that you can decide if you’d benefit from intermittent fasting to meet your weight loss or weight maintenance goals.
- What is Intermittent Fasting?
- Rules for Intermittent Fasting
- Do you get results and maintain the weight loss with Intermittent Fasting?
- Does Intermittent Fasting work for weight loss?
What is Intermittent Fasting? How does it work for Weight Loss?
Intermittent fasting is an umbrella term for three different types of diet.
- Firstly, is alternate day fasting where you alternate all week between fast days (500kcal) and feast days (your normal diet).
- Secondly is the 5:2 diet where you fast 1-2 days a week and have 5 feast days.
- Finally, time restricted feeding is where you eat during a 4-12-hour window in a day.
Alternate day fasting style Intermittent Fasting
Calories consumed of fast day : 500
Non-fast day : Normal Diet
Time Restrictions : None
Alternate day fasting has been around for a long time. This style of intermittent fasting does not specify any special foods and lets you eat your normal diet on the non-fast days.
On the fast day, you are asked to restrict your diet to 500 kcal. This diet does not specify which foods should be consumed on the fast day or how you should spread the day out. Most people end up having a single meal through the 24 hour period. A typical 500 kcal day would possibly not give you enough energy or nutrients. Restricting your food intake every other day without the supervision of a healthcare professional can lead to a non-nutritionally balanced diet and so it not recommended.
5:2 Diet style Intermittent Fasting
Calories consumed of fast day : 500 for women and 600 for men
Non-fast day : Normal Diet
Time Restrictions : 2 fast days
The 5:2 diet has limited evidence in favour of its effectiveness. When compared to other weight loss diets it yields similar results.
On the fast day some people find consuming 2 large meals or 3 small meals easier with low calorie liquids like black tea or coffee without sugar during the day.
On the non-fast day, the 5:2 diet does not restrict any foods but allows you to consume your normal foods and you need to be careful not to overindulge during the non-fast period of intermittent fasting.
However, some people find the diet easier to follow due to just two days of restricted eating. It has also been shown to reduce body fat, insulin resistance and other chronic diseases.
It is important to note that fasting is not suitable for everyone, some people may feel dizzy, be irritable or have difficulty concentrating. It is also essential to maintain a nutritionally balanced diet on both feasting and fasting days.
Time Restricted Feeding style Intermittent Fasting
Time Restrictions : Eat only during 8 hour period
Calories consumed : Normal as per your goal
Arguably the most popular at the moment is time restricted feeding. One benefit of the time restricted feeding is that you don’t count calories.
One of the most popular eating windows is an 8h window, where you only eating between 10am and 6pm. During the window you can consume as many calories as you like.
Some people try and follow this style of intermittent fasting by skipping breakfast. This style could lead to over-eating during lunch and then a mid-afternoon slump follows.
There have been very few studies in humans for weight loss achieved by time restricted feeding. However, in one study with a 10h feeding window on average the participants ate 300-500 kcals less by restricting their eating window. This wasn’t intentional and could translate into weight loss if the activity levels remain high.
In another study with an 8h feeding window participants lost on average 6 pounds after 3 months and it was deemed to be a sustainable diet.
Does Intermittent Fasting work for weight loss?
Overall is fasting better for weight loss than the traditional diet of calorie restriction?
A yearlong study along with other studies has shown that fasting and calorie restricted diets produce similar weight loss results.
It’s also important to remember all weight loss diets will show the most weight loss within the first 3 months. The results of weight loss start diminishing due to the body’s metabolic rate adjusting to the lower intake.
However, if you are looking to lose weight in a healthy way and you find the 5:2 diet or time restricted feeding an easier way to do this then you could try this diet to see if it suited you.
Just remember on the days you can ‘feast’ it’s important to still consume a healthy balanced diet and don’t overindulge and you make sure to drink enough water during fasting periods.
Intermittent fasting style diets are not suitable for pregnant women, lactating women, people with disordered eating, shift workers and people who frequently snack. If you have any health issues you need to consult with your doctor before you try intermittent fasting.
Follow a Healthy Diet Plan for balanced diet as per your calorie requirements to get all the required nutrients.
Conclusion
Intermittent Fasting style diets ask you to restrict either the times to eat or reduce calories you eat on certain day. There are three different types of intermittent fasting diets – ‘alternate day fasting’, ‘5:2’ and ‘time restricted’.
All these yield some short term results but must be practised under the guidance of a qualified nutritionist or healthcare professional.
