Intermittent fasting 101

Intermittent fasting 101

While we know that all you need for a ‘beach body’ is a body that you take to a beach, there’s no doubt that summer is a time when many of us want to shed a few pounds.

In the endless quest to control the calories, the intermittent fasting (IF) technique is a popular front runner. So what is IF and does it work?

1.     WHAT IS INTERMITTENT FASTING?

IF involves days of normal eating interspersed with ‘fast’ days of extremely restricted calorie intake. On ‘fast’ days the dieter should eat no more than 25% of their normal calories. For most people this is about 500-600 calories.

The 5:2 pattern is the best known form of IF, with the two fast days being non-consecutive. Another variation is alternate day fasting (ADF) which advocates no restrictions on eating on normal days.

There are also daily variants which limit the times when eating is allowed.

2.     WHAT IS THE EVIDENCE BEHIND IT?

The NHS has summarised various studies and reviews into the effectiveness of intermittent fasting. There have been no universally recognised clinical studies. There is also no conclusive evidence that the time at which you eat makes any difference to how calories are handled.

However, many believe that the ‘feast-famine’ model is how human beings are designed to live, going back to our hunter-gatherer days. Hence IF is simply working with the natural rhythms of our bodies.

Perhaps the simplest answer is that the heavy restrictions on fast days lead to an overall reduction in calorie intake. So IF is a structured way of eating less, and that may be why it works for many people.

3.     ARE THERE ANY RISKS?

Some people find that hunger on the fast days affects concentration, efficiency and reaction times. So fasting is not compatible with demanding jobs or driving. Hungry people can also be grumpy, so fast days can be a risk to relationships. If you're looking for an alternative fasting approach that is guaranteed to have ZERO risk, you could try this reversed water fasting trick.

Food and eating should be part of the pleasure of life, but a long-term regime such as IF may mean that food starts to rule life. Keep a sense of proportion (and don’t be a diet bore!)

IF is not suitable for diabetics, pregnant women, children and people with other long-term health conditions.

4.     CAN I MAKE IT WORK?

The top tips to make IF work are:

  • Keep the ‘normal’ days sensible – they are not a licence for a blow out!
  • Ensure that fast days have filling balanced meals. This reduces the chance of over-eating.
  • Don’t let it rule your life.

IF could well be a good way to kick start a lifestyle change. We know that we need sensible eating and regular exercise – keep an open mind, look after your health and see what works for you.

 


The Author

Jessica Ambrose

Jessica is a fitness writer who loves boxercise, yoga, pilates, weight training and long distance running..

Comments

Pete R.
19 August 2015

Pete R.

Any day where I can't eat much is a bad day!

John C.
14 August 2015

John C.

Emma C is on to it... It's a good plan for busy people(not busy from exercise though). It's really easy to fast on busy days where in truth, you usually run around all day on a digestive biscuit. Work all day, come home late, shower, quick bite and collapse in bed... easy. Some weeks I didn't even notice that I had fasted 3 days, 4 even? It's about lifestyle management and also the correct eating plan for the goals you want? I lost loads of weight and feel much better for it. If you have a busy weekly schedule, no willpower required.

Olivia C.
12 August 2015

Olivia C.

I think if I fasted on an exercise day I might just keel over. I know this works for some, but I say just eat sensibly all week rather than skipping meals on two days.

Clare R.
10 August 2015

Clare R.

I also know intermittent fasters, and it certainly isn't pretty mood-wise at times! 'grumpy' is a mild description!

Emma C.
10 August 2015

Emma C.

I sort of do this when I've got working days twice a week as I just get too busy to eat. I just tend to eat fruit for breakfast, then lunch is mostly missed apart from possibly some veg sticks and hummus, and dinner is a proper meal. SO not many calories during the day. Bot sure if this counts as really 5:2 though.

Joseph M.
9 August 2015

Joseph M.

This isn't a good idea in my book - it simply isn't sustainable long term and those fast days can really effect your mood/concentration - believe me I've lived with someone giving it a shot! It's not worth the aggro when a sensible diet can have the same effect.

craig t.
8 August 2015

craig t.

Similar to what Mike says - if you don't actually need to lose weight but aren't eating for 2 days PLUS exercising, then the 5 and 2 diet wouldn't suit you.

Sarah L.
5 August 2015

Sarah L.

Freya, I think you've hit the nail on the head with the problem with 'diets'. It needs to be a lifestyle change or they will fail.

Freya W.
5 August 2015

Freya W.

I know loads of people that have done the 5:2, and although they seem to get results really fast, the second they stop the diet the weight goes back on. I think for it to be sustainable you have to be exercising as well, so I think that it's right to use it to kickstart a healthy lifestyle, but not to sustain long term.

Mike D.
5 August 2015

Mike D.

I believe it's a very healthy thing for your body but I also believe it's not so good if you're exercising a lot. how can you sustain your body's energy if you aren't eating a couple of days a week and don't need to lose weight?

Would you like to post a comment? Please register or log in.

Log In Register

Share this

Subscribe

Popular Posts

By continuing to use our site, you are agreeing to the use of cookies. You can change this and find out more by following this link.