Though medical opinion on the efficacy of various diets is constantly evolving, in recent years, a host of neuroscientists, nutritionists and doctors have voiced cautious support for a specific, time-dependent diet; 16:8 intermittent fasting.
Whilst the word ‘fasting’ tends to evoke alarm bells in the sustainable, sensible eater, intermittent fasting (or ‘IF’) is intended to be more manageable in its approach, allowing the user to continue enjoying all food groups and achieving a balanced diet, but simply focusing on the timeframe in which they eat as a means of hacking the way their body burns through energy.
Though previously dismissed as a fad diet, – and the jury is still out on the 5:2 version – there is now increasing evidence to suggest that the 16:8 plan, particularly, can be useful in managing weight. Dr Deborah Wexler, via Harvard Health, suggests that ‘’there is evidence to suggest that the circadian rhythm fasting approach, where meals are restricted to an eight to 10-hour period of the daytime, is effective.’’
Mark Mattson, a neuroscientist with Johns Hopkins Medicine in Baltimore, tends to agree, suggesting in a new review in the Dec. 26 issue of the New England Journal of Medicine via WebMD, that ‘’The state of the science on intermittent fasting has evolved to the point that it now can be considered as one approach, with exercise and healthy food, to improving and maintaining health as a lifestyle approach.” Food for thought, indeed.
If you’re keen to learn more, then you’ve come to the right place; here are your questions on 16:8 intermittent fasting answered.
WHAT IS INTERMITTENT FASTING?
When people hear the term ‘fasting’, they tend to think about the rules of Ramadan where eating during the day is not permissible.
This isn’t what intermittent fasting (IF) is – it’s actually designed to be a little more manageable. The basis of IF is that you select a set timeframe to eat in which is generally less spread out across the day than a normal eating pattern of breakfast, lunch and dinner. Then, you only eat within this more narrow window, though it should be emphasised that normal healthy eating principles apply within this window.
For beginners, a 16:8 ratio is a good place to start. This means you’ll fast for 16 hours and eat your day’s meals during an eight hour window. There are different ratios to choose from, so if 16:8 doesn’t suit you, you can try something else instead, but this is generally considered the most common and most manageable division of time.
HOW DOES INTERMITTENT FASTING WORK?
When you’ve selected the timeframe ratio you’re going to fast for, the ‘rules’ are quite simple. For those following the 16:8 ratio, you might choose to eat between the hours of 10am and 6pm. This window of time will allow you to eat a late breakfast, a lunch and dinner, with plenty of time for snacking in between.
With IF, you don’t need to restrict foods or cut out specific food groups – you can eat what you want. It’s recommended that you try and eat a healthy, balanced diet, but you don’t need to worry about ‘cheat days’ or other dieting principles which may in fact be unsustainable and damaging in the long run.
When your eight hour eating window closes, you don’t eat until it opens back up again. It’s best to time the majority of the fasting overnight so that you’re not tempted by food; this will make it easier to follow through with the diet.
WHAT IS AN EXAMPLE OF AN IF DIET?
As mentioned, a 16:8 IF doesn’t require any specific dietary changes, but if you’re looking for a good example of something to follow, here’s what one day might look like:
- 7am – wake up
- 10am – drink a glass of water and eat a bowl of porridge with mixed berries and a side of granola
- 11:30am – drink a glass of water and eat a snack of two pieces of fresh fruit and yoghurt
- 1:30pm – drink a glass of water and eat a lunch of wholemeal pasta with mixed vegetables and salt and pepper chicken
- 3pm – drink a glass of water
- 4pm – eat a snack (this could be a treat snack like a chocolate bar and a piece of fruit)
- 5:45pm – drink a glass of water and eat a good size portion of Thai green curry with brown rice
This isn’t to say that your day needs to be structured exactly like this, but snacking in between meals and drinking plenty of water will ensure you satisfy your hunger and remain hydrated and healthy. You can eat whatever you want, when you want, but the above example gives you a good idea of how the 16:8 ratio could work.
The principles remain that you enjoy meals as normal, but your breakfast falls a little later than is traditional, and your dinner falls a little earlier than most people eat theirs.
CAN YOU EXERCISE WITH IF?
Of course! The NHS recommends that all adults should aim to be physically active everyday, and strive to enjoy at least 150 minutes (that’s two and a half hours) of moderate intensity activity a week or 75 minutes (an hour and fifteen minutes) of vigorous intensity activity a week.
That said, during periods of intermittent fasting it’s wise to time your exercise accordingly. For those who are comfortable exercising on an empty stomach, working out in the morning before your eating window begins is best. If you exercise well after fuelling, then working out after your eating window closes will likely suit you better.
It’s essential that you listen to your body when exercising to ensure that you’re not pushing yourself too hard. Should you begin to feel dizzy or weak, take a time out and drink a carbohydrate-electrolyte drink.
DOES IF WORK?
The question on everyone’s lips is does intermittent fasting actually work? A consensus has not yet been reached on that one, but some recent studies conducted have shown it to be a potentially effective tool in losing fat and retaining muscle when combined with exercise and healthy eating.
IS IF SUITABLE FOR EVERYONE?
That said, caution is recommended; the team at Harvard Health go on to say that ‘’people with advanced diabetes or who are on medications for diabetes, people with a history of eating disorders like anorexia and bulimia, and pregnant or breastfeeding women should not attempt intermittent fasting unless under the close supervision of a physician who can monitor them’’.
*This article is not intended to replace medical or dietary advice, diagnosis or treatment given by a qualified health professional. Instead, this article only provides information, not advice. For any medical enquiries, always consult your GP first*