A nutritionist reveals everything you need to know about intermittent fasting
Intermittent fasting is polarising. Some people shout its benefits from the rooftops, saying it helped them lose weight and increased their energy, while others denounce it as yet another fad diet.
In order to get our facts straight, we spoke to Jaime Rose Chambers, accredited practising dietician and nutritionist, as well as the author of ‘16:8, Intermittent Fasting’.
What is intermittent fasting?
Unlike a diet, fasting doesn’t restrict the types of food you eat, just when you’re eating. “Intermittent fasting is referred to as a health strategy because it’s not a diet, it’s a pattern of eating,” says Jaime. “You eat normally, but just within a specified time period of the day and the remainder of the day, you take in no calories or kilojoules.”
Are there different kinds of intermittent fasting?
You may have heard of intermittent fasting without even realising. The 5:2 diet was quite a popular term previously, but Jaime says the “the most researched and most popular method is the 16:8.”
“This is where you fast for 16 hours of the day and eat within an eight hour period of the day,'' she explains. “The other, 5:2, is where on two days of the week you eat a quarter of your daily energy needs (500 calories for women and 600 calories for men) and the other five days you eat normally.”
Does intermittent fasting affect your hormones?
While you should always see your health practitioner before making any lifestyle changes, Jaime says the jury is still out on whether intermittent fasting impacts the reproductive hormones.
“Anecdotally, most women have reported to me that fasting has helped to regulate their cycles but some feel that it did the opposite,” she says. “Women tend to be more sensitive to changing their energy intake, which may impact their hormones, so it’s important to ease into it slowly if you’re concerned.”
Does intermittent fasting help you lose weight?
Those who praise intermittent fasting usually do so because it helped them slim down. Jaime agrees it can be quite a good weight loss strategy, “because it limits the hours of the day you eat, which can trim out some excess calories.”
“Plus, it extends the time you spend in a ‘fasting mode’ overnight, which is when we begin using our fat stores for fuel, creating a fat loss,” she says. “In saying this, it isn’t a magic pill and it isn’t necessarily suited to everyone.”
Does intermittent fasting slow down your metabolism?
By mindfully putting your body into fasting mode, some people are often concerned it will mess with their metabolism.
But Jaime says that according to the studies done so far, this isn’t the case. “In fact, it may do the opposite because it can help to retain lean muscle which boosts resting metabolism.”
What are the benefits of intermittent fasting?
We’ve talked about weight loss, but there’s actually a whole host of benefits that can come from intermittent fasting.
“It can reduce the risk of most major chronic diseases such as type 2 diabetes, heart disease and possibly some cancers as well as neurodegenerative diseases like Alzheimer’s and Parkinson’s disease,” says Jaime. “Fasting may also help reduce inflammation, improve gut health, cognition, memory and depression.”
What are the drawbacks of intermittent fasting?
If you’re used to eating whenever you want, the transition to intermittent fasting can be tough. “Some people report that while they’re fasting, particularly initially, that they may experience headaches, lightheadedness, low energy and difficulty concentrating,” says Jaime.
How can you ease headaches when intermittent fasting?
If you do experience headaches from intermittent fasting, Jaime says it’s commonly “due to cutting out that morning coffee, so it’s ok to have a black tea or coffee if you miss the caffeine.”
“It’s also really important to keep fluids up and drink plenty of water to make sure you’re not dehydrated. Headaches may also be due to low blood sugar levels and although it’s uncomfortable, it usually disappears after a few weeks of fasting,” she says.
Can you take supplements while fasting?
Most of us wouldn’t think twice about it, but you should definitely check the labels on your supplement bottles if you plan on fasting.
“To stay in a ‘fasting mode’ you need to avoid anything that will trigger an insulin response so any supplements that contain carbohydrates or sugars, fats or proteins such as protein powders need to be avoided,” says Jaime. “Many vitamin and mineral supplements also need to be taken with food for either better absorption or to prevent it from upsetting your stomach, so it’s best to check the supplement instructions before taking whilst fasting.”
Is there anything you can eat or drink during the fasting period?
Don’t worry, it’s not completely cold turkey and provisions are allowed during the fasting period (phew).
“When you’re fasting, you can have drinks that have no calories so water, unflavoured sparkling water, unsweetened herbal tea and black tea and coffee,” says Jaime.
Do I have to fast on the weekends too?
Asking for a friend…
“It is really up to you as to whether you fast on weekends too, depending on what your goals are and what your lifestyle is like,” says Jaime. “I generally suggest that you don’t fast at least one day a week, just to have a break from it and allow for some flexibility over the weekend.”
What kind of food should you be eating once you break your fast?
If you’re wondering if you can binge on burgers because you were ‘good’ for a few hours, that’s not really the idea...
“Once you break your fast, you really should just continue to eat your ‘normal’ diet following general nutritional guidelines which are to eat mostly plant foods and some animal foods (if you’re not vegan) and minimally processed foods – the Mediterranean diet is a good guide, ” says Jaime.
Can you work out while fasting?
Some people find they don’t have much energy when fasting, but you most certainly can continue to work out. Jaime says some people find they have a greatly improved stamina, but if you’re struggling it’s best to “time your workouts so it’s within an eating period.”
Are there any people who should stay away from intermittent fasting?
This type of eating pattern isn’t for everyone and Jaime also says “it’s important for any vulnerable population to avoid fasting, such as anyone with a history of eating disorders, pregnant or breastfeeding, under 18 or the elderly.”
As always, check with your healthcare provider before making any lifestyle changes.
What are your tips for those who want to start intermittent fasting?
If you’re keen to give it a go, Jaime says its best to start slowly and build on it over time.
“For example, start with a 12 hour fast overnight, say from 7pm to 7am, then work your way up to 16 hours of fasting. It’s important to plan your time too so it works in around sleep, social arrangements, work and exercise. “
Have you tried intermittent fasting?