Warning: This story talks about eating disorders, disordered eating and restrictive eating practices.
From the 5:2 diet to the 16:8 method, intermittent fasting is growing in popularity.
The health trend involves cycling between periods of unrestricted eating and periods of restricted eating — with the restricted periods lasting for certain hours of the day or certain days of the week, depending on which plan you’re following.
While early research suggests fasting diets have some benefits, experts say they’re not for everyone — and readers should consult their health professional if they’re considering jumping aboard the fasting bandwagon.
So is it likely to be right for you, or should you steer clear?
The benefits, from easing inflammation to improved life span
The research into the effectiveness of fasting diets is in the early days. Some of the studies have primarily been conducted on animals, and researchers note there are still some concerns around the safety and feasibility of fasting diets.
But early research suggests fasting can help relieve health issues — from inflammation to arthritic pain to asthma, and promote positive changes associated with longevity and life span.
Fasting diets can also help with weight loss and improving associated biochemical markers — from hypertension, to blood glucose levels and cholesterol levels, says Dr Anika Rouf, an accredited practising dietitian and spokesperson for Dietitians Australia.
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But it’s not for everyone — these groups should avoid it
While fasting has become more popular in recent years, Dr Rouf says: “Generally we as dietitians would not recommend it, unless it’s something the individual really wants to do and we think it might be good fit for them.”
People with a history of disordered eating
For starters, anyone with a current eating disorder or a history of disordered eating should not embark on an intermittent fasting diet, says Dr Rouf.
Chris Fowler, of The Butterfly Foundation, says the organisation “does not endorse fasting diets that promote restricted eating behaviours such as the 5:2 diet or 16:8 diet” in general — because, he says, it is still a form of dieting. And dieting is one of the most significant risk factors for the development of disordered eating and eating disorders.
The organisation’s helpline has received calls from Australians saying, “I started off on these certain diets and I found myself reducing and restricting more,” he says, adding that fasting-style diets can be “a bit of a slippery slope” for some.
“It might begin in the realm of wanting to be healthy, but then it can spiral,” he adds.
“Fasting diets condition a mindset that there is a ‘right’ and ‘wrong’ way to consume food. Fasting diets encourage unhealthy practices around food and eating, often to lose weight and alter a person’s physical appearance.”
Another group who may be more at risk of developing an eating disorder: those with a family history of such conditions.
“We know there can be a genetic link to eating disorders — not to say that everyone who has a family member with a history of that will develop an eating disorder … but it does certainly put someone at risk,” Mr Fowler says.
Pregnant women, young people, athletes and those with certain medical conditions
“Children who are in the growing stages and teenagers — they should not be doing intermittent fasting,” says Dr Rouf.
Nor should anyone who’s very active, such as athletes, she adds.
Intermittent fasting is not appropriate for women who are pregnant, lactating or planning a pregnancy, says Dr Leonie Heilbronn, an associate professor in obesity and metabolism at the University of Adelaide who has researched intermittent fasting.
And if you have a medical condition “it is best to talk with your doctor before undertaking intermittent fasting”, adds Dr Heilbronn.
“This is particularly important if you have diabetes or take medications that may cause hypoglycaemia.”
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Beware these two stumbling blocks
If you’re thinking of trying fasting, it’s worth keeping in mind two common stumbling blocks.
Unsplash: Louis Hansel
Firstly, diet quality is critical to the success of intermittent fasting diets, says Dr Mark Larance, a senior lecturer in the University of Sydney’s science faculty, whose research has suggested intermittent fasting can change liver enzymes and help prevent liver disease.
“It’s important to maintain balanced healthy food choices and not think you can eat a poor diet (such as a high-fat and high-sugar diet) just because you’re intermittently fasting,” he says.
Dr Rouf says that similarly, those trying fasting should beware of the temptation to overeat during their ‘permitted period’ — for example, bingeing in the last few hours or minutes before their fast begins.
“This causes people to have this all-or-nothing approach — this sort of black-and-white approach around food and when they’re allowed to eat, that can be quite detrimental.”
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This content was originally published here.