New Study: Intermittent Fasting Feels Easier Than Calorie Counting – Here's What That Means for Weight Loss

Could intermittent fasting be easier than counting calories when it comes to losing weight? New research from Adelaide University suggests it might be – at least for some people.

Both intermittent fasting and continuous calorie restriction were found to lead to roughly the same amount of weight loss, but those cutting calories every day reported having to make a greater conscious effort to limit exactly what they ate and avoid overeating. The fasters, on the other hand, didn’t report the same increase in dietary restraint.

So, does that mean fasting requires less willpower – and is potentially easier to stick to in the long term?

Researchers randomly assigned 209 adults with obesity – 57% of whom were women, with an average age of 58 – to one of three groups: intermittent fasting, continuous calorie restriction, or standard healthy-eating advice (also known as the 'standard care' group).

Those in the intermittent fasting group consumed 30% of their usual energy needs between 8am and 12pm on three non-consecutive days each week, followed by a 20-hour fast. On the other four days, they ate normally without restriction.

Meanwhile, the calorie-restriction group ate approximately 70% of their usual energy intake every day, while the other group simply received healthy eating advice at the beginning of the study.

After six months, those in the intermittent fasting group and the calorie-restricted group lost an average of 7kg, compared with around 2kg in the standard care group.

Both dieting groups also reported improvements in depression and general wellbeing. So far, so broadly similar.

But the researchers weren’t only interested in what happened on the scales. They also looked at the psychological side of dieting: how much participants thought about restricting food, how hungry they felt, their tendency to overeat and the effect each plan had on their mood, sleep and quality of life.

The researchers, whose findings were published in the journal Clinical Nutrition, measured something called 'dietary restraint' – which is basically the conscious effort involved in limiting what you eat. Think: calorie calculations, portion negotiations and the internal debate about whether you are genuinely hungry or simply fancy another roast potato.

The daily calorie-restriction group reported a greater increase in this kind of restraint. But they also reported bigger reductions in hunger and ‘disinhibition’ – the scientific term for being more likely to overeat in response to particular situations or emotions. This shift appeared to account for around 15% of the calorie-restriction group’s weight loss.

The intermittent-fasting group, meanwhile, lost a similar amount of weight without reporting the same increase in conscious restraint.

To put it simply: one group seemed to lose weight partly by getting better at stopping themselves from eating more. The other followed stricter rules on three days a week, but didn’t appear to spend the remaining days constantly policing their intake.

‘Intermittent fasting may help people achieve weight loss through ways that are less dependent on consciously restricting intake,’ said study author Professor Leonie Heilbronn.

For some people, ‘I’m eating less today’ may feel simpler than continually counting, tracking and negotiating every meal. Others will find a 20-hour fast completely miserable and would much rather eat a little less across the week.

The study didn’t establish which personality type is destined to thrive on intermittent fasting. Nor did it test every variation of fasting currently being promoted online. It examined one very particular plan in adults with obesity.

Intermittent fasting isn’t for everyone – anyone who is pregnant or breastfeeding, has a current or previous eating disorder, or takes diabetes medication should speak to a doctor or registered dietitian before attempting it.

This study showed intermittent fasting wasn’t actually any better for weight loss than eating fewer calories every day.

What it does suggest, however, is that fasting may allow some people to lose weight without feeling as though they are constantly monitoring and restricting every mouthful.