It doesn’t matter if you lose weight fast or slow, according to new research

This changes everything

Losing weight quickly or slowly is no longer considered to be the biggest indicator of long-term weight loss. Image: Getty

Whether it’s dropping a dress size before a big event or taking things slow, the likelihood of regaining weight that’s been lost either way is higher than you think.

Among the most popularly believed myths in diet culture is that weight loss rapidly was just as quickly regained and that if you really wanted to do things the “right way”, slow and steady wins the race. 

But new research has revealed everything we thought we knew about fast weight loss and slow weight loss might be wrong. 

“The research shows that irrespective of how you lose the weight it is likely to be regained,” Dr Nick Fuller, a researcher at the University of Sydney and founder of Interval Weight Loss says.

In Australia, rapid weight loss is defined as losing over half a kilo a week for a number of weeks ongoing, while slow weight loss is defined as losing up to half a kilo per week for a number of weeks. 

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“The diet industry has made us believe for decades that we are failing on our diet attempts due to a lack of willpower – that we just don’t stick to the diet for long enough,” Fuller says, adding that research now shows that a person’s success in losing and maintaining weight loss long term has little to do with how hard we try, how easily we give up or how often we indulge in ‘cheat’ days and more to do with biology.  

“The real reason we fail on our diet attempts is due to our biology. Research shows it doesn’t matter what type of diet you follow – keto, low carb, high protein, vegan, meal replacements – because all diet approaches achieve similar long-term weight loss outcomes.” 

Looking at the issue from an evolutionary perspective, Fuller explains that our bodies are designed to protect us against weight loss and working hard to regain any weight that is lost. This happens through the metabolism slowing down, the body burning fewer calories during rest periods and appetite hormones adapting to crave more food. 

Losing weight slowly can help you maintain healthy habits like regular exercise. Image: Getty

“It’s an evolutionary problem which requires an evolutionary solution,” Fuller says, acknowledging that to date, there is no pill, shake, injection or fast can reprogram or override these functions overnight.   

That’s not to say that there aren’t pros and cons to losing weight in different ways, entirely though and that five kilos lost through meal replacement shakes in a month is equal to losing the same amount over three months through lifestyle, exercise and dietary changes. 

“Slow weight loss is shown to be better for preserving our metabolism or how many calories we burn at rest, increasing your odds of keeping the weight off long-term. Slow weight loss is also better for bone density because rapid weight loss results in twice as much bone loss and puts a person at increased risk of brittle bones or osteoporosis,” Fuller explains. 

Research also shows that interval weight loss, whereby a person undertakes four-week cycles of losing weight and sustaining weight loss can also be highly effective in the long term because it disrupts the body’s usual responses to weight loss and allows a person time to adapt to the changes gradually.

What’s more, rather than just a set of numbers on the scale or clothing tag, Fuller says that when it comes to weight, we need to look at it from a more holistic perspective and focus on health benefits instead of aesthetics alone. 

Slow weight loss is shown to be better when it comes to keeping weight off long-term. Image: Getty

“We need to be focusing on long-term outcomes and factors aside from weight, such as health and bone density. Just a small, but clinically meaningful weight loss that is sustained will result in improvements in health.” He adds, “Health is also more important than weight, as you can be healthy but overweight, so setting a target weight based on the healthy BMI ranges is not always necessary or realistic.” 

Research shows that losing and sustaining weight loss of 5 per cent of your body weight can significantly reduce your chances of developing heart disease or type 2 diabetes. The healthy habits often formed while trying to lose weight, like prioritising sleep, exercise and eating a balanced diet and developing a healthy relationship with your body throughout this period, are also the basis of improved and sustainable health. 

Given the physical and mental health challenges associated with weight, Fuller says that when it comes to finding the right course of action for you - slow or fast - the most important first step is ensuring your information and guidance come from a specialised source. 

“When attempting to lose weight and restore health, it is vital to seek help from qualified health-care professionals who have studied the science of obesity, not celebrities or social media sensations that are interested in nothing more than pushing their quick fix ‘fad’ diets onto their large followings,” he says.

Originally published as It doesn’t matter if you lose weight fast or slow, according to new research