It's that time of the year when solutions for losing unwanted kilos are beckoning.
It might be an online program, a diet book, home-delivered portion controlled meals or meal replacement shakes.
But when it comes to sizing up how effective a plan might be there's no way of telling whether it works until you've parted with your money and given it a go.
No great loss if the only investment is $30 for a diet book, but an online program costing a few hundred dollars is a bigger gamble.
Then there's the problem of getting sucked into a series of dieting attempts that fail - this can set you up for a lifelong tussle with weight gain, says Professor Kylie Ball of Deakin University's Centre for Physical Activity and Nutrition Research.
"Repeated dieting is a strong predictor of weight gain throughout adult life and it can happen when people try diets that don't work in the long-term then regain the weight and repeat the cycle - this can lead to an unhealthy relationship with eating," she says.
But research into weight loss offers some clues about what works and an important feature of a good program is that it provides skills that teach how to maintain good eating habits for life - like preparing healthy meals, understanding portion control and being more physically active.
This is where meal replacement shakes and home delivered portion-controlled meals can fall short.
"Meal replacement shakes may lead to initial weight loss if they result in an overall energy deficit - meaning you burn up fewer kilojoules than you eat. But they don't focus on physical activity and don't teach you to how to feed yourself healthy meals," says Ball.
"Home delivered meals have the advantage of showing what a reasonable meal content and portion size for weight loss might be, but don't provide any skills for keeping weight off permanently.
"The long-term sustainability of these approaches is unknown - what happens once someone stops the meal replacement or meal delivery and returns to their normal way of eating without having learned any skills?"
What about online programs? They're promising, says Dr Melinda Hutchesson of the University of Newcastle's School of Health Sciences who's soon to begin a study of an online weight management program aimed at women aged 18 to 30.
"The advantage of the online approach is that it's easily accessible and a review of research into online programs by the University of Newcastle has shown they can be as effective as face to face counselling for weight loss.
"The problem is keeping people engaged with an online program -it's easy to ignore your computer," she says. "If you're choosing a program look at who has developed it - is it someone with qualifications like an Accredited Practising Dietitian or registered fitness professional?"
Signs that a weight loss approach is worth trying, says Ball, include:
- It focuses not just on diet but on increasing physical activity.
- It teaches techniques that help to change habits such as how to set achievable goals to stay motivated or how to track food intake and physical activity (via a diary or an app, for instance) to raise awareness of eating and exercise behaviour and what needs to change.
- It promotes gradual weight loss of around 0.5kg to 1kg a week - no program should promote a weekly weight loss of more than around 1kg.
- It's a plan you can incorporate into your lifestyle over the long haul - not just a few months.
Signs that a program could be a dud?
Advice to cut out entire food groups or claims of dramatic weight loss, says Ball.
And be wary of hefty price tags, she adds.
- Sydney Morning Herald
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