While many use meal replacement shakes as a weight loss tool, how effective are they in helping us to shed the kilos?

Losing weight can be really, really tough. So it’s no surprise that there’s big money to be made in weight loss aids, especially if they work.

One popular option is meal replacement shakes, which allow you to replace a regular meal with a shake (plenty of people would rather drink a chocolate shake for breakfast than eat a bowl of porridge).

The idea behind meal replacement shakes is to replace one or two meals a day to help reduce the chances of over-eating, says Associate Professor Tim Crowe, an accredited practising dietitian and nutrition researcher at Deakin University.

They can be a good option for people who are time poor or lack skills and interest in cooking, he says.

“An advantage of using shakes to help with weight loss is they are very easy to use.”

While shakes provide reasonable nutrition, he says they are not designed to replace your whole diet.

“To lose weight you do need to eat sensibly around them and your other meals still have to be portion controlled.”

“They are reasonably high in protein and lead to a feeling of fullness. But as part of a calorie reducing diet you will be hungry. You can’t hide that.”

Crowe says there is evidence that meal replacement shakes can help you lose weight if you use them as directed.

“Overall the evidence is reasonably positive that they help with weight loss for up to a year. This is as sustainable as any other method of weight loss, but most people do regain weight.”

However, people tend to do better with weight loss if they get support from a dietitian, he says.

You’ll find meal replacements in pharmacies and health food stores. Many come as powders that you make into shakes, but some come in the form of soups or bars. Crowe says there are regulations around what can be called a meal replacement – for instance, they must provide adequate amounts of 16 vitamins and minerals.

Crowe says you should ensure you know what you’re buying as other protein and energy bars are likely to be high in sugar and kilojoules and not suitable if you’re trying to lose weight.

Problems with shakes

But this doesn’t mean we should all start replacing meals with shakes.

For starters, while meal replacement shakes might be convenient, replacing meals isn’t going to help you get a handle on learning how to eat in a healthy way so that you can maintain any weight loss for the long-term.

They also don’t contain everything you need when it comes to a healthy diet. Crowe says: “they don’t contain enough fibre and they lack phytonutrients, which are beneficial nutrients from fruit and vegetables.”

As well, meal replacements miss the mark when it comes to the pleasure of eating. This is not just about the wonderful variety of tastes, smells and textures that you experience when eating food; it’s also about the social aspects of eating. Humans have always enjoyed sitting down together to eat real food.

“Shakes don’t address the social aspect of eating and people using them will have a hard time eating out,” Crowe says. “You can’t eat like that forever. Taste fatigue can be quite common.”

Medically supervised weight loss

Dr Priya Sumithran is an endocrinologist and researcher from the University of Melbourne Department of Medicine at Austin Health whose research focuses on obesity.

She says many weight loss clinics use meal replacements as part of a supervised very-low-energy diet (VLED) for people with obesity. Only shakes formulated for adequate nutrition are suitable for use as part of a VLED.

“Using meal replacements as part of a very-low-energy diet should only be done under medical supervision,” she says.

This helps ensure the right product is being used in the right way, that people can have their health conditions monitored and they have someone to discuss questions and concerns with.

By Dr Jocelyn Lowinger. This article was originally published on ABC’s The Pulse on the 15 June 2015.