Meal replacement products are certainly all the rage in the weight loss industry at the moment, with new products emerging on a regular basis into what has become a very crowded marketplace. So what exactly are these products, do they work, and are they a viable alternative to just eating less food but choosing healthier options? Read on to have all these questions answered.
What are meal replacements?
Meal replacement products are designed to replace one or two of the main meals each day, with the remaining meals and snacks eaten along sensible dietary guidelines. Importantly, meal replacement products are not designed as a total diet replacement. Meal replacements come in a variety of forms with shakes, bars, biscuits and soups the most popular options.
To be classified as a meal replacement product, Food Standards Australia New Zealand specify formulas need to contain 25% of the recommended dietary intake (RDI) of 16 prescribed vitamins and minerals. They also need to contain adequate protein. The products are usually very low in fat, only contain a small amount of carbohydrate (the equivalent of a piece of fruit or a slice of bread) and often have added fibre. Products sometimes come with extensive educational material and recipes to educate people about healthy eating and positive lifestyle habits.
Do meal replacements work?
Despite some companies dressing up their meal replacement products in all sorts of pseudo-science for how they work (sometimes with a liberal dose of celebrity endorsement), there are no secrets or magical weight-loss science behind them. Considering each meal replacement contains well under 850 kJ (200 Calories), these products ‘work’ by reducing the portion size of a meal while also removing the likelihood of overeating at meals.
By sticking to a meal replacement plan, a person is simply following a very-low-kilojoule diet that is around 4000 to 5000 kJ per day (around 1000 Calories) which will result in weight loss for any adult.
When following a meal replacement plan, scientific studies show that weight loss of around 9 to 10% loss of body weight and significant decreases in abdominal fat can be achieved after six months of following this approach.
Over a period of 1 year or longer, not all of this initial weight loss is sustained by most people, but on average 6 to 8% of body weight can be lost. This amount of longer-term weight loss compares well with other types of dieting approaches. Importantly, the weight lost is usually associated with an improvement in weight-related disease risk factors such as high blood pressure, cholesterol and blood sugar.
It is usually the dramatic initial weight loss seen when someone starts a meal replacement program that is an effective ‘word of mouth’ advertising program for meal replacements, yet longer-term, not all of this weight loss is sustained so the hype is far different from the reality. When combined with counselling by a dietitian or as part of a lifestyle and diet education program with ongoing personal support, meal replacement products may be more effective.
The downside of meal replacements
While meal replacements are considered a very safe and reasonably effective way to lose weight, they do have some disadvantages.On their own, they don’t teach you how to choose a healthy diet from all the whole foods available
- They don’t contain all the micronutrients nor have all the other health benefits of eating whole foods
- The initial dramatic weight loss is rarely sustained
- They remove the social side of eating with friends and family, especially for meals eaten outside of the home
- They can be expensive.
What you need to know
For people who have not achieved success with other approaches, meal replacements can be considered an option. Meal replacement products though are not a vastly superior option to more traditional diets that focus on healthy eating guidelines combined with reducing the serving size of food and the amount of foods eaten that are high in fat. Importantly, such products do little to educate on healthy eating and controlling portion sizes when ‘real’ food starts to be eaten again.
While meal replacement products can meet the nutritional needs of most people, they still miss out on containing the huge variety of other nutrients normally found in food that can have a role to play in long-term health.