How do meal replacements work for weight loss?

Losing weight is especially difficult in today’s fast paced world. Bouncing from one destination to the next can make it difficult to plan quick, healthy, low calorie meals. As a result so many of us fall into the trap of eating convenient processed foods. Enter the meal replacement shake, a powdered drink formulated specifically to help you lose weight whilst still covering your nutritional needs. 

Of course, weight loss is all about expending more calories than you consume, so in order to lose weight you need to reduce your calorie intake. Meal replacement shakes tend to be low in calories, ranging anywhere from 100 to around 400 calories - in many cases, these shakes aren’t really nutritionally or calorically dense enough to be a true meal.

In general, whole foods as part of a balanced diet are always the most important: especially as they contain fibre, which is often lost in a meal replacement shake. However, they do have their place, and can be a useful tool - as long as you’re not reliant on them. 

The perks of meal replacements is that they’re an easy and convenient way of covering the body’s nutrient requirements in a smaller amount of calories when you’re in a rush or on the go. They’re usually pretty high in protein, with fewer carbohydrates and supplemented with vitamins and minerals. But how many meals can you replace with liquid? Do meal replacement diets work for weight loss? And are they actually good for you?

How can meal replacements help with weight loss?

A calorie deficit, no matter how it’s achieved, will cause weight loss - you could eat a diet of Mars Bars and lose weight, assuming you’re taking in less calories. Of course that doesn’t mean it’s healthy!

At the most basic level, the small amount of calories in a meal replacement shake in place of a full calorie meal will help you achieve a calorie deficit (alongside a good diet and exercise). Picking up a ready-made, portable meal replacement shake also means that you’re less likely to opt for a processed option, full of sugar, artificial ingredients and saturated fats. However, it misses out fibre, and can sometimes not be calorically dense enough to see you through the day.

When used properly though, meal replacement shakes can help you feel fuller for longer. Given that they’re high in protein, the most satiating macronutrient, they’re likely to prevent you overeating later in the day. High protein diets are also associated with benefits like increased lean body mass, less body and belly fat, and better weight maintenance. However, not all meal replacements have an adequate amount of protein - we’d recommend choosing one with at least 20 grams of protein, like our WHOLE Plant Based Nutritional Shake.

They also help control your hunger through their low glycemic index, which measures how quickly food causes blood sugar to rise. Foods with a low glycemic index release sugar into the blood in a more slow and sustained way, helping you feel fuller for longer. 

Despite their low glycemic index, meal replacement shakes are nutrient-dense. Cutting back on calories can often lead to nutrient deficiencies as you’re eating less food so naturally consuming less vitamins and minerals, which is where consuming a meal replacement shake fortified with nutrients can help bridge those nutrient gaps. WHOLE packs in a whopping 22 essential vitamins and minerals from plant based sources, as well as essential fats including Omegas 3, 6 and 9.

Should I replace all my meals to lose weight?

No matter what your goals are, whether you’re looking to lose, gain or maintain weight, shakes cannot replace a healthy diet full of whole foods. 

Although most meal replacement shakes are fortified with vitamins and minerals, whole foods contain vital antioxidants, fibre, plant compounds and enzymes, which can’t just be shoved into a bottle. These essential phytonutrients have been found to combat inflammation, as research has found that people who eat more foods with antioxidants and phytochemicals have less chance of developing chronic diseases. 

Similarly, proteases, lipases and amylases, digestive enzymes which help us break down food molecules, are found in whole foods to help you absorb nutrients, making the most of your calories in a way that a meal replacement shake cannot. Many meal replacement shakes don’t contain prebiotic fibre and probiotic bacteria, which have been found to improve the bacteria living in your digestive tract, positively affecting your nutrient absorption, immune function, inflammation and physical performance. Our plant-based nutritional shake WHOLE does contain a digestive health blend, including 5 billion probiotics per scoop along with digestive enzymes to support healthy digestion and absorption.

Another reason why you shouldn’t replace all your meals with shakes is because studies have found that hunger hormones like ghrelin are affected differently in solid versus liquid food, concluding that people who chew their food feel fuller after chewing, even with the same amount of nutrients and calories. Meal replacement shakes are therefore not a dietary equivalent to food, and shouldn’t be consumed for all 3 meals a day.

How do I ensure I’m getting a balanced diet using meal replacements? 

Using a meal replacement can help you with a balanced diet itself, as it can help bridge any nutrient gaps in your diet. However, to ensure you’re getting all the other antioxidants, phytochemicals and digestive enzymes that meal replacements often lack, make sure you also have plenty of fruits and veggies throughout the day.

To make a low calorie shake like WHOLE into a full, nutritious meal, you can add some carbs like oats for a satiating, nourishing breakfast, topping it off with some fresh berries and bananas for the anti-oxidants and dietary fibre.

What are the risks of using meal replacements to lose weight?

Like any kind of diet where the number of calories consumed is drastically reduced, using meal replacement shakes too often can slow your metabolism. Your body gets used to surviving on fewer calories, meaning that when you start to eat food again, you’re more susceptible to weight gain.

Very low calorie diets can also spark symptoms of dizziness, headache, fatigue, cramps and digestion problems. Most of the risks with meal replacements come from using them too often and not eating enough whole foods to provide a better balance of nutrients and to encourage sustained, long-term weight loss as opposed to crash dieting. 

To avoid encountering any health issues with meal replacements, the key is to ensure you only use low calorie shakes as a snack or a nutrient base, and eat real whole foods alongside them. You’re much more likely to sustain your weight loss and lose fat in a healthy way if you don’t try and replace three meals with liquid. Not only is it better for your health, but also for your soul - after all, food is a source of enjoyment, and you deserve to enjoy your meals!