A meal replacement drink is intended as a substitute to a solid food meal.
The idea is to consume a shake with restricted calories as a convenient and effective way to lose weight. Meal replacement shakes have been used in the past to replace all meals throughout the day, however partial meal replacement is more common these days. Replacing one or two meals a day has become more popular to help manage / lose weight. This can be suitable for a short period of time but not recommended for an extended period as an approach to healthy eating is always favorable.
Metabolism and weight loss
To understand weight loss we must first understand how our metabolism works. Metabolism is the process by which your body converts what you eat and drink into energy. During this complex process, calories in food and beverages are combined with oxygen to release the energy your body needs to keep our human engines running.
Even when you're at rest, your body needs energy for all its "hidden" functions, such as breathing, circulating blood, adjusting hormone levels, and growing and repairing cells. The number of calories your body uses to carry out these basic functions is known as your basal metabolic rate - what you might call metabolism.
Typically people would assume that less food = less energy which = greater weight loss. Although somewhat true, starving our bodies of food by skipping meals in an effort to lose weight in fact slows our metabolism down and puts our body into an inbuilt survival mode where it begins to preserve energy and retain fat – not knowing when or where its next energy source is coming from (even if the next meal is only a few hours away). As a result weight loss can stall or become increasingly difficult.
An additional downside are our hunger cues. Drastically reducing calorie intake through skipping meals will increase the urge to snack and reach for something that is probably not as healthy as the meal that was skipped in the first place. The takeaway is that unless you have monk levels of self control or are as sedentary as a sloth we recommend to avoid skipping meals.
Do meal replacements help with weight loss?
The subject of meal replacements is touchy in the nutritional world. Dietitians and nutritionists will never recommend removing a meal altogether rather these could be replaced with a lower calorie / healthier alternative. The overall key to effective weight loss is to reduce our overall daily calorie (energy) intake while avoiding long periods of little to no food consumption. This is where meal replacements come in.
Lining the isles of any health section in your supermarket are a range of meal replacement shake options that come in either sachets or tubs of powder to be mixed with water to substitute for a meal. These products often contain a very low-calorie density and are low in sugars which is seen as desirable for weight loss goals but provides very little upside in terms of nutritional output – with many not being much better for you than flavoured dust.
This is where the effectiveness of smoothies comes into play. Gram for gram a smoothie a much healthier alternative than off the shelf purchased weight loss or meal replacement products. The flexibility of a smoothie allows the nutritional profile to be tweaked specifically to a person’s body composition goals and the convenience allows it to be quickly prepared and consumed on the go between meals - exactly when needed. Below is an example of a nutritionally complete smoothie that could be consumed between meals to keep the body energized and full whist low in calories to assist with weight loss. We have compared this to several products we have found in the meal replacement space.
Table 1 shows the comparison of nutrition content of popular meal replacements with a balanced smoothie:
When compared to a basic but balanced home-made smoothie the table shows how more calories can be consumed in conjunction with ingredients that promote a balanced diet and weight management. Interestingly the cost differences are marginal with a minimal amount more effort needed.
What should I look for in a meal replacement?
With 30 grams of protein (one generic serve of Go Good protein powder) the smoothie contains more than all three meal replacement options above. Protein is important to help with muscle repair as well as controlling your hunger hormone ghrelin to keep you feeling satiated between meals. Consuming a high amount of protein is key to the effectiveness of meal replacements.
Fiber is an important nutrient that keeps you feeling full and satiated due to fiber-rich foods taking longer to digest. fresh or frozen it is easy to include dense sources of fiber from fruit and vegetables into a smoothie as well as the added upside of the many vitamins and minerals found in these healthy foods.
Carbohydrates are an important aspect in charging our bodies energy stores to complete tasks and refuel after exercise avoiding fatigue. Too little carbohydrates can result in feeling tired, lack of concentration, and bloating or digestion issues related to a lack of fiber found in many carb-dense foods.
Additives & Fillers
It’s important to remember that the ready made, store purchased meal replacement shakes contain an extensive list of ingredients (22 was the highest we tested) including a range of additives, fillers, and chemicals – some that we even struggled to pronounce! Even when they are fortified with vitamins and minerals, these are usually synthetic and of lower quality than those found in natural foods.
Go Good protein powder on the other hand is a natural supplement consisting of protein derived from either animal or plant sources, real organic and natural flavor, as well as a natural sweetener. This protein supplement in conjunction with whole food sources makes for a great meal that promotes health and supports weight management.
Price is another factor in choosing to consume meal replacement shakes. These shakes can get expensive for a single serve of essentially a powder to be mixed with water. Smoothies however are the same price if not cheaper than some brands and provide much more complete and nourishing nutritional profile. Smoothies also offer an aspect of diversity in terms of what you can include in the meal opposed to the standard vanilla or chocolate meal replacement shake which neglects the ability to adapt the meal to personal needs, requirements, and preferences.
Meal replacement weight loss smoothie
A smoothie can be classed as a meal in itself as it has the ability to include a wide range of essential nutrients from whole foods sources.
Smoothies make a great meal substitution but not all smoothies are going to be ideal for reaching your weight loss goals. A healthy ‘meal replacement’ smoothie needs clean, lean protein to help you burn fat, detoxify your system, and create steady, sustained energy so that you can go longer between meals.
A few things to keep in mind when blending up your smoothie are as follows:
- Protein is the most satiating macronutrient therefore consuming the right amount at each meal is key to controlling hunger levels and maintaining a healthy body weight. It is recommended to include 30 grams of protein in your smoothie. The most effective and efficient way to do so is with a protein powder as they are low in sugar, sweeteners, calories and rich in high-quality protein that will help build metabolism-boosting lean muscle mass.
- Consuming whole-foods such as fruits, vegetables, and whole-grains which have a low GI (glycemic index) promotes healthy blood sugar levels due to slower digestion. Fruits and vegetables are also often high in fiber and nutrients while remaining low in calories. Whole-grains on the other hand can be more calorie dense so it is important to control how much you are including in your smoothie. We recommend oats to include as a filling, whole-grain kick.
- Healthy fat is another key macro nutrient in any meal as they slow digestion to maintain satisfaction, however you can quickly stack up the calories if not consumed in moderation. High fat foods often used in smoothies such as peanut butter, coconut yogurt, hemp seeds or chia seeds should be minimized. We suggest including only a teaspoon of one of these fat sources to ensure you are still getting all the benefits from these foods while controlling the calorie density of the smoothie.
Overall, meal replacement shakes may be a convenient way to take the thinking out of consuming a low-calorie meal. However, smoothies are a much better alternative as they provide the opportunity to pack your meal full of real nutrients to help keep you feeling full and satisfied. Learning how to prepare meals that are nutritious is a skill that will help you make life long and sustainable changes for your health and weight loss goals.
Take away points
- Don’t skip meals. Keep your metabolism firing, energy levels consistent and hunger cravings at bay by consuming your daily food intake evenly throughout the day.
- Meal replacement shakes are marketed as weight loss alternatives to solid food meals, however can lack nutrients found in whole foods and include a lot of unnecessary additives.
- Smoothies are a better option for a liquid meal to promote weight loss as you can include whole foods which contain a broad spectrum of healthy nutrients – with a good quality protein powder.
- Controlling the calorie content of your smoothie is key. Therefore, including plenty of protein, veg and some fruit will help you feel and stay full. Additionally, minimizing calorie dense high-fat foods will ensure the caloric density is controlled.