At first glance, meal replacement shakes and protein shakes are very similar. They’re both powdered, and the process of making them is largely the same: open packet, scoop powder into the appropriate vessel, add liquid, shake or blend, and then drink.
They both contain levels of protein, carbohydrates, and fats. However, that’s just on the surface. In reality, these two are designed to help you achieve different things, have different compositions, and where one might be suitable for you at one stage of your life, another might be suitable later down the line if your goals change. Meal replacement shakes, for example, are traditionally used to help with weight management whilst protein powders are used to enhance athletic performance and muscle gains.
This guide looks at the functions of each product, the goals they can help you and achieve, and what makes them different. Let’s start with protein shakes.
What is a protein shake?
People drink protein shakes for all sorts of reasons including muscle gain and toning, weight loss, and muscle recovery. They are a dietary supplement containing amino acids (the building blocks of protein), they have a plethora of functions surrounding exercise and musculature, and they’re generally used to supplement an athletic lifestyle. In short, protein shakes are designed to help you achieve your fitness goals, whatever they might be.
Combining resistance training with protein shakes can enhance performance and encourage faster recovery (Cermak et al., 2012). This combination is also great for building muscle, as both increasing protein intake and increasing resistance training stimulates a process called muscle protein synthesis. The elevated levels of amino acids in protein shakes is also thought to encourage a higher rate of muscle protein synthesis (Davies, Carson and Jakeman, 2018).
Whilst protein shakes can help you lose weight (if that’s your goal!), studies have also shown that they can help to retain muscle mass if you’re actively trying to lose weight (Hector et al., 2015).
What is a meal replacement shake?
Meal replacements are intended to replace a meal. They are higher in calories than a protein shake, but often not as high as a complete meal, which makes them popular for weight loss and management. They are intended to substitute one or two meals a day, and are usually fortified with vitamins and minerals in order to replicate the nutrient profile of a complete meal (Hamdy and Zwiefelhofer, 2010).
They offer more fibre and carbohydrate than protein shakes, and whilst they do provide protein, it is usually in lower quantities than you find in a protein shake. They also tend to have a more variable protein content than protein shakes. Those designed for weight loss, for example, may have a higher protein content than those designed for nutrition or general wellbeing.
Many meal replacement shakes are designed not just to replace a meal, but to encourage and aid in nutritional wellbeing for people who might not be able to get the same nutrients and calories out of a whole foods diet, such as people with certain gastrointestinal conditions, the elderly, or children with metabolic conditions. When these supplemental nutrition drinks are used, they are often in addition to meals, instead of replacing them entirely. They have also been shown to be very effective in weight management for people with diabetes (Yip et al., 2001).
What is the difference between protein shakes and meal replacement shakes?
The biggest difference between protein shakes and meal replacement shakes is in their composition. Because they are created to fulfil different needs, their contents needs to reflect the overall goal:
- Proteins: It might not surprise you to know that protein shakes generally have higher amounts of proteins than meal replacement shakes, although some do contain higher amounts of protein to help you feel fuller for longer and keep you going until your next meal.
- Fats: Protein shakes usually contain fewer than 3g of fat, but the fat content of meal replacement powders tends to vary, again depending on the intended use.
- Carbohydrates: Where protein shakes typically have less than 5g of carbohydrate per serving, most meal replacement shakes tend to contain higher levels of carbohydrate and dietary fibre to mimic the nutritional profile of a complete meal.
- Vitamins and Minerals: As protein shakes are designed as a supplement for an active lifestyle with a healthy, balanced diet, it’s not usually necessary for them to contain lots of vitamins and minerals. This couldn’t be further away from a meal replacement shake where a full nutrient profile is important to ensure that your body is not lacking key nutrients from replacing a meal.
Which should I use?
Well, that depends on what you’re trying to achieve right now. If you need a product to supplement and help to fuel high intensity workouts, then you’ll need a protein shake to help you build, tone, and repair muscle. They can be used before or after a workout on and even on rest days. Choosing a protein shake which has high levels of protein, a strong amino acid profile and easily digestible protein is key to ensuring that you get the most out of your shake. PERFORM is a protein powder which contains 25g of plant-based protein per serving, along with an enzyme blend to aid digestion and turmeric for faster recovery.
Meal replacement shakes are not designed to replace a healthy, whole foods diet. Whilst they can be a flexible, convenient option, they shouldn’t not be used full time. Remember, whole foods contain myriad compounds to aid in digestion and keep you healthy that just cannot be replicated by a shake! (López Barrón et al., 2011)
If you’re looking for a nutritional supplement or a product which will help you to manage your weight or give you a boost of calories, then a meal replacement shake is what you’re looking for. However, there are varieties of shake out there, such as Vivo Life’s WHOLE, which are designed as a nutritional drink rather than a direct meal replacement. This gives you the option to add new flavours and textures to the shake itself, to manage your own nutrient profile and calorie content, and to create a shake which can become part of a meal, should you choose to do so!
Cermak, N.M., Res, P.T., de Groot, L.C., Saris, W.H. and van Loon, L.J. (2012). Protein supplementation augments the adaptive response of skeletal muscle to resistance-type exercise training: a meta-analysis. The American Journal of Clinical Nutrition, 96(6), pp.1454–1464. doi:10.3945/ajcn.112.037556.
Davies, R., Carson, B. and Jakeman, P. (2018). The Effect of Whey Protein Supplementation on the Temporal Recovery of Muscle Function Following Resistance Training: A Systematic Review and Meta-Analysis. Nutrients, 10(2), p.221. doi:10.3390/nu10020221.
Hector, A.J., Marcotte, G.R., Churchward-Venne, T.A., Murphy, C.H., Breen, L., von Allmen, M., Baker, S.K. and Phillips, S.M. (2015). Whey protein supplementation preserves postprandial myofibrillar protein synthesis during short-term energy restriction in overweight and obese adults. The Journal of nutrition, [online] 145(2), pp.246–52. doi:10.3945/jn.114.200832.
López Barrón, G., Bacardí Gascón, M., De Lira García, C. and Jiménez Cruz, A. (2011). [Meal replacement efficacy on long-term weight loss: a systematic review]. Nutricion Hospitalaria, [online] 26(6), pp.1260–1265. doi:10.1590/S0212-16112011000600011.
Yip, I., Go, V.L.W., DeShields, S., Saltsman, P., Bellman, M., Thames, G., Murray, S., Wang, H.-J., Elashoff, R. and Heber, D. (2001). Liquid Meal Replacements and Glycemic Control in Obese Type 2 Diabetes Patients. Obesity Research, 9(S11), pp.341S347S. doi:10.1038/oby.2001.140.