Protein is exceptionally important! It is an essential macronutrient, critical for countless processes within the body. Protein is especially important for anyone concerned with muscle retention, growth and/or recovery.
Although whole foods are best, consuming protein in the form of protein powder can be useful at certain times, especially for those who exercise and train regularly. Supplementation of protein in the post-training period may assist optimisation of recovery and subsequent performance (1).
But with so many different options, how do you know which one to choose? This article includes: what to look for in a protein powder, different protein powder sources and whether protein powder is for you!
Protein is made up of building blocks called amino acids of which there are different categories:
Essential amino acids (EAA): amino acids that the body cannot synthesise itself and must be gained through the diet.
Non-essential amino acids: amino acids that the body can synthesise itself.
Conditionally essential amino acids: amino acids that the body can make but isn’t always able to make – it is dependent upon the status of the body and its priorities i.e. whether you are training hard, sick or undernourished.
Branched-chain amino acids (BCAA): a subcategory of EAA, specifically leucine, isoleucine and valine that are particularly important for initiating muscle protein synthesis.
Protein quality is a measure of a protein source’s ability to provide adequate quantities of the EAA required for protein synthesis (2). Protein quality may have an effect on short and long term adaptations to exercise (1). A complete protein source includes sufficient sources of all of the nine different EAA, whereas an incomplete protein source is lacking or low in EAA.
Plant proteins are incomplete protein sources because they lack or are low in specific amino acids and therefore may be lower in protein quality. Hence, the creation of blended plant proteins! For example, a pea/rice blend has a full EAA profile and is therefore a higher protein quality.
For those of you concerned with muscular retention/gains and the muscle protein synthesis process, the BCAA leucine is especially important. Leucine is necessary for initiating muscle protein synthesis – this is critical for both the adaptive and recovery processes following training sessions (3). Protein supplementation with a higher content of leucine, in combination with resistance training stimulates muscle protein synthesis to the greatest degree (4).
Animal based vs plant-based protein
Animal based protein powders are the most bioavailable source of amino acids and contain all EAA. Whey protein has the highest leucine source. For individuals who may be lactose intolerance (5), whey may not be suitable – there may be impaired absorption of protein as well as symptoms of digestive discomfort – a bloated stomach, cramps/pains, or feeling sick (6).
Additionally, individuals may wish to choose a plant based protein powder based on personal preferences – such as environmental and/or ethical opinions. Ultimately whether you choose animal or plant-based protein is down to your physiology and personal preference.
Include intolerance/sensitivity to eggs and/or dairy. Soy is also an allergen. Additionally added ingredients, such as bulkers, fillers and sweeteners may be a source of intolerances/sensitivity causing gastrointestinal discomfort and symptoms.
Protein powders often have a variety of ingredients added to them. Sugar based sweeteners include: honey, maple syrup, cane sugar, brown rice syrup, coconut sugar, molasses and agave. Consumption of high amounts of sugars can contribute to the production of harmful substances in the body (ROS), an imbalance of energy and are associated with detrimental effects on health (8,9,10).
Artificial sweeteners added include: sucralose, aspartame, saccharin; sugar alcohols: sorbital, malitol and erythritol. Artificial sweeteners are indicated to affect the gut microbiome, some are indicated to influence the insulin response and may be detrimental to health (8,9,10). “Natural” sweeteners commonly included are: stevia and monkfruit. There is less research on their impact currently available. Sugar alcohols are another added potential ingredient which may contribute to digestive upsets (39).
Protein powders frequently have thickening agents added (examples are guar gum/ xantham gum, dextrins, inulin) and emulsifiers (such as carrageenan, lecithins). Although small amounts of thickening agents and emulsifiers are indicated to be safe (11), there is growing research to indicate that they may impact gut and metabolic health (12).
Research on the impact of these types of added ingredients is still relatively new – if you are considering including these types of added ingredients, be aware of how much you are having of them and check how far down the ingredient list they are. Anything that’s stated at the beginning of the ingredient list, there will be more of and less is at the end. Additionally, unless the protein powder is unflavoured, then a flavouring will be included too, so watch out for that!
Different protein sources:
Pros: a complete protein that includes full range of amino acids; is absorbed and digested quickly; contains the highest proportion of BCAAs; contains highest content of leucine.
Cons: not advised for any autoimmune/allergen issue and or sensitive/intolerant to dairy as associated with digestive issues.
Pros: complete protein that includes full range of amino acids; more slowly absorbed than whey which may be beneficial for overnight periods.
Cons: not advised for any autoimmune/allergen issue and or sensitive/intolerant to dairy.
Pros: complete protein source; may produce similar gains in strength and lean body mass as whey (in combination with resistance training) (13).
Cons: soy protein is a common allergen so avoid if any autoimmune/allergen issue (13). Soy has received controversial attention regarding hormonal health, but research indicates that it is not harmful to male or female hormonal health (14,15).
Pros: good plant-based source of BCAA; rich in amino acid lysine; highly digestible; hypo-allergenic. Pea protein may be the superior plant protein due to its content of lysine which may contribute to the activation of the muscle synthesis signalling pathway (16). Some research indicates that pea protein supplementation performs equally well as whey protein supplementation for body composition, force production, performance and strength (17).
Cons: incomplete protein source – low in essential amino acid methionine (18).
Pros: hypo-allergenic and almost a complete protein source. A comparison of rice and whey protein supplementation in conjunction with resistance exercise shows them to both improve lean body mass, muscle mass, strength and power equally well (19)!
Cons: incomplete protein – low in amino acid lysine (19).
Pros: high in fiber, high source of omega-3 fats
Cons: incomplete protein – low in amino acid lysine; overall lowest protein content per average scoop of protein powder.
Blends – pea/rice blend:
The combination of two plant based proteins facilitates a robust amino acid profile whilst remaining plant based and/or avoiding risk of food intolerances/sensitives. To replicate the effects of whey protein, whilst keeping it hypoallergenic and plant based, add some leucine to the pea/rice blend.
Pros: complete protein sources which complement one another; hypoallergenic; both shown to perform equally well to whey for muscle mass, strength, body composition and performance (18)
Cons: slightly lower in protein that some other plant-based options.
Do you need protein powder?
Although protein powder isn’t an essential, meeting your protein requirements is. Sometimes it can be challenging to consume adequate protein depending on individual requirements, training volume, body size and daily life. As well as having greater protein requirements, athletes training multiple times a day have fewer opportunities to consume recovery meals and ensuring protein intake within a window following training may promote recovery and future performance (1).
Times when protein powder supplementation may be especially helpful:
Meal replacement: combining protein powder with some vegetables, a tasty fat source such as brazil nuts and blending with some water/plant based milk is a quick and easy way of getting a delicious and nutrient dense meal in. Think whole foods meets fast foods. There are plenty of other blender based meals using similar ingredients which can provide a variety of quick and tasty meals whilst ensuring that you hit your protein requirements – soups, waffles, pancakes, muffins, cookies, oatmeal, mug cakes etc.
Muscle gain: if you’re looking to gain muscle, then ensuring adequate protein and calories following your workout is key. A protein shake is a no fuss way to provide this. For example, a tasty shake post training session: pea/rice protein mix with added leucine, plant based milk and pre frozen mango and banana with some sprinkled coconut flakes for some crunch on the top.
Weight loss: upping your ratio of protein intake is a useful tool to retain lean muscle and starve off hunger. If you’re looking to go lower carb with your weight loss then think less fruit and go for the lower carb options (such as berries) and get some quality filling sources of fibre in there from some veg like courgette/spinach/cauliflower.
Recovery/athletic performance: ensuring overall calorie and macronutrient intakes are met is essential for optimising athletic recovery (3) and a protein shake is a simple, no fuss solution to ensure that you meet your recovery needs. Taking a protein shake post training ensures you can replenish the body with the adequate nutrients and calories it requires.
A post-workout protein shake may improve both recovery (20, 21) and future performance (22,23). Also, a protein shake in the post workout window may be particularly important for certain individuals – for example, individuals who compete at a high level within athletics, pro bodybuilders, very lean individuals, or those who are engaging in more than one exercise/activity session a day or longer sessions.
Low appetite: for anyone who finds it challenging to get in their calorie needs then a smoothie with protein powder can be a great way of easily getting in your energy requirements, whilst keeping it nutrient dense and including great whole food sources!
Meeting protein requirements is critical regardless of your goal: gaining muscle, losing weight, retaining muscle, improving strength and performance and enhancing recovery.
Protein powder may be a useful tool to meet your goals: whether it’s for convenience or you are training multiple times a day then protein powder can be a handy way to meet your calorie and macro requirements. Depending on the individual, taken in the post exercise window, may optimise the recovery and performance.
When choosing a protein powder consider protein quality, BCAA and leucine content and any added ingredients: the beauty of a making your own protein shake is that you get to choose what is in it! So choose a protein powder that suits you – what works for your body and personal preferences!