How much protein should I be taking, and why?

We’ve all been there, you’ve bought your first bag of protein and you’re ready to get started. You’ve been taking the recommended amount on the packet and you’re still not so sure about why.

Never fear! There is a system to working out just how much protein you should be taking after you workout. Now, there are a lot of rumours and misconceptions about the % ratios to what you’re taking, and most of them are based in outdated truths. We want to make sure that you are getting the best information and the right information, so we went digging.

And when we say digging, we mean in the sense that we scoured the internet for the information that is the most up-to-date and relevant for you; we can tell you right now, there’s a lot of crap. True to our name, we cut the crap to give you what you need:

Here it is folks –

If you are an athlete or highly active person attempting to lose body fat while preserving lean muscle mass, a daily intake of 1.5-2.2g/kg body-weight (0.68-1g/lb bodyweight) is a good goal.

If you are an athlete or highly active person, or you are attempting to lose body fat while preserving lean mass, then a daily intake of 1.0-1.5g/kg body-weight (0.45-0.68g/lb bodyweight) is a good goal.

If you are sedentary and not looking to change body composition, a daily target of 0.8g/kg body-weight (0.36g/lb bodyweight) is a good goal.

Why do I even need protein?

Proteins are a part of the building blocks for life, they’re used to make everything that you’re made up of (even your toenails). Proteins are also used to make enzymes, hormones, neurotransmitters and other various compounds that your body uses to regulate function. Proteins are made up of amino acids; which look like a string under a microscope. Some of these aminos are internally sourced, however others you need to get from what you put into your body ie. the food you eat.

Protein supplements are typically used in conjunction with a proper diet (or as a band-aid to an average diet) to increase dietary protein intake. So if your input is less than your output, then you need to look into supplementation to ensure you maintain a healthy, nutritious, balanced diet. Generally, protein is used to help return the body back from a catabolic to an anabolic state. Taking protein supplement can help combat what most exercise physiologists call DOMS – delayed-onset muscle soreness, which is characterised by muscle tenderness and well as a loss of strength and motion post workout. We describe the function of protein in helping combat DOMS “Recovery” (you’ll see it on our packaging).

Some specific types of protein are made for certain scenarios, such as Casein protein for a slow-release protein and Whey protein for a faster release. They differ from Amino Acids as protein supplements will be a non-specific assortment of amino acids in large amounts, whereas Amino Acid supplementation is in lower doses, in isolation, and for specific purposes. Protein powders can be from either animal sources or plant sources, it is generally advised for vegans and vegetarians to consider protein supplementation due to the chance that they may not be intaking enough protein in their diet.

Well, can I eat too much protein?

Amino acids and some peptides are able to self-regulate their time in the intestines. An example of this is the digestive hormone CCK which, in addition to regulating appetite and satiety in response to food can also slow down intestinal contractions and speed in response to protein. CCK is released when dietary protein is present, and demonstrates a way in which the body can slow down digestion in order to absorb all present protein.

Protein and my Kidneys

Don’t worry about it if you have healthy kidneys and control your protein intake if you have damaged kidneys. It may be prudent to gradually increase protein intake to higher levels rather than jumping in both feet at a time, but there isn’t much on this topic.It is generally recommended to consume more water during periods when protein intake is being increased. Whether or not this has biological basis is not known, but it may be prudent to do.

Damaged or unhealthy kidneys: Restricted protein diets are recommended for those with kidney damage, as it slows the seemingly inevitable progression of kidney damage. If protein was not controlled for in those with renal damage, it would accelerate (or at least not reduce) the decline in function.

Protein and my Liver

In healthy persons and rats, there is no evidence to suggest a relatively normal style of protein intake is harmful to the liver when habitually consumed as part of the diet. There is some preliminary evidence, however, that very high protein refeeding after prolonged fasting (>48 hours) may cause acute injuries to the liver.

So what’s with the 30g of protein serving suggestion?

There really is no literature to indicate this number as a ‘holy grail’ of protein absorption. It may have arisen from looking at the rate of amino acid transporters, assuming 10g/hour as a standard, and applying that to the typical mini-meal approach to bodybuilder nutrition (with a meal every three hours).


There you have it folks!


As always, if you have any questions, please do not hesitate to contact one of our lovely PSA team members to give you a hand.





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