There is some controversy surrounding the maximum amount of protein that can be used to build lean tissue in a single intake for those doing regular resistance training.
The answer to your initial question "can we absorb more than 30g of protein?" the answer is that it is possible.
Although the intake of 20-25g of protein may maximize muscle protein synthesis for some individuals, this doesn't mean that any excess beyond this amount is wasted.
Consuming more than 25g of protein per meal is therefore not necessarily useless, but its effectiveness depends on the source of the protein, its speed of digestion and the presence of other macronutrients in the meal.
Some of these surplus amino acids can be used for tissue-building functions, although some can also be oxidized.
Optimal intake can also vary according to individual characteristics, the type of protein and its combination with other macronutrients.
Here are the key points and conclusions based on the scientific study by Brad Jon Schoenfeld & Alan Albert Aragon published in 2018 in Journal of the International Society of Sports Nutrition.
Fast vs. slow proteins
Muscle protein synthesis is maximized in young adults with an intake of around 20-25 g of a high-quality protein.
However, this applies specifically to fast-digesting proteins without the addition of other macronutrients.
The terms "fast proteins" and "slow proteins" refer to the speed at which proteins are digested and absorbed by the body.
This rate of absorption can influence how the body uses these proteins for muscle repair and growth, as well as other functions.
Proteins are rapidly digested and absorbed by the body. This leads to a rapid and pronounced increase in amino acids in the blood after consumption.
Whey, for example, is the most common example of a fast protein.
Given their rapid digestion, whey is often consumed immediately after a workout to rapidly deliver amino acids to muscles and support recovery and growth.
Slow proteins are digested and absorbed more slowly, leading to a more gradual and sustained release of amino acids into the bloodstream.
Casein, another dairy protein, is a typical example of a slow protein. It coagulates in the stomach, delaying digestion and absorption.
Thanks to their slow absorption, proteins such as casein are often consumed before bedtime to provide a constant source of amino acids during sleep, a period when the body repairs and regenerates itself.
Important for athletes and active people:
The combination of fast and slow proteins can be beneficial for those looking to optimize muscle recovery and growth. For example, after a workout, consuming fast proteins can provide an immediate supply of amino acids for repair, while adding slow proteins can ensure a sustained supply of amino acids to prolong the anabolic response.
It's also important to note that the combination of protein with other macronutrients, such as fat and fiber, can influence absorption speed.
These combinations can transform a "fast protein" into a more moderate or slow source of amino acids, depending on the other components of the meal.
[/et_pb_toggle][/et_pb_column][/et_pb_row][/et_pb_section]Slower-acting protein sources, especially when consumed with other macronutrients, could delay absorption and therefore potentially enhance utilization of constituent amino acids.
What's the maximum protein per meal?
To date, the literature indicates that the total daily protein intake required to maximize muscle mass and strength gains induced by resistance training is around 1.6 g/kg.
However, this should not be seen as a strict limit. A recent meta-analysis suggests an upper limit of 2.2 g/kg/day , and higher consumption does not appear to cause any particular health problems.
Based on current evidence, their study concludes that protein should be consumed at a target intake of 0.4 g/kg/meal over at least four meals to achieve a minimum of 1.6 g/kg/day.
Using the maximum daily intake of 2.2 g/kg/day spread over these four meals, this would require a maximum of 0.55 g/kg/meal.
In other words, this means a minimum dose of around 32 grams of protein per meal 4 times a day if you weigh 80 kg.
Here's a table showing the minimum and maximum protein intake per day and per meal for each weight range from 50 to 110 kg (in 10 kg steps):
| Weight (kg) | Minimum consumption (g/day) | Max consumption (g/day) | Prot per meal (min) | Prot per meal (max) |
|---|---|---|---|---|
| 50 | 80.0 | 110.0 | 20.0 | 27.5 |
| 60 | 96.0 | 132.0 | 24.0 | 33.0 |
| 70 | 112.0 | 154.0 | 28.0 | 38.5 |
| 80 | 128.0 | 176.0 | 32.0 | 44.0 |
| 90 | 144.0 | 198.0 | 36.0 | 49.5 |
| 100 | 160.0 | 220.0 | 40.0 | 55.0 |
| 110 | 176.0 | 242.0 | 44.0 | 60.5 |
As you can see, the majority of daily requirements above a certain weight involve consuming more than 30 grams of protein per meal.
So, for meals exceeding 25g of protein, the protein source and combination with other macronutrients are crucial to maximize amino acid utilization and support muscle synthesis.
If the source is a fast-digesting protein (such as whey), consuming this protein with fats or carbohydrates could help slow down its absorption and maximize amino acid utilization.
From the point of view of optimizing protein synthesis, it's therefore not a good idea to look for a product with as few carbohydrates as possible. We come back to this subject in our article on taking carbohydrates with your proteins.
Finally, although consuming higher doses of protein leads to greater oxidation of amino acids (AAs), this doesn't mean that all the extra AAs are oxidized. Some are used to build different tissues.
