How Much Protein Should I Eat?

The amount of protein one should consume is often debated. There is a sea of information out there and it's difficult to determine what is right. One thing is certain though; protein is important to our health as it's the building block for our tissues!

Proteins (amino acids) are molecules that play many vital roles in the body. Often we think of 'muscle' when the topic of protein comes up. However, it's more than just muscle. They are responsible for the function, structure, and regulation of all the tissues and organs. 

Proteins have various functions. For example, actin is a protein that provides structure and support for cells. Ferritin is another protein that serves as a transporter and storage unit (stores iron). As it relates to body composition, diets higher in protein are twice as effective in making changes to the body and lowering body fat. This is due to its thermogenic properties as well as its ability to increase satiety. Additionally, studies have found that higher protein meals result in reduced energy intake later in the day...so essentially you eat less. Hopefully you see how important protein is in our diet. Now we get to the good stuff...how much do I need?

How much do I need?

Alright, before we get there, let's talk about what we know. The recommended dietary allowance (RDA) suggests 0.8 grams of protein per kilogram of body weight per day. However, this is the minimum amount of protein needed to maintain nitrogen balance in the body. We're talking about surviving, not thriving here. This doesn't even factor in maintaining or increasing lean muscle mass, which is crucial to our health. 

Protein intake can get pretty complicated because it is based on many factors such as age, sex, and activity level. For example, we absorb less protein as we get older. This occurs because we tend to be less active as we age. The less active we are the less efficient our bodies will be at synthesizing protein, which is referred to as anabolic resistance. We do know that if you under-consume protein, the body will just catabolize its own tissue to source amino acids. This leads to loss in muscle mass and contributes to metabolic dysfunction and conditions such as sarcopenia (age related muscle loss). Furthermore, studies have shown accelerated bone loss for individuals with osteoporosis that develop sarcopenia. Side note: This is why it's never too late to start lifting weights! It's essential!



An easy way to determine how much protein to consume is by referencing the Acceptable Macronutrient Distribution Range (AMDR). The AMDR is based on evidence that consuming greater or less than specific macronutrient ranges may be associated with nutrient inadequacy and increase the risk of developing chronic diseases, such as coronary heart disease, obesity, and diabetes.



The AMDR suggests 10-35% of caloric intake as protein, which is roughly 1.0-3.7 grams per kilogram of weight per day. Keep in mind that 1.0 g/kg/d is fairly on the low end and is reserved for those who are largely sedentary. However, if you are looking to increase lean muscle mass and currently engage in resistance training or other forms of exercise, then you want to consider a greater intake. To support muscle growth, strength, and general protein turnover (i.e. skin, hair, soft tissues), studies have shown that you want to target 1.2-2.2 g/kg/d. This comes out to about 1 gram of protein per pound of body weight. You want to consider a higher protein intake the older and/or the more active you are to account for lower absorption rates and decreased protein synthesis. Simple put, quantity and quality need to increase with age!

Bioavailability

Bioavailability is one of the most important aspects of protein intake. It is the amount of a nutrient that we can digest and absorb into our system. The figure below is sourced from the Protein Digestibility-Corrected Amino Acid Score (PDCAAS) system. It's a method used to evaluate both the amino acid profile and its digestibility. 



When a protein source has greater bioavailability, you can actually eat less of it because you absorb more. Protein sources that have poor absorption rates will often lead you to consume more food (and calories) to obtain the same nutritional outcome. 

What, When, How?

Alright, there are some other factors to consider. Protein quality is important as well as when you consume it. Protein quality refers to the type of amino acids you are consuming as well as bioavailability, which we discussed above. To keep this short, I will just discuss what you need to know.



Quality: Although there are many amino acids that the body requires to function, there are 9 that are essential that you must get from food. Of those, the following 3 are most important: methionine, lysine and leucine. These amino acids are critical to protein synthesis, recovery, immune function, and collagen production. However, unless you plan to research everything you eat to understand its amino acid profile, it's just best to vary your daily protein sources. For example, beef, salmon, and eggs are good sources of leucine (which is the gatekeeper of protein synthesis). Tofu is a great source for methionine. Varying your protein sources might look like boiled eggs and yogurt for breakfast, a tofu salad for lunch, and fish and vegetables for dinner.



Amount: Keep the math simple by targeting 25-30 grams of protein per meal. Again, this is where bioavailability comes in. Let say you decided to add 1 ounce of almonds to a salad to add another 6-8 grams of protein. Based on its digestibility, you will likely only absorb less than half of that. It's better to eat almonds for their content of healthy fats rather than protein. You are better off adding a hard-boiled egg as it will have far greater absorption.



If you are fasting or limit your meals to let's say 1-2 per day, then you have to increase the amount of protein you consume each sitting. Again, target 1 gram of protein per pound of mass per day. If you are fairly active or if you have poor recovery then shoot for a little more.



Timing: We are typically burning more fat at night and first thing in the morning. However, we are also in a catabolic state...meaning, the body is breaking down muscle tissue. In order to move to an anabolic state (i.e. building), you would need to consume protein in the morning. Generally, you want to front load your protein early and spread it throughout the day. This is a much better way to stimulate muscle protein synthesis all while regulating your hormone response rather than eating all of it later in the day. Unfortunately, a majority of people eat most of their protein in one meal and it's usually at dinner. So ditch the donut in the morning and swap it out for high quality protein!



Again, no need to make it complicated. Stick with whole foods for protein, make sure you vary the sources, and spread your intake throughout the day while front loading most of it. Good luck! :) Reach out to the Women’s Lift Lab if you need help!