How Much Protein You Really Need (According to Science)?

Protein is quite the trendy macronutrient right now, with companies peddling everything from protein powder to pancakes (I happen to be 
one of those peddlers).

Before you decide to invest your hard-earned dollars in an admittedly expensive protein powder, it’s important to ask a fundamental question:

How much protein do you actually need?

To answer it, we’ll delve into the latest and greatest research papers and distil the findings in a (hopefully) easy-to-digest format (pun intended).

Here goes …

Your Protein Requirements Will Depend on 4 Factors

First off, the amount of protein you should ingest each day depends on several things:

  1. Your current body composition. It should come as no surprise that people who are in great shape need more protein to maintain their physique. That’s because the more muscular you are, the more amino acids you need to maintain that stellar body composition. How do you know what your body composition is? Go to a gym or personal trainer that offers body composition analysis. 
  2. Your age. As we touched on, clearly younger athletes are going to require more protein. But what many folks don’t realize is the older you get, the more protein your body needs to maintain its muscle mass. Elderly adults, in particular, should get about 30-35% of their daily calories from protein. Research shows that current recommended dietary allowance for protein (0.8 g/kg of bodyweight per day) may be inadequate for maintaining muscle in older adults. 
  3. How active you are. The more exercise you get, the more protein your body needs. Studies show that athletes and people who exercise often can benefit from up to 2 g/kg of body weight per day. 
  4. Your hormone levels. If you have high levels of growth hormone and insulin-like growth factor 1 (IGF-1), your body will use protein more efficiently than a person with lower levels. These hormones decrease as you age, which is one of the reasons why older adults need more protein.

So with those things in mind, here’s how much protein you actually should be ingesting …

How Much Protein Do You Need?

The current recommendation for protein intake is 0.8 grams per kilogram (or around 0.36 grams per pound) of body mass in generally healthy adults.

However, this protein intake recommendation is only to prevent protein deficiency and maintain nitrogen balance in the body. In other words, if you’re looking to build lean muscle tissue, then you will need more.

While .8 g per kg works for the average adult, it’s definitely not optimal for hardcore exercisers or older adults, as we’ve seen.

Studies show that athletes, active people, and older individuals can benefit from daily protein intake of 1.4 – 2.0 g/kg of bodyweight.

One study, in particular, published in the Journal of the International Society of Sports Nutrition, found that 1.8 grams per kilogram of body weight was an optimal number to see favorable improvements in body composition in athletes. For a 150-pound person, that equals 122 grams of protein each day.

In Summary

  • Most people can stick with the .8 g/kg of bodyweight recommendation. For a 150-pound adult, that equals 54 grams of protein per day.
  • Older adults and non-athletes need at least 0.8 g/kg of bodyweight to maintain current body composition. To improve body composition, you should be somewhere between .8g/kg and 1.8 g/kg.
  • Athletes and avid exercisers need at least 1.8 g/kg of bodyweight (122 grams/day for a 150-pound person.

Scott Christ

Scott Christ is founder of a small business called Pure Food Company, which is dedicated to creating the world’s healthiest protein powders and making a positive impact. Get free recipes, coupons, and articles like this delivered to your inbox periodically when you subscribe to our Clean Eater Community (it’s free).

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