What Happens to Your Body When You Don't Eat Enough Protein

These four scary side effects could stem from a lack of protein in your diet. Here's what to do about it.


Protein is essential to a healthy diet. This macronutrient makes up the major component of our cells and provides the essential amino acids that keep our bodies up and running. Even with this knowledge in mind, most of us aren't getting as much protein as we should be. Studies show that about 40% of Americans are not consuming enough protein.

According to the United States Department of Agriculture, men and women should consume approximately 0.8 grams of protein daily for every kilogram of body weight (FYI- That's about 0.36 grams per pound, so a 150-pound woman would be looking to get about 54 grams of protein each day.). And if you're strength training or exercising regularly—you may need a little more.

Why Do We Need to Eat Protein?

Protein plays a very important role in our bodies. It's one of the main building blocks of bones, muscles, cartilage and skin. Protein also helps to supply our bodies with vital nutrients and aids in digestion by producing enzymes that help to break down food into molecules for a wide range of bodily functions.

What Happens If You Don't Eat Enough Protein?

1. You're more likely to get stress fractures.

Besides calcium, our bones also need protein. Bones undergo continuous restoration, and because of this, we need an adequate supply of protein to support this process. When we aren't getting enough protein to fuel our vital organs, our bodies start to borrow protein from other areas, which includes that stored in our skeletal muscle tissue. Without strong skeletal muscle tissue, our bones are more susceptible to injuries like fractures.

2. It may weaken your hair and nails.

Did you know that proteins such as keratin, collagen and elastin are responsible for healthy hair and nails? Keratin is a protein that is found in your skin, hair and nails. It's responsible for providing strength and structure.

Collagen is the most abundant protein in your body. It's one of the major building blocks of bones, skin, muscles and ligaments.

When you hear elastin, the word elastic may come to mind, which would be an accurate correlation. Elastin is very flexible and its high elasticity allows many tissues in your body to return to their original shape after being stretched.

3. Your immune system may start to weaken.

Most people may not realize this, but protein is very beneficial to building a healthy immune system. Protein is one of the building blocks of antibodies, which are produced by the body's immune system to help fight off bacteria and viruses. Without these antibodies, bacteria and viruses would be free to roam and infect your body with diseases.

4. You may feel less satisfied after meals.

Feeling hungry after you've eaten a meal? It may be due to a lack of protein at mealtime. If you don't eat enough protein, you may notice that you feel unsatisfied after meals and tend to get hungrier throughout the day. Studies show that consuming an adequate amount of protein can increase the release of an appetite-regulating protein, therefore keeping you fuller longer.

The Bottom Line

Protein has many important roles in the body. It's one of the main building blocks of bones, muscles, cartilage and skin, and it helps to supply our bodies with vital nutrients. Without an adequate amount of protein, you may be prone to stress fractures, brittle hair and nails, a weakened immune system and feeling unsatisfied after meals. To prevent this from happening, be sure to get consume an adequate amount of protein daily. Check out our healthy high-protein recipes for delicious meal inspo!

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