What Happens if You Don't Eat Enough Protein? 8 Signs - Health.com

Protein deficiency is not consuming enough protein to support your body's needs. Protein is an essential macronutrient—a nutrient the body needs and uses in large amounts. It provides structure and support to cells, helps cells communicate, and protects the body from viruses and bacteria. Protein also helps children, teenagers, and pregnant people with growth and development.

A protein deficiency can lead to conditions like kwashiorkor and marasmus. Kwashiorkor is a severe protein deficiency accompanied by edema (swelling) in the arms and legs. Marasmus is severe malnutrition (a lack of or imbalance in food or nutrient intake) caused by not consuming enough calories.

A lack of protein in the diet can greatly affect health. Signs and symptoms of protein deficiency include swelling, stunted growth, and a weakened immune system.

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One of the main signs of kwashiorkor is swelling on both sides of the body. People with kwashiorkor have low levels of a substance called albumin. Albumin helps to keep fluid inside the blood vessels. A lack of albumin can make it difficult for the body to balance fluid in blood vessels. As a result, the body tries to hold onto more water and sodium, which causes swelling.

Protein is a major component of skin and hair, which is why protein deficiency can greatly affect skin and hair health.

A lack of protein can cause your skin to appear paler, as well as drier or flakier. Your hair may appear more brittle and may break more easily. You may also experience hair loss or graying.

Symptoms of kwashiorkor include:

• Dry, thin, or peeling skin
• Skin folds due to weight loss
• Skin lesions or dermatitis on ears, armpits, groin, and genitals
• Hair that's dry or falls out easily

Hair and skin changes do not usually occur with marasmus. However, low protein intake can also trigger telogen effluvium, a condition that leads to excessive hair shedding and hair loss.

A severe protein deficiency can impair your immune system. Protein helps make antibodies that protect you from infection and other illnesses. Protein deficiency leads to fewer antibodies, which can increase your risk of developing an infection.

Low protein intake often means lower intake of other nutrients. For example, one meta-analysis of over 11,000 adults aged 51 and older found that adults who didn't meet the estimated average requirement (EAR) of protein were more likely to fall below the EAR for a number of vitamins and minerals.

A lack of nutrients is associated with inflammation and oxidative stress, which can affect the immune system. Oxidative stress happens when there are more free radicals in the body than there are antioxidants available to remove them. Free radicals are produced during digestion. They can damage cells, trigger changes in genes, accelerate aging, and increase the risk of various conditions like heart disease and diabetes.

Skeletal muscle, the muscle attached to bones, is the type of muscle that helps your body move. Consuming higher amounts of protein can help build and maintain skeletal muscle mass and strength.

Your body breaks down skeletal muscle tissue for energy when there's not enough protein for use. This leads to muscle atrophy (decrease in muscle mass). Even minor muscle loss can affect your movement and strength.

Sarcopenia is the progressive loss of muscle mass and strength. It usually develops due to the natural aging process. Consuming adequate protein (about 1.6-1.8 grams of protein per kilogram of body weight per day) is one way to slow the progression of sarcopenia.

Protein is an essential component of muscles and bones. Your bones are made primarily of a type of protein called collagen. Therefore, a protein deficiency can decrease muscle and bone mass, leading you to feel tired and weak.

Protein from calcium-rich foods is required for bone growth, especially for young children. Bone mass, or bone mineral density (BMD) is largely genetic. Consuming adequate protein helps children reach their optimum genetic potential for bone mass.

Protein is also important for bone maintenance in older adults who have or are at a higher risk of osteoporosis, a condition that causes porous, weak bones that break easily. One meta-analysis of 13 studies found that adults over the age of 65 with a higher protein intake had a lower risk of bone fractures.

Protein is essential for growth. Growth stunting, or impaired growth and development, can occur when children don't get enough protein. This is one of the symptoms of kwashiorkor. Growth stunting can affect health and well-being in multiple ways, including:

• Poor performance in school
• Impaired cognitive development
• Increased risk of nutrition-related chronic health conditions

It's important to treat protein deficiency early, especially in children. Early treatment can reduce the risk of complications like permanent physical disabilities.

Many factors can contribute to weight loss as a result of protein deficiency. People who have marasmus may experience reduced heart function, which can lead to weight loss. Reduced heart function can also increase a child's risk of developing an arrhythmia, or irregular heartbeat.

Eating a lower protein diet can also lead to weight gain. For example, protein is often more satiating than carbohydrates, meaning you feel full for longer periods of time after eating protein. Therefore, eating more protein might lead to lower caloric intake overall.

More research is needed to determine how protein affects weight, but shorter-term research studies demonstrate that a high-protein diet can contribute to weight loss and prevent weight regain.

Anemia is a common symptom of marasmus. Anemia is a condition where your body has a reduced number of red blood cells or hemoglobin, the protein that helps your red blood cells transport oxygen from your lungs to the rest of your body. Your body needs iron to make oxygen-rich red blood cells.

Anemia is often treated with iron supplements or by eating more iron-rich foods.

About one billion people worldwide do not get enough protein in their diets. It's commonly seen in areas with a limited food supply and lower levels of education about healthy eating. For example, about 30% of children in Central Africa and South Asia have a protein deficiency.

Protein deficiency is not very common in the United States. However, some people are at a higher risk, including:

• People with cancer
• Older adults, specifically those who receive home-delivered meals or are in a long-term care facility
• Children who are abused or severely neglected
• People who follow diets that cut out sources of protein-rich foods

Protein needs vary depending on factors like age, weight, and physical activity levels. In the U.S., the recommended dietary allowance (RDA) for protein is 0.8 grams per kilogram of body weight, or 0.36 grams per pound.

The RDA is the minimum amount of protein necessary to prevent muscle loss. Many people require more protein to maintain optimal health.

Here are some basic protein recommendations:

• Experts suggest that physically active people aim for a daily protein intake between 1.2-2.0 grams per kilogram (0.54-0.9 grams per pound) daily, which is much higher than the current RDA.
• Some people, like athletes, may need even more protein to maintain muscle mass and support health. For example, some research shows that certain athletes' protein needs can exceed 2 grams per kilogram (0.9 grams per pound).
• People who are pregnant or breastfeeding, older adults, and people with certain medical conditions, like cancer, require more protein than the general population.

Not everyone should consume high amounts of protein in their diet. For example, too much protein can negatively affect conditions like kidney disease. Talk to your healthcare provider about how much protein you need.

There are plenty of animal and plant-based protein protein sources from which to choose.

Animal sources of protein include:

Plant-based sources of protein include:

Try to limit red meat and processed meat, as high amounts can increase your risk of conditions like heart disease. Also, talk to your healthcare provider before trying protein powders or supplements. Dietary supplements are minimally regulated by the FDA, and their effects vary from person to person.

Meal Ideas

If you're concerned about your protein intake, try adding at least one protein source to every meal and snack, starting with breakfast. For example:

• Add nut butter to apple slices and sprinkle the slices with hemp seeds
• Mix protein powder into your morning oats
• Top your salad with chicken, fish, hard-boiled eggs, or beans
• Swap your morning bowl of cereal for a higher-protein option like an egg and vegetable omelet or Greek yogurt topped with pumpkin seeds and berries

Reach out to your healthcare provider if you're concerned you may not be getting enough protein in your diet or if you or someone in your care has symptoms of kwashiorkor or marasmus. Getting medical care early on can help prevent possible complications.

Your healthcare provider might also refer you to a registered dietician (RD), a certified healthcare professional who specializes in nutrition. 

Protein is essential to health. It helps with growth and development, and it helps repair cells and make new ones. Protein deficiency can cause symptoms such as swelling, stunted growth, a weakened immune system, skin and hair changes, and bone and muscle loss.

The amount of protein you need depends on factors like age and activity levels. You can get more protein in your diet by adding foods like beans and legumes, meat, seafood, eggs, and nuts. Reach out to your healthcare if you're concerned that you or someone in your care is not eating enough protein.