Overview

• Protein deficiency can occur when your diet does not give you enough protein or a health problem affects its absorption or causes protein loss.

• Severe undernutrition involving protein and energy can lead to kwashiorkor or marasmus, which may cause swelling, muscle loss, and weakness.

• Common signs include muscle weakness, unexplained weight loss, slow wound healing, frequent infections, and changes in hair or skin.

• Doctors consider your diet, health history, physical signs, and selected tests; no single blood test confirms every case.

• Treatment depends on the cause and severity and may include protein-rich foods, care for underlying illness, or supervised nutritional support.

 

Quick Answer: Which Diseases Are Linked to Protein Deficiency?

Kwashiorkor and marasmus are severe forms of undernutrition involving a shortage of protein and other nutrients. Kwashiorkor causes swelling; marasmus causes severe loss of body fat and muscle from too little food energy. A mixed form has both. These conditions mainly affect young children, though severe malnutrition also affects adults.

If you are worried about hair loss, tiredness, or weaker muscles, do not assume you have one of these diseases. These symptoms have many possible causes. Understanding your diet and any health changes is a better starting point than buying supplements.

 

What Is Protein Deficiency?

Protein deficiency means your body is not getting enough usable protein to meet its needs. This may happen because you eat too little, cannot absorb nutrients properly, or lose protein through an illness.

Your body breaks protein down into smaller parts called amino acids. It uses these to build and repair tissues, including muscles. You can get protein from both plant and animal foods.

When protein and energy from food are too low, doctors may use the term protein-energy malnutrition, or PEM. It is a wider nutrition problem, rather than simply a lack of one food or nutrient.

Protein Deficiency Diseases Chart

These names describe severe forms of undernutrition.

Disease or condition	What it means	Main signs
Kwashiorkor	Severe malnutrition with swelling caused by fluid build-up	Swollen feet and legs; skin or hair changes; muscle loss that swelling may hide
Marasmus	Severe shortage of food energy and nutrients, including protein	Marked weight loss, very little body fat, visible muscle loss and weakness
Marasmic kwashiorkor	A mixed form with severe wasting and nutritional swelling	Major loss of fat and muscle, together with swelling

All three need medical care. Kwashiorkor is often described as a protein deficiency disease, but its causes are more complex than a lack of protein alone.

Protein Deficiency Diseases in Adults: Symptoms to Watch For

In adults, doctors assess food intake, weight changes, and health before diagnosing undernutrition.

Possible signs include:

• Losing weight without trying: Clothes may become looser over time.

• Losing muscle or strength: Everyday tasks may feel harder.

• Ongoing tiredness: You may feel weak or low in energy.

• Slow wound healing: Cuts or wounds may take longer to heal.

• Getting ill often or recovering slowly.

• Hair and skin changes: Hair may become brittle, and skin may become dry.

• Swelling: Severe malnutrition can cause fluid to collect in the feet, legs, or belly.

These signs are not specific to protein deficiency. Also, being a normal weight or overweight does not rule out poor nutrition. 

Symptoms of Protein Deficiency in Females

The main signs are similar to those in males: muscle loss, weakness, unplanned weight loss, and poor healing. Pregnancy and breastfeeding increase protein needs, so food intake may need to change during these stages.

Symptoms of Protein Deficiency in Males

Men can have the same warning signs. Reduced strength or muscle size alone cannot show whether the cause is low protein intake, reduced activity, or an illness. Doctors consider these changes alongside food intake and overall health.

Hair loss alone does not prove protein deficiency in either sex. Iron deficiency, thyroid disease and several other conditions can also cause hair loss.

What Causes Protein Deficiency?

The main causes involve food intake, absorption, and illness:

• Eating too little overall. Poor appetite, strict weight-loss diets, eating disorders, or difficulty getting enough food can reduce protein and calorie intake.

• Eating too few protein-containing foods. A diet based mainly on rice or roti, with very little dal, beans, soy, dairy or other protein sources, may fall short. Rice and roti do contribute some protein; variety and quantity matter.

• Problems absorbing food. Conditions such as coeliac disease or Crohn’s disease can stop the gut from taking in enough nutrients.

• Illness or recovery. Serious illness, burns or surgery may increase the body’s needs while also making it harder to eat enough.

Some kidney diseases cause protein to leak into urine. Advanced liver disease can reduce the production of albumin, a blood protein. Low blood protein is therefore not always a sign of eating too little protein. 

How Much Protein Do Adults Need Each Day?

ICMR–NIN gives a reference allowance of 0.83 grams of protein per kilogram of body weight per day for healthy adults, assuming good-quality protein.

Body weight	Approximate daily amount at 0.83 g/kg
50 kg	42 g
60 kg	50 g
70 kg	58 g

The same guidance uses 1 g/kg/day for cereal-based diets with lower protein quality. This does not mean every vegetarian diet is low in quality. A varied diet can provide the amino acids your body needs.

These are reference amounts, not a treatment plan. Pregnancy, breastfeeding, intensive training, and illness may change your needs. If you have kidney disease, ask your doctor or dietitian how much protein is right for you.

Which Indian Foods Can Help You Get Enough Protein?

Everyday foods can help you meet your protein needs. Choose options that suit your budget, food preferences, and health.

Food group	Everyday options
Pulses and beans	Moong, masoor, chana, rajma and lobia
Soy foods	Tofu, soybeans and soy chunks
Dairy	Milk, curd and paneer
Eggs, fish and meat	Eggs, fish and chicken, if you eat them
Nuts and seeds	Peanuts, almonds, sesame and pumpkin seeds

A vegetarian diet can provide enough protein when it includes enough food and a range of sources. Use nuts and seeds alongside foods such as dal, beans, soy, or dairy.

Simple Ways to Add Protein to Meals

• Breakfast: Besan chilla with curd, idli with sambar, or eggs with roti or toast.

• Lunch: Dal, chana or rajma with rice or roti and vegetables.

• Snack: Roasted chana, curd, or a portion of peanuts.

• Dinner: Tofu, paneer, soy chunks, fish or chicken with your usual meal.

Cereals and pulses provide different amino acids, so combinations such as dal–rice and roti–chana improve the overall protein quality of a diet. Include protein-containing foods across the day. The amount you eat still matters; these examples are not a fixed meal plan.

Also Read: 20 High-Protein Vegetables to Boost Muscle Mass and Stamina

How Do Doctors Check for Protein Deficiency?

There is no single blood test that can tell whether you eat enough protein. A doctor starts by asking about your meals, appetite, recent weight changes, symptoms, and medical history. They may check muscle loss, strength, and signs of swelling.

Tests are chosen to investigate a likely cause or another explanation for your symptoms.

Test or assessment	When it may help	What it cannot tell you
Total protein and albumin blood tests	Investigating abnormal blood protein, swelling or suspected liver or kidney disease	They do not directly measure dietary protein intake or muscle protein.
Kidney tests and a urine protein or albumin test	When symptoms or other findings suggest protein loss through the kidneys	Kidney blood tests alone do not directly measure protein leaking into urine.
Liver function test	When the history, examination or other results suggest liver disease	An abnormal result does not by itself show dietary protein deficiency.
Complete blood count (CBC)	Checking for anaemia when tiredness, weakness or other findings make this relevant	A CBC does not measure protein intake.

Blood protein results need careful interpretation. Albumin can fall during inflammation or illness, even when food intake is adequate. Low albumin does not prove dietary protein deficiency, and normal albumin does not rule out malnutrition.

If ongoing diarrhoea, gut symptoms or unexplained nutrient deficiencies suggest coeliac disease, a doctor may request tTG-IgA and total IgA blood tests. Do not start a gluten-free diet before discussing testing, as removing gluten can affect the results.

You do not need every test listed here. If albumin or total protein is already included in a prescribed panel, ask whether a separate test is needed. Testing should answer a medical question, rather than serve as a routine protein-deficiency checklist.

How Is Protein Deficiency Treated?

Treatment depends on the cause and how unwell the person is.

1. Improve Food Intake

If intake is too low, a dietitian can help you add enough protein and overall food energy. Small, frequent meals may help when appetite is poor. Protein alone cannot replace the other nutrients your body needs.

2. Treat the Underlying Problem

A digestive condition, ongoing illness, swallowing problem, or kidney protein loss needs its own treatment. Adding protein powder will not fix every cause of low blood protein or weight loss.

3. Use Nutrition Supplements When Needed

Some people need prescribed nutritional drinks or other support if food is not enough. Many healthy adults can meet their needs through food. A doctor or dietitian can advise whether a supplement would help. 

4. Get Medical Care for Severe Malnutrition

Severe malnutrition may need hospital care and carefully planned feeding. If you have eaten little or nothing for more than five days, or have severe weight loss, seek medical advice before sharply increasing food or supplements.

Restarting nutrition too quickly can cause dangerous changes in minerals in the blood. This is called refeeding syndrome. People at risk need supervised treatment.

When Should You See a Doctor?

Arrange an assessment if you have ongoing, unexplained weight loss, loss of muscle or strength, poor appetite, trouble swallowing, persistent diarrhoea or swelling.

Seek urgent care for breathing difficulty, confusion, fainting or severe weakness. Do not wait for a nutrition test if you are seriously unwell.

If your doctor recommends a laboratory test, you can check the prescribed test on the Redcliffe Labs website. Share the results with your doctor so that treatment addresses the cause.

Frequently Asked Questions

Can Eating Three Meals a Day Prevent Protein Deficiency?

Not always. What you eat and how much you eat matter as well as meal frequency. Include suitable protein foods, such as dal, beans, soy, dairy, or eggs, alongside enough overall food.

Can Protein Deficiency Cause Hair Loss?

Yes, too little protein can contribute to hair loss. However, hair loss has many causes, including iron deficiency, thyroid disease, and stress. Extra protein will not treat every cause of hair loss. Treatment depends on what is causing it.

Does Swelling Mean I Need More Protein?

No. Severe malnutrition can cause swelling, but kidney, liver, and heart problems can also cause it. Get unexplained swelling assessed instead of treating it yourself with protein supplements.

Do Vegetarians Need Protein Powder?

Not automatically. Pulses, soy, dairy, nuts, seeds and grains can contribute to a varied vegetarian diet. A supplement may help when food intake cannot meet your needs, but it is not essential for everyone.

How Long Does Recovery Take?

There is no single recovery time. It depends on the severity, cause, other illnesses, and response to treatment. Follow-up checks of food intake, weight, and strength help your care team assess progress.