Understanding the Diseases Hunger Can Cause

November 17, 2025 •

5 min read

According to the World Health Organization (WHO), hunger is the single gravest threat to global public health, leading to widespread malnutrition. So, what diseases does hunger cause, and how does chronic food insecurity damage the human body over time? The devastating effects go far beyond an empty stomach, weakening organ systems and increasing susceptibility to illness.

Quick Summary

Chronic hunger and malnutrition trigger a cascade of adverse health effects, including severe nutrient deficiencies, a compromised immune system, and an increased risk of chronic diseases such as diabetes and heart conditions. It also significantly impacts mental health, leading to anxiety, depression, and cognitive impairments, particularly in children and vulnerable populations.

Key Points

Immune System Compromise: Hunger weakens the body's immune defenses, leaving individuals more susceptible to infectious diseases like pneumonia and measles.
Acute Malnutrition Disorders: Severe lack of food can lead to specific conditions such as Kwashiorkor (protein deficiency with edema) and Marasmus (calorie deficiency with severe wasting).
Micronutrient Deficiencies: Deficiencies in essential vitamins and minerals, or 'hidden hunger,' cause problems like anemia (iron deficiency), impaired brain development (iodine deficiency), and vision issues (vitamin A deficiency).
Chronic Disease Risk: Chronic food insecurity is linked to an increased risk of developing long-term conditions, including Type 2 diabetes and cardiovascular disease.
Psychological Damage: Hunger significantly impacts mental health, leading to anxiety, depression, irritability, and cognitive impairment, with long-lasting effects, especially on children.
Refeeding Syndrome Risk: The reintroduction of food after prolonged starvation must be carefully managed to avoid refeeding syndrome, a potentially fatal complication involving sudden electrolyte shifts.
Stunted Growth and Development: Chronic malnutrition during childhood impairs physical growth and cognitive development, causing irreversible damage.

The Progression of Hunger to Disease

When the body is deprived of sufficient food, it enters a state of starvation, triggering a metabolic shift to conserve energy. The body first uses up its readily available glucose stores, then turns to burning fat for fuel. When fat reserves are depleted, it begins to break down muscle tissue, leading to severe wasting. This process is not merely about weight loss; it is a systemic breakdown that causes critical physiological changes, paving the way for numerous diseases.

Acute Malnutrition Disorders

Extreme and sudden hunger can lead to severe acute malnutrition (SAM), which has two primary clinical presentations:

Kwashiorkor: This severe protein deficiency is characterized by edema (swelling) of the ankles, feet, and face, often giving the impression of a bloated belly. The swelling can mask the true extent of wasting. Other symptoms include an enlarged, fatty liver and changes to skin and hair pigmentation. Kwashiorkor frequently occurs when an older child is weaned from breast milk to a high-carbohydrate, low-protein diet.
Marasmus: Meaning "to waste away," marasmus results from a severe deficiency of both protein and calories. The primary symptom is extreme emaciation, with significant loss of fat and muscle mass. Individuals with marasmus appear gaunt, with loose, wrinkled skin. Unlike Kwashiorkor, edema is not typically present.

The Silent Threat: Micronutrient Deficiencies

Even with sufficient caloric intake, a poor-quality, monotonous diet can cause "hidden hunger"—a deficiency of essential vitamins and minerals. These micronutrient deficiencies can have devastating consequences, including:

Iron Deficiency: Leads to anemia, causing fatigue, impaired cognitive function, and increased risk of maternal mortality.
Iodine Deficiency: A major global concern, it can cause goiter, impaired cognitive development, and neurological damage in newborns.
Vitamin A Deficiency: Can cause night blindness, visual impairment, and a compromised immune system, increasing vulnerability to infectious diseases.
Zinc Deficiency: Results in a weakened immune response, stunted growth, and increased susceptibility to infections like pneumonia.

Impact on the Immune System and Infectious Diseases

Undernutrition severely compromises the body's immune system, making it less capable of fighting off pathogens. Protein and vitamin deficiencies, in particular, weaken both innate and adaptive immunity. This explains why infectious diseases thrive in areas affected by hunger. Malnourished children are significantly more likely to die from common illnesses such as diarrhea, measles, and pneumonia. A weakened immune system also hinders wound healing, prolongs illness, and can increase the viral load and transmissibility of diseases like HIV.

Chronic and Metabolic Health Issues

Beyond acute malnutrition, food insecurity is strongly linked to a higher risk of developing long-term chronic diseases. This paradox can be explained by the metabolic changes triggered by chronic hunger. Individuals who were undernourished as children often experience lasting metabolic alterations that increase their susceptibility to diet-sensitive chronic diseases later in life, including:

Type 2 Diabetes: Fluctuations in nutrient intake and metabolic stress can contribute to insulin resistance.
Cardiovascular Disease: Hunger can lead to high blood pressure and heart problems due to the strain on the cardiovascular system.
Obesity: In a phenomenon known as the "double burden of malnutrition," food-insecure households may rely on inexpensive, high-calorie, and low-nutrient foods, leading to overweight and obesity despite nutritional deficiencies.

Comparison of Key Effects: Hunger vs. Proper Nutrition


Aspect	Effects of Chronic Hunger	Effects of Proper Nutrition
Immune System	Severely weakened, increased susceptibility to infections, prolonged illness, and poor wound healing.	Strong and robust, effective at fighting pathogens, and promotes rapid recovery.
Physical Growth	Impaired growth and development in children, leading to stunting and long-term physical challenges.	Optimal physical growth, reaching full height and weight potential.
Cognitive Function	Impaired concentration, reduced cognitive abilities, and potential for developmental delays.	Improved memory, focus, problem-solving skills, and overall cognitive development.
Mental Health	High rates of anxiety, depression, irritability, and apathy, particularly in children.	Enhanced emotional stability, resilience, and overall mental well-being.
Metabolism	Slowed metabolic rate to conserve energy, leading to a higher risk of chronic diseases later in life.	Balanced metabolism, efficient energy conversion, and lower risk of metabolic disorders.
Cardiovascular Health	Dangerously low blood pressure and heart rate, increased risk of heart failure and arrhythmia.	Stable blood pressure and heart function, supporting long-term cardiovascular health.

Psychological and Neurological Toll

Beyond the physical, hunger takes a severe psychological and neurological toll. Constant preoccupation with food, coupled with nutrient deficiencies, profoundly affects mental health. Studies, including the famous Minnesota Starvation Experiment, have documented psychological symptoms such as depression, anxiety, apathy, social withdrawal, and irritability. In children, this stress can manifest as hyperactivity, aggression, and developmental trauma with lifelong consequences. The brain itself is affected, with deficiencies in nutrients like B vitamins and omega-3 fatty acids disrupting neurotransmitter balance and contributing to mood disorders. Chronic stress from food insecurity also increases the risk of Post-Traumatic Stress Disorder (PTSD).

Conclusion: Breaking the Cycle of Hunger and Disease

The links between hunger and disease are undeniable, creating a vicious cycle of poverty, malnutrition, and poor health that is difficult to escape. Acute and chronic malnutrition, compromised immune function, infectious diseases, chronic metabolic conditions, and severe mental health issues are all direct consequences. Breaking this cycle requires a multi-faceted approach that addresses not only the immediate need for food but also the underlying causes of food insecurity, such as poverty, conflict, and climate change. Early and adequate nutritional intervention, especially in the first 1,000 days of a child's life, is crucial for preventing irreversible damage and securing long-term health. As documented by organizations like Action Against Hunger, addressing hunger is a public health imperative that can prevent immense suffering and save countless lives.

Addressing Hunger and Malnutrition

Combating the diseases caused by hunger is a global health priority that requires comprehensive strategies. Programs providing nutritional assistance, promoting breastfeeding, and strengthening healthcare systems are all essential components. Initiatives that improve food security and nutrition education are also vital for preventing both undernutrition and the paradoxical rise of obesity in food-insecure populations. Organizations like the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) are actively working towards meeting global nutrition targets and building sustainable, resilient food systems.

Frequently Asked Questions

Kwashiorkor is primarily a protein deficiency causing edema (swelling), especially in the abdomen, which can disguise the wasting. Marasmus is a severe deficiency of both protein and calories, resulting in extreme emaciation and a visibly wasted appearance.

Yes, this is known as the 'double burden of malnutrition.' Food-insecure people in developed nations often rely on inexpensive, high-calorie, and low-nutrient processed foods. This can lead to obesity and metabolic issues alongside micronutrient deficiencies.

Hunger and malnutrition severely weaken the immune system by depriving it of the necessary protein, vitamins, and minerals to function properly. This impairs the production of immune cells, reducing the body's ability to fight off infections and heal wounds.

Childhood hunger can cause irreversible stunted growth, impaired cognitive development, and a higher risk of chronic diseases like diabetes and heart disease in adulthood. It also has severe and lasting negative effects on mental health.

Yes, hunger and food insecurity are strongly linked to mental health issues. Chronic hunger causes significant stress, anxiety, depression, and irritability. For children, it can also lead to developmental trauma and behavioral problems.

In the final stage, the body has depleted its fat and muscle reserves and breaks down protein from critical organs. This can lead to severe organ failure, electrolyte imbalances, heart problems, and a complete collapse of the immune system, often resulting in death from infection or cardiac arrest.

Refeeding syndrome is a potentially fatal complication that can occur when a starving person is reintroduced to food too quickly. It causes a rapid and dangerous shift in fluids and electrolytes, which can overwhelm the body and lead to heart failure, respiratory distress, or death if not carefully managed.