Which top causes of death are directly or indirectly related to nutrition?

January 8, 2026 •

4 min read

Nearly half of all deaths among children under five years of age are linked to undernutrition, highlighting a stark connection between nutrition and mortality. For adults, the relationship is equally profound, with imbalances, deficiencies, and excesses in a person's diet contributing significantly to the most prevalent noncommunicable diseases worldwide. The global impact of nutrition on disease burden is a critical public health issue that touches every country on Earth.

Quick Summary

This article explores the direct and indirect links between nutritional factors and leading causes of death, examining the mechanisms by which diet contributes to cardiovascular disease, cancer, diabetes, and infectious diseases. It details how both undernutrition and overnutrition can impair health and shorten life expectancy. The content covers specific dietary components and patterns that influence disease risk and outcomes.

Key Points

Cardiovascular Disease: High sodium, saturated fats, and low fiber intake are major dietary risk factors for heart disease and stroke by contributing to high blood pressure and cholesterol.
Cancer: Obesity, high red and processed meat consumption, and low fiber intake are linked to an increased risk for several types of cancer through mechanisms like chronic inflammation and metabolic changes.
Diabetes and Liver Disease: Diets high in sugar, refined carbohydrates, and excess calories drive insulin resistance and obesity, leading to Type 2 Diabetes and Non-Alcoholic Fatty Liver Disease.
Infectious Diseases: Protein-energy malnutrition and micronutrient deficiencies cripple the immune system, leaving individuals, especially children, highly vulnerable to and more likely to die from infections.
Maternal and Neonatal Health: Maternal malnutrition significantly increases the risk of adverse pregnancy outcomes, including low birth weight and infant mortality, which are major causes of neonatal death.
Obesity: Carrying excessive body fat is an underlying risk factor that indirectly contributes to numerous leading causes of death, including CVD, certain cancers, and diabetes.
Dietary Extremes: Both chronic overconsumption of unhealthy foods (overnutrition) and severe deficiency (undernutrition) lead to pathological states that increase mortality risk through distinct biological pathways.

The Overarching Link Between Diet and Mortality

Diet is a pivotal determinant of human health, influencing both immediate well-being and long-term disease risk. The World Health Organization defines malnutrition in all its forms—including undernutrition, micronutrient deficiencies, and overweight and obesity—which together drive a significant portion of global morbidity and mortality. Poor nutrition is a contributing factor to many noncommunicable diseases (NCDs), and studies have shown that it was a major factor in a significant percentage of all deaths in 2021. This relationship is not one-dimensional but rather a complex interplay of nutrient intake, body weight, and systemic physiological processes.

Cardiovascular Disease: A Leading Cause Driven by Diet

Cardiovascular disease (CVD), encompassing conditions such as heart disease and stroke, remains the leading cause of death globally. Diet is a primary, modifiable risk factor. Unhealthy eating patterns characterized by high intake of saturated fats, trans fats, sodium, and added sugars, and low intake of fruits, vegetables, and whole grains, contribute directly to several risk factors for CVD, including high blood pressure, high cholesterol, and obesity.

High Sodium Intake: Excessive sodium intake is the single most impactful dietary risk factor globally, primarily due to its link with high blood pressure, a major cause of stroke and heart disease.
Unhealthy Fats: Diets rich in saturated and trans fats raise levels of low-density lipoprotein (LDL), or "bad" cholesterol, which can lead to plaque buildup in arteries (atherosclerosis). This plaque can restrict blood flow, leading to heart attacks and strokes.
Low Intake of Protective Foods: Conversely, insufficient consumption of fruits, vegetables, and whole grains deprives the body of fiber, potassium, and antioxidants, all of which are protective against CVD.

Cancer: Modifiable Risk and Nutritional Factors

While genetics play a role in cancer, lifestyle factors like diet are increasingly recognized as crucial influencers of risk. Nutritional habits impact cellular processes, inflammation, and hormone levels, which can either promote or inhibit cancer development.

Processed and Red Meats: The World Cancer Research Fund confirms that consuming processed meat increases the risk of bowel cancer, and high consumption of red meat is also a risk factor. These meats often contain carcinogenic compounds.
Excess Weight: Obesity is a major risk factor for several cancers, including breast, colorectal, and endometrial cancers. Excess body fat promotes a state of chronic inflammation and alters hormone levels, creating an environment favorable for cancer growth.
Dietary Fiber: A high-fiber diet is consistently linked to a lower risk of several cancers, particularly colorectal cancer. Fiber promotes digestive health and helps manage inflammation and blood sugar levels.

Diabetes and Liver Disease: The Metabolic Consequences of Poor Nutrition

Dietary habits are fundamentally linked to metabolic disorders, especially type 2 diabetes mellitus (T2DM) and non-alcoholic fatty liver disease (NAFLD). Both diseases can lead to life-threatening complications.

Type 2 Diabetes: Unhealthy diets high in simple sugars and processed carbohydrates contribute to insulin resistance and obesity, which are precursors to T2DM. Poorly managed T2DM is a significant cause of death, often due to associated cardiovascular complications.
NAFLD: This condition arises when excess fat accumulates in the liver, often due to being overweight or consuming a diet high in sweets and simple carbohydrates. NAFLD can progress to more severe conditions like cirrhosis and liver failure, which are significant causes of death. Adopting a Mediterranean diet, rich in healthy fats and low in processed foods, can help manage and reverse NAFLD.

Undernutrition and Infectious Diseases

While overnutrition drives most NCD-related deaths, undernutrition remains a grave cause of mortality, particularly in low- and middle-income countries. A compromised immune system is the central mechanism linking undernutrition to infectious diseases.

Weakened Immunity: A lack of sufficient calories, protein, and essential micronutrients like vitamins A and D, iron, and zinc severely impairs the body's immune response.
Vicious Cycle: This weakened state increases susceptibility to infections like pneumonia, measles, and diarrhea, which in turn worsen malnutrition due to appetite loss and nutrient malabsorption.
Maternal and Child Health: Malnutrition in pregnant women leads to higher rates of maternal and neonatal mortality, often linked to low birth weight and complications exacerbated by poor nutritional status.

Comparison of Nutrition-Related Mortality Factors


Condition	Primary Nutritional Factor	Underlying Mechanism	Indirect or Direct Relation?
Cardiovascular Disease	High sodium, saturated/trans fats, low fiber	Inflammation, atherosclerosis, high blood pressure	Direct and Indirect
Cancer	Processed/red meat, high sugar, excess weight	Chronic inflammation, altered hormone levels	Indirect (via obesity, inflammation)
Type 2 Diabetes	High sugar, refined carbs, excess calories	Insulin resistance, metabolic stress	Direct (via metabolic dysregulation)
Liver Disease (NAFLD)	High simple carbs, excessive calories	Fat accumulation, inflammation, scarring (cirrhosis)	Indirect (via obesity, poor diet)
Infectious Diseases	Protein-energy malnutrition, micronutrient deficiencies	Impaired immune response	Indirect (weakens host resistance)
Stroke	High sodium, unhealthy fats	High blood pressure, atherosclerosis	Direct and Indirect

Conclusion: The Path Forward

Nutrition's profound influence on the leading causes of death is a global concern. From the metabolic dysregulation caused by excess calories to the weakened immunity resulting from undernutrition, dietary factors are woven into the fabric of human health and disease. The evidence is clear: healthier dietary patterns, such as the Mediterranean or plant-based diets, can reduce the risk of many chronic conditions, including cardiovascular disease, cancer, and diabetes. Addressing malnutrition in all its forms, whether over or under, is a powerful and necessary strategy for improving public health outcomes and extending life expectancy worldwide. For the individual, making healthier dietary choices can be one of the most effective actions taken to prevent chronic disease and premature death.

Frequently Asked Questions

Poor nutrition contributes to heart disease by promoting high blood pressure, unhealthy cholesterol levels, and inflammation through excessive intake of sodium, saturated fats, and trans fats. Inadequate intake of fruits, vegetables, and whole grains also increases risk by depriving the body of protective nutrients like fiber and antioxidants.

Yes, diet can significantly impact cancer risk. By adopting healthier eating habits, such as increasing consumption of fruits, vegetables, and whole grains while limiting red and processed meats, you can lower your risk. Maintaining a healthy body weight through balanced nutrition is also crucial for cancer prevention.

Undernutrition, a form of malnutrition, severely compromises the immune system. This weakened state leaves the body more susceptible to infections and less able to fight them off effectively. This creates a vicious cycle where infection worsens malnutrition, increasing the risk of death, especially in children.

Obesity is an indirect cause of death. It is a major risk factor that leads to other chronic, life-threatening conditions like cardiovascular disease, type 2 diabetes, and certain cancers. The excess body fat associated with obesity creates inflammation and metabolic dysregulation, which contribute to these diseases.

Studies have identified high sodium intake as one of the most impactful dietary risk factors globally due to its connection with high blood pressure. Other harmful components include saturated and trans fats, refined sugars, and processed meats, which all contribute to a heightened risk of chronic disease.

Diet influences stroke risk primarily through its effect on blood pressure and cholesterol. A high-sodium diet is a significant risk factor for high blood pressure, the leading cause of stroke. Diets high in saturated and trans fats also promote atherosclerosis, narrowing the arteries and increasing stroke risk.

Nutrition is central to liver health. An unhealthy diet, particularly one high in simple carbohydrates and excessive calories, can lead to non-alcoholic fatty liver disease (NAFLD). In advanced stages, NAFLD can lead to cirrhosis and liver failure, which are often fatal. A balanced diet, such as a Mediterranean pattern, can help manage and potentially reverse NAFLD.