Double Burden of Malnutrition

The "Double Burden of Malnutrition" refers to the coexistence of undernutrition along with overweight and obesity, or diet-related non-communicable diseases (NCDs), within individuals, households, and populations throughout life.

• Broad Definition: Malnutrition is a general term encompassing both undernutrition (resulting from inadequate consumption, poor absorption, or excessive loss of nutrients) and overnutrition (resulting from excessive intake of specific nutrients).
• The Paradox: It represents a paradox where undernutrition (wasting, stunting, micronutrient deficiencies) and obesity coexist. This phenomenon is increasingly observed in developing countries like India due to nutritional and epidemiological transitions.
• Levels of Manifestation:
  • Individual Level: A person can be simultaneously stunted (chronic undernutrition) and overweight/obese. Additionally, an individual might manifest undernutrition early in life (e.g., Low Birth Weight) and develop obesity and metabolic syndrome later in life.
  • Household Level: A single household may contain an undernourished child (e.g., underweight or stunted) and an overweight or obese adult (usually the mother). Underweight and overweight often occur in the same communities and even the same households.
  • Population Level: A country or region faces a high prevalence of undernutrition alongside a rising prevalence of obesity and non-communicable diseases (NCDs).

Epidemiology

The epidemiology of DBM reflects the complex interplay between poverty, economic growth, and lifestyle changes.

Global Scenario

• Prevalence: Globally, alongside the millions who are underfed, there are billions who are overweight or obese, reflecting global inequalities. In 2020, the FAO estimated huge disparities with approximately 768 million people undernourished alongside 1.9 billion overweight or obese adults.
• Nutrition Transition: Many developing countries have transitioned from traditional diets to "Western" diets characterized by high energy density, refined grains, and highly processed foods. This transition is associated with a decrease in communicable diseases but a sharp increase in NCDs like type 2 diabetes and cardiovascular disease.

Indian Scenario

India faces a unique challenge described as "The Development Paradox," where economic growth has not sufficiently eliminated child undernutrition, yet has introduced risks of overnutrition.

• Undernutrition Statistics (NFHS-5, 2019-21):
  • 32% of children under five are underweight.
  • 36% are stunted (chronic malnutrition).
  • 19% are wasted (acute malnutrition).
  • 67% of children between 6 months and 5 years are anemic.
• Overnutrition Statistics:
  • There is a steep increase in overweight and obesity among children and adolescents.
  • Among children aged 5–9 years, approximately 4% are overweight or obese.
  • In the 10–19 years age group, the prevalence is 5%.
  • Nearly 50–80% of obese children become obese adults.
• The "Asian Paradox": South Asian populations have a specific phenotype characterized by higher fat mass and more centrally distributed fat (abdominal obesity) compared to white Caucasians of similar Body Mass Index (BMI). This puts them at higher risk for obesity-associated diseases at lower BMI thresholds.

Etiopathogenesis: The Link Between Undernutrition and Overnutrition

The DBM is biologically linked through the concept of "Fetal Programming" or the "Barker Hypothesis."

• Fetal Origins of Adult Disease (FOAD):
  • Maternal malnutrition leads to fetal malnutrition, resulting in Intrauterine Growth Retardation (IUGR) or Low Birth Weight (LBW).
  • Thrifty Phenotype: The undernourished fetus develops metabolic adaptations to survive starvation (e.g., insulin resistance, downregulated growth). These adaptations "program" the body to conserve energy.
  • The Mismatch: When these "thrifty" individuals are exposed to an environment of plenty (energy-dense foods, physical inactivity) postnatally, they are maladapted. This leads to rapid weight gain and a high risk of early-onset adult diseases like type 2 diabetes, hypertension, and coronary heart disease.
• Catch-up Growth: Rapid "catch-up" growth in weight during early childhood (crossing centiles upwards), particularly in children born LBW, is a significant risk factor for developing central obesity and metabolic syndrome in adulthood.
• Adiposity Rebound: Early adiposity rebound (the point where BMI begins to rise after its nadir in childhood, typically around 5.5 years) is associated with adult obesity. Malnutrition in early life followed by attempts to augment growth can result in undue fatness.

Drivers of the Double Burden

• Obesogenic Environment: Urbanization and the food industry have led to the availability of affordable, high-fat, high-sugar "junk food" and calorie-dense beverages. This "fast food and cola culture" contributes significantly to the rising obesity rates.
• Sedentary Lifestyle: Increased screen time (TV, mobile, computers) and reduced outdoor physical activity contribute to the energy imbalance.
• Socio-economic Factors: Poverty remains a driver for undernutrition, while increasing purchasing power without adequate nutrition knowledge leads to the consumption of prestige foods that are often nutritionally poor but calorie-rich.