Human Nutrition Lecture Notes PDF 2024/2025

BINGHAM UNIVERSITY KARU COLLEGE OF MEDICINE FACULTY OF CLINICAL SCIENCES DEPARTMENT OF COMMUNITY MEDICINE AND PRIMARY HEALTH CARE LECTURE NOTE ON PHE 411 HUMAN NUTRITION BY MS DANIEL ABIGAIL ABI 2024/2025 SESSION...

BINGHAM UNIVERSITY KARU COLLEGE OF MEDICINE FACULTY OF CLINICAL SCIENCES DEPARTMENT OF COMMUNITY MEDICINE AND PRIMARY HEALTH CARE LECTURE NOTE ON PHE 411 HUMAN NUTRITION BY MS DANIEL ABIGAIL ABI 2024/2025 SESSION 1 Course Contents 1. Introduction to Nutrition 2. Classification of Food 3. Food Security and Safety 4. Cultural and Environmental Factors in Food and Nutrition 5. Nutrition and Infection 6. Malnutrition and Undernutrition 7. Socio-economic Aspects of Food 8. Problems od Overnutrition and Disease of the Affluence 9. Health Policies/Principles on Food Choices, Diets in Health and Disease 10. International/National Food and Nutrition Policies and Programs 11. Public Health Nutrition Education Plans and Strategies 12. Conduct Field Nutrition Surveys 2 Introduction Nutrition is the science that studies how the body uses nutrients from food for growth, maintenance, and optimal functioning. It explores the role of nutrients, such as carbohydrates, proteins, fats, vitamins, minerals, and water, which are essential for sustaining life and health. Proper nutrition supports physical and mental well-being, disease prevention, and longevity by providing the energy and building blocks our bodies need. This field also examines how diet impacts metabolism, cellular processes, and overall health, offering insights into dietary practices that promote wellness. The study of nutrition spans several areas, including macronutrient and micronutrient balance, dietary needs across different life stages, and the impact of lifestyle factors and socioeconomic conditions on food choices. Additionally, nutrition research emphasizes the relationship between diet and chronic diseases like obesity, diabetes, cardiovascular disease, and certain cancers. Ultimately, nutrition science seeks to guide individuals and communities toward healthier eating patterns to improve quality of life and prevent diet-related health issues. 3 1.0 Classification of Foods The classification of food is essential for nutrition science, culinary arts, agriculture, and food policy. It enables us to organize and understand the vast array of edible items that make up our diet, categorizing them based on characteristics such as nutritional content, origin, preparation method, or intended use. 1.1 Food Classification Based on Nutritional Composition One of the most common ways to classify food is by its nutrient composition. This is often used by dietitians, nutritionists, and healthcare providers to design balanced diets and guide public health nutrition policies. a) Macronutrients: Carbohydrates, Proteins, and Fats Carbohydrates are energy-providing foods typically found in grains, fruits, and vegetables. They can be further classified into simple carbohydrates (sugars) and complex carbohydrates (starches and fiber). Proteins are primarily sourced from animal products like meat, eggs, and dairy, as well as from plant-based sources such as beans, lentils, and nuts. Proteins are essential for body repair and growth. Fats include saturated, unsaturated, and trans fats, each playing unique roles in energy provision and cell structure. Sources include oils, dairy products, nuts, and fatty fish. b) Micronutrients: Vitamins and Minerals 4 Micronutrient-rich foods include vegetables, fruits, and some animal products that provide essential vitamins and minerals. These are often classified by the specific nutrients they contain: Vitamin A-rich foods include carrots, sweet potatoes, and leafy greens. Iron-rich foods include red meat, spinach, and fortified cereals. Calcium-rich foods include dairy products, broccoli, and fortified plant-based milkry. These categories help in planning nutrient-dense diets and understanding the impact of each food type on human health. 1.2 Food Classification Based on Food Groups The food group classification system is widely used for dietary guidelines and educational purposes. This classification generally includes groups such as: Fruits and Vegetables: High in fiber, vitamins, and antioxidants, they form the foundation of many dietary guidelines for their protective roles against chronic diseases. Grains: These include whole grains such as oats and refined grains such as white bread. Whole grains are preferred for their higher fiber content and lower impact on blood sugar. Proteins: Often divided into animal-based proteins (meat, fish, eggs) and plant-based proteins (beans, legumes, nuts). Plant-based diets have been associated with reduced risk of cardiovascular diseases. Dairy: Includes milk, yogurt, and cheese. These foods are rich in calcium and vitamin D, supporting bone health. Fats and Oils: Classified based on their fat content and health effects, with an emphasis on unsaturated fats, which can reduce the risk of heart disease. 5 1.3 Food Classification Based on Processing The NOVA classification system, developed by researchers at the University of São Paulo, categorizes food based on the extent and purpose of processing. This system has gained popularity due to its emphasis on health implications related to food processing. a) Unprocessed and Minimally Processed Foods Unprocessed foods are natural foods like fruits, vegetables, seeds, and meats. Minimally processed foods undergo basic processes like washing, cutting, and packaging but retain their natural state and nutrients. b) Processed Culinary Ingredients These include items used for cooking, such as oils, fats, sugar, and salt, which undergo moderate processing (e.g., pressing, refining) to obtain a usable product. These ingredients are typically added to foods to enhance flavour or cooking efficiency. c) Processed Foods Processed foods are those transformed by salting, pickling, curing, or other methods to extend shelf life or improve taste. Examples include canned vegetables, cheese, and freshly baked bread. They contain added salt, sugar, or fat and are often nutrient-dense but should be consumed in moderation. d) Ultra-Processed Foods Ultra-processed foods (UPFs) are industrial formulations made primarily from processed ingredients, with minimal whole food content. Examples include soft drinks, chips, and many packaged snacks. Studies suggest that high UPF consumption may lead to negative health outcomes, including obesity and metabolic disorders (Fardet, 2018). 6 1.4 Food Classification Based on Biological Source Another classification method is based on the biological source or origin of the food: Plant-based foods: This includes all foods derived from plants, such as fruits, vegetables, legumes, grains, seeds, and nuts. Plant-based diets have been linked to numerous health benefits, including reduced risks of heart disease, cancer, and diabetes. Animal-based foods: This category includes meat, fish, dairy, and eggs. Animal-based foods are high in essential nutrients, particularly protein, iron, and vitamin B12, but should be consumed in balance due to associations with certain health risks when consumed excessively. 1.5 Functional Classification of Foods Functional foods are categorized based on their health-promoting properties, and they include: Probiotic Foods: Foods containing live bacteria beneficial for gut health, such as yogurt, kimchi, and kombucha. Fortified and Enriched Foods: These are foods with added nutrients, like vitamin D- fortified milk or iron-enriched cereals. Bioactive Compounds: Some foods, like tomatoes, blueberries, and green tea, are high in antioxidants and polyphenols, which are believed to help reduce oxidative stress and inflammation. 1.6 Traditional vs. Modern Foods 7 In certain cultural contexts, foods are also classified as traditional (locally sourced and prepared using traditional methods) versus modern (often industrially processed). Traditional foods, which are more common in Indigenous diets, are often celebrated for their nutrient density and cultural significance. For instance, traditional foods in many Native American diets include bison, wild rice, and corn, while the Mediterranean diet emphasizes traditional foods like olive oil, fish, and legumes. 8 2.0 Food Security and Safety Food security and food safety are critical and interrelated issues in the context of global development, health, and sustainability. They affect economic stability, public health, and overall quality of life. Understanding these two pillars is essential in the journey toward achieving a world free from hunger and malnutrition. 2.1 Food Security Food security exists when all people, always, have physical, social, and economic access to sufficient, safe, and nutritious food to meet their dietary needs and food preferences for an active and healthy life (FAO, 1996). Food security has four main pillars: 1. Availability - This is influenced by the production, distribution, and trade of food products. Enough food should be available for all individuals in a society. 2. Accessibility - Economic and physical accessibility ensures that people can afford and physically access food. 3. Utilization - The proper utilization of food depends on proper dietary choices, food preparation, diversity in diet, and biological factors affecting how nutrients are absorbed. 4. Stability - Food security should be stable over time without risk of sudden drops due to factors like environmental disasters, economic instability, or conflict. Challenges to Food Security 9 Some of the most pressing threats to food security include climate change, population growth, political instability, and economic inequality. 1. Climate Change: Climate change is one of the biggest threats to food security, affecting crop yields, livestock productivity, and fisheries. According to IPCC reports, rising temperatures and changing precipitation patterns directly impact crop productivity and increase the frequency of extreme weather events like droughts and floods (IPCC, 2021). 2. Population Growth: The global population is projected to reach nearly 10 billion by 2050 (UN, 2022), placing unprecedented demand on food production systems. Increasing food production to meet this demand, especially with limited arable land and water resources, is challenging. 3. Economic Inequality: While global food production might be sufficient to feed the world’s population, economic disparities mean that millions lack the purchasing power to access nutritious food. Poverty limits people’s ability to buy food and invest in food production, perpetuating a cycle of hunger and malnutrition (World Bank, 2020). 4. Conflict and Displacement: Conflicts disrupt food production, destroy infrastructure, displace populations, and strain resources in neighbouring regions. For instance, in 2021, around 60% of people suffering from food insecurity lived in areas affected by conflict (WFP, 2021). Addressing Food Security Policies and technological innovations are crucial for addressing food security: 10  1. Sustainable Agriculture: Practices like crop rotation, permaculture, agroforestry, and the use of organic fertilizers help maintain soil health and enhance food security. Innovations in biotechnology, such as drought-resistant crops, can also increase yields under challenging climatic conditions. 2. Food Policy and Subsidies: Governments often provide subsidies and other supports to farmers to stabilize food prices and ensure a consistent food supply. In addition, trade policies are critical for maintaining food availability across regions and countries. 3. Social Protection Programs: These programs, including food banks, school meal programs, and conditional cash transfers, directly help vulnerable populations access food (FAO, 2020). 2.2 Food Safety Definition and Importance Food safety refers to the proper handling, preparation, and storage of food to prevent foodborne illnesses. According to the WHO, unsafe food containing harmful bacteria, viruses, parasites, or chemicals is responsible for over 600 million cases of foodborne illness and 420,000 deaths each year globally (WHO, 2020). Principles of Food Safety The primary principles of food safety focus on preventing contamination and ensuring that food products are safe for consumption. These include: 1. Hazard Analysis and Critical Control Points (HACCP): HACCP is a systematic preventive approach to food safety that identifies critical points where potential hazards could occur in the production process and sets controls to prevent or eliminate them. 11  2. Food Safety Regulations: Governments and international bodies such as the Codex Alimentarius Commission, established by the FAO and WHO, provide standards, guidelines, and codes of practice to ensure food safety across countries. 3. Foodborne Illnesses: Common pathogens like Salmonella, E. coli, and Listeria are responsible for significant foodborne illnesses. Contamination may occur at any stage from production to consumption, and ensuring safety requires stringent hygiene practices and regulations. 4. Proper Storage and Handling: Storage conditions like temperature control, safe packaging, and sanitation play a crucial role in food safety. Incorrect storage, especially of perishable items, promotes bacterial growth, which can lead to foodborne illnesses. Challenges in Food Safety 1. Globalization of Food Supply Chains: Global trade in food products increases the complexity of food safety oversight. Foods are now processed, packaged, and transported across international borders, increasing the potential for contamination. Ensuring safety across such extensive supply chains requires international collaboration and consistent standards (FAO, 2018). 2. Antibiotic Resistance: The overuse of antibiotics in food animals is contributing to antibiotic resistance in humans. This issue has been flagged by WHO as a significant threat to global health (WHO, 2021). 3. Consumer Misinformation and Trends: With the rise of organic, raw, and other alternative diets, misinformation about food safety has increased. Certain food practices, such as consuming unpasteurized dairy products or improperly cooked meats, can increase the risk of foodborne illness. 12 Technological Advances in Food Safety 1. Blockchain Technology: Blockchain technology in food traceability helps monitor each stage of the food supply chain, making it easier to trace sources of contamination quickly. 2. Rapid Pathogen Detection: Advanced detection methods like PCR (Polymerase Chain Reaction) and biosensors enable faster identification of pathogens, reducing the risk of widespread contamination. 3. Food Irradiation: Used in many countries, food irradiation can eliminate harmful bacteria and pathogens, increasing the shelf life of foods like fruits, vegetables, and meats. However, concerns around nutrient loss and consumer acceptance remain (FDA, 2022). 1.3 Interconnection Between Food Security and Food Safety Food security and food safety intersect closely, as ensuring food is available but unsafe can be detrimental to public health. Unsafe food also affects food utilization, which is a key aspect of food security. For example, in areas with high food insecurity, foodborne illnesses can exacerbate malnutrition by impairing nutrient absorption. Furthermore, investments in food safety infrastructure (like clean water, hygiene, and storage) contribute to both food security and public health. References 1. FAO. (1996). Rome Declaration on World Food Security and World Food Summit Plan of Action. FAO. 2. IPCC. (2021). Climate Change 2021: The Physical Science Basis. Cambridge University Press. 13 3. World Bank. (2020). Poverty and Shared Prosperity 2020. World Bank. 4. WHO. (2020). Food Safety: Key Facts. World Health Organization. 5. WFP. (2021). Global Report on Food Crises 2021. World Food Programme. 6. FAO. (2018). Trade and Food Security. FAO. 7. WHO. (2021). Antibiotic Resistance. World Health Organization. 8. FDA. (2022). Food Irradiation: What You Need to Know. 14 3.0 Cultural and Environmental Factors in Food and Nutrition 3.1 Cultural Factors in Food and Nutrition Cultural factors refer to the customs, traditions, and values that shape a society's relationship with food and nutrition. Cultural Food Practices 1. Meal Patterns and Timing: Different cultures have varying meal patterns and timing, such as the emphasis on breakfast in Western cultures or the importance of dinner in many Asian cultures. 2. Food Preparation and Cooking Methods: Cultural food practices often involve specific preparation and cooking methods, such as grilling in many African cultures. 3. Food Sharing and Commensality: In many cultures, sharing food is an important aspect of social bonding and community building. 4. Dietary Restrictions and Taboos: Certain cultures have dietary restrictions or taboos, such as avoiding pork in Islamic and Jewish cultures or refraining from beef in Hindu culture. Implications for Nutrition and Health 1. Nutrition-Related Health Disparities: Cultural factors can contribute to nutrition- related health disparities, particularly among marginalized or minority populations. 15  2. Culturally Sensitive Nutrition Education: Nutrition education programs should be tailored to the cultural needs and preferences of the target population. 3. Food Security and Access: Cultural factors can influence food security and access, particularly in communities with limited access to culturally acceptable food options. 3.2 Environmental Factors in Food and Nutrition Environmental factors in food and nutrition refer to the external influences that affect the production, processing, distribution, preparation, and consumption of food. These factors can impact the quality, safety, and availability of food, ultimately affecting human nutrition and health. Some examples of environmental factors in food and nutrition include: 1. Climate and weather: Climate change, droughts, floods, and other weather events can impact crop yields, food availability, and nutritional quality. 2. Soil and water quality: Soil degradation, water pollution, and poor irrigation practices can affect crop nutrition and food safety. 3. Air pollution: Air pollution can contaminate food crops and affect nutritional quality. 4. Food processing and storage: Improper food processing, storage, and handling can lead to food spoilage, contamination, and nutrient loss. 5. Food distribution and access: Food distribution networks, transportation, and storage can impact food availability, affordability, and nutritional quality. 6. Cultural and socioeconomic factors: Cultural preferences, socioeconomic status, and education can influence food choices, dietary habits, and nutritional outcomes. 7. Agricultural practices: Farming practices, such as organic vs. conventional farming, can impact food nutritional quality and environmental sustainability. 16  8. Food policy and regulations: Government policies, regulations, and subsidies can influence food production, processing, and consumption patterns. 9. Urbanization and lifestyle: Urbanization, sedentary lifestyles, and changing work patterns can affect dietary habits and nutritional outcomes. These environmental factors can have significant impacts on food and nutrition, including: - Food insecurity and malnutrition - Nutrient deficiencies and excesses - Foodborne illnesses and diseases - Environmental degradation and sustainability 17 4.0 Nutrition and Infection The interplay between nutrition and infection is fundamental in both individual health and public health contexts. Nutrition influences immune function, susceptibility to infections, disease severity, and recovery outcomes. In turn, infections can impair nutrient absorption, leading to malnutrition and complicating recovery. 1. Nutrition and Immune System Function Nutrients are critical in maintaining immune system function. Deficiencies in specific vitamins, minerals, and macronutrients weaken immune responses, increasing susceptibility to infections. Key nutrients that influence immunity include: i. Proteins: Essential for antibody production and cell repair, proteins are building blocks of immune cells. Low protein intake can impair the body’s ability to produce antibodies, increasing susceptibility to infections. Vitamins: Vitamin A supports skin and mucosal health, essential barriers against pathogens. Its deficiency is associated with an increased risk of respiratory and diarrheal infections, especially in children. 18  Vitamin C is a potent antioxidant that neutralizes free radicals, protecting immune cells from damage. It also enhances the activity of immune cells like neutrophils and T-cells. Vitamin D has immunomodulatory effects, enhancing pathogen-killing abilities of macrophages. Vitamin D deficiency has been linked with an increased risk of respiratory infections. ii. Minerals: Zinc supports immune cell development and function, particularly in T-cell and B-cell activity. Zinc deficiency has been associated with impaired immune function, delayed wound healing, and a higher risk of infections. Iron plays a crucial role in cellular respiration and DNA synthesis. Iron deficiency can impair the immune response, but excessive iron can promote pathogen growth, so maintaining balance is essential. 2. Malnutrition and Increased Susceptibility to Infection Malnutrition, particularly protein-energy malnutrition, is a leading factor contributing to immunodeficiency worldwide. Malnutrition leads to weakened physical barriers like the skin and mucous membranes and reduces the function of immune cells, including phagocytes, lymphocytes, and cytokines. In children, malnutrition is strongly associated with higher rates of mortality due to common infections, particularly in low-income regions. i. Protein-energy malnutrition affects the thymus and other lymphoid tissues, impairing the production of T-lymphocytes and reducing antibody production, which diminishes the body’s ability to fight infections such as measles and tuberculosis. 19  ii. Micronutrient deficiencies in vitamin A, and zinc have been linked with weakened immune defences, leading to increased mortality in malnourished populations when exposed to infectious diseases. In areas with high infection rates and limited resources, infections exacerbate malnutrition by increasing metabolic demands and reducing appetite, setting off a vicious cycle. A well- documented example is in regions affected by HIV/AIDS, where malnutrition worsens the severity of the disease, while the infection impairs nutrient absorption. 3. Impact of Infection on Nutrient Absorption and Metabolism Infections place significant strain on the body’s metabolic and nutritional status. For example: i. Gastrointestinal infections: Pathogens like Escherichia coli or Shigella lead to diarrhea and vomiting, causing nutrient loss and dehydration, both of which impair recovery and immunity. ii. Fever and inflammation: In response to infection, the body’s metabolic rate increases, leading to higher nutrient requirements, especially for protein and calories. Fever increases the rate of metabolism, causing a loss of muscle mass and diminished nutrient stores, which are vital for recovery. iii. Malabsorption and gut microbiota: Many infections disturb the gut microbiota, which is essential for nutrient absorption and immune function. Chronic infections and malnutrition are often linked with altered gut microbiota, leading to further malabsorption of nutrients and weakened immunity. 4. Nutritional Interventions to Prevent and Treat Infections Nutrition interventions play a crucial role in preventing infections and aiding recovery: 20  i. Micronutrient supplementation: Supplementing with vitamin A, zinc, and vitamin D has been effective in reducing the incidence of respiratory and diarrheal infections in children. For example, vitamin A supplementation in children is linked with reduced mortality from measles and diarrhea, especially in regions where deficiencies are common. ii. Protein-energy supplementation: In malnourished populations, protein-energy supplementation helps build lean body mass, strengthening physical and immune barriers against infection. In regions affected by food scarcity, such programs have proven essential in lowering infection rates and improving recovery outcome. iii. Nutritional support during recovery: Following an infection, dietary support that includes high-protein foods, fruits, and vegetables rich in antioxidants helps restore nutrient levels, promotes healing, and reduces the risk of secondary infections. In cases of HIV/AIDS, patients benefit from tailored nutrition plans that counteract both weight loss and nutrient depletion due to the illness. 5. The Nutrition-Infection Cycle in Vulnerable Populations Vulnerable populations, including children, the elderly, and individuals with chronic illnesses, are at a higher risk of both malnutrition and infections, creating a feedback loop: i. Children in low-income countries: Malnutrition is both a cause and consequence of infections in children. Repeated infections deplete nutrient stores and weaken immunity, making children more susceptible to subsequent infections. Improving nutrition in these populations could significantly lower mortality rates. ii. The elderly: Older adults experience natural immune decline, and their diets are often deficient in essential nutrients. This increases their susceptibility to infections like 21  pneumonia and influenza. Nutrition interventions, particularly those emphasizing protein, vitamins, and minerals, can enhance immune function in older adults. iii. Chronic illness patients: Patients with diseases such as diabetes, cancer, and HIV/AIDS experience altered nutrient absorption and utilization, often due to both the disease and medication side effects. Nutritional interventions have shown improvements in recovery rates and quality of life in such populations. 5.0 Malnutrition and Undernutrition 5.1 Introduction to Malnutrition and Undernutrition Malnutrition is a broad term that encompasses both undernutrition and overnutrition. It refers to an imbalance in a person’s intake of nutrients, which can lead to health problems. While overnutrition involves excess intake, resulting in overweight or obesity, undernutrition is defined by inadequate intake, leading to health issues associated with deficiencies. Malnutrition, particularly undernutrition, remains a global health crisis, with severe implications on individual and societal levels. According to the World Health Organization (WHO), malnutrition is responsible for nearly half of all deaths in children under five, primarily in low- and middle-income countries (World Health Organization, 2021). Undernutrition, a specific form of malnutrition, arises from a lack of essential nutrients and energy needed for normal bodily function and growth. This state is often associated with food insecurity, poor dietary diversity, and limited access to clean water and healthcare. The primary forms of undernutrition are stunting (low height for age), wasting (low weight for 22 height), underweight (low weight for age), and deficiencies in vital vitamins and minerals, often referred to as micronutrient malnutrition (UNICEF, 2019). 5.2 Types of Undernutrition a. Stunting Stunting is a severe form of chronic undernutrition that often occurs during critical periods of early childhood. It is associated with prolonged dietary inadequacy, infections, and poor socioeconomic conditions, impairing growth and cognitive development. According to UNICEF, children who suffer from stunting may face learning difficulties, reduced income potential, and increased risk of chronic diseases later in life (UNICEF, 2020). b. Wasting Wasting, or acute malnutrition, indicates severe weight loss and is usually a result of sudden food deprivation or disease. Children with wasting are at a higher risk of mortality because their immune systems are weakened, making them more susceptible to infections. Wasting is often measured through a child’s weight-for-height and is commonly seen in regions affected by acute crises such as famine, war, or natural disasters. c. Underweight Underweight reflects an individual’s weight relative to age. Underweight status is common in areas of severe food insecurity and is an indicator of both acute and chronic malnutrition. Children who are underweight may face increased morbidity and mortality risks, with long- term effects on physical and mental development (WHO, 2021). d. Micronutrient Deficiencies Micronutrient deficiencies, often termed "hidden hunger," refer to the lack of essential vitamins and minerals, such as vitamin A, iron, iodine, and zinc. Each of these nutrients plays 23 a crucial role in bodily functions, and their deficiency can lead to various health issues. For example: i. Vitamin A deficiency leads to blindness and increases the risk of disease and death from severe infections. ii. Iron deficiency is the leading cause of anaemia, which affects millions, particularly women and children, and impairs cognitive and physical development. 5.3 Causes of Malnutrition and Undernutrition The root causes of malnutrition are complex and multi-dimensional. They range from immediate factors, such as inadequate dietary intake and disease, to underlying causes like food insecurity, poor sanitation, lack of healthcare access, and social and economic inequality. a. Socioeconomic Factors Economic instability often leads to food insecurity, limiting access to nutritious food. Low- income families may rely on cheaper, calorie-dense foods that lack essential nutrients. Furthermore, systemic poverty can prevent access to healthcare, adequate sanitation, and education, all of which play critical roles in preventing malnutrition (FAO, 2021). b. Environmental and Health-Related Factors Malnutrition is exacerbated by environmental and health factors. Frequent infections, such as diarrhea or respiratory infections, can reduce nutrient absorption, aggravating undernutrition. Additionally, inadequate sanitation and hygiene contribute to disease transmission, further hindering nutrient retention and absorption. c. Inadequate Healthcare Access 24 Lack of healthcare facilities and limited maternal and child health programs can lead to undiagnosed and untreated malnutrition. In low-resource settings, children are often born with a higher risk of malnutrition due to maternal malnutrition during pregnancy, which leads to low birth weight and increased vulnerability (UNICEF, 2019). 5.4 Consequences of Undernutrition a. Impact on Physical Health and Development Undernutrition impairs physical growth and development, particularly in children. Stunting and wasting can lead to lifelong challenges, including reduced muscle mass, lower bone density, and compromised immune function. According to research, stunted children are at greater risk of chronic illnesses in adulthood, including diabetes, cardiovascular disease, and obesity, due to metabolic adaptations made during early life malnutrition. b. Cognitive Development Malnutrition has a significant impact on brain development. Micronutrient deficiencies, particularly of iron and iodine, impair cognitive function and learning ability. Studies have shown that children who experience malnutrition in the early years of life may suffer from reduced school performance, lower IQ scores, and limited work capacity later in life. c. Economic and Social Implications Malnutrition not only affects individuals but also has substantial societal and economic implications. Malnourished individuals tend to be less productive, with lower lifetime earnings. Consequently, malnutrition reduces national economic growth, particularly in countries with high rates of undernutrition. According to the World Bank, countries with high 25 rates of malnutrition may lose up to 3% of their annual GDP due to reduced productivity and increased healthcare costs (World Bank, 2018). 5.5 Addressing Malnutrition and Undernutrition: Global Interventions a. Food and Nutrition Security Programs Several international organizations, such as the WHO, UNICEF, and the Food and Agriculture Organization (FAO), implement food and nutrition security programs to address malnutrition. Programs focusing on food fortification, supplementation, and cash or food transfers aim to increase access to nutritious food among vulnerable populations (WHO, 2021). b. Improving Maternal and Child Health Maternal nutrition programs, which focus on antenatal care and breastfeeding, are crucial in preventing early-life malnutrition. The WHO recommends exclusive breastfeeding for the first six months of life, followed by the introduction of complementary foods to meet the child’s evolving nutritional needs (World Health Organization, 2021). c. Education and Awareness Education plays a critical role in malnutrition prevention. Programs educating families on dietary diversity, proper hygiene practices, and the importance of balanced nutrition contribute to long-term improvements in health outcomes. For example, community-based nutrition education programs in Kenya have led to significant reductions in childhood stunting. d. Policy and Legislation Addressing malnutrition requires policy-level interventions. Governments can play an essential role by implementing policies aimed at improving food security, sanitation, and 26 healthcare access. For instance, Ethiopia’s National Nutrition Program, which provides subsidies for fortified foods, has significantly decreased the prevalence of malnutrition (UNICEF, 2019). References  UNICEF (2019). The State of the World’s Children 2019: Children, food, and nutrition. UNICEF.  World Bank (2018). The cost of malnutrition and stunting: economic implications. World Bank.  World Health Organization (2021). Nutrition: Malnutrition. WHO. 7.0 Problems of Over Nutrition and Disease of the Affluence Over-nutrition and diseases of affluence, often associated with high-income and industrialized societies, represent a pressing global health issue. These conditions include obesity, cardiovascular diseases, type 2 diabetes, certain cancers, and other chronic illnesses driven by lifestyle and dietary factors. While many regions still face undernutrition, others—particularly in the Global North but increasingly in developing regions—suffer from the opposite: an overabundance of calories, often from highly processed foods. This 27 imbalance has led to a rise in chronic, lifestyle-related diseases that carry significant social, economic, and healthcare implications. 7.1 Understanding Over-Nutrition Over-nutrition is an excessive intake of energy or nutrients, which can lead to weight gain and the accumulation of fat in the body. The WHO defines it as a type of malnutrition that results from a higher calorie intake than the body needs, often coupled with nutrient-poor food choices, which can lead to obesity and associated health complications (WHO, 2018). In wealthy societies, access to affordable, high-calorie foods has increased, with processed foods rich in sugars, fats, and salt dominating diets. This over-nutrition is influenced by socioeconomic factors, urbanization, and lifestyle shifts that discourage physical activity. For instance, individuals with sedentary jobs, long working hours, or access to motorized transport may experience a significant drop in caloric expenditure, resulting in a positive energy balance and subsequent weight gain. 7.2 Diseases of Affluence Diseases of affluence refer to chronic, non-communicable diseases that were historically more common in wealthier populations but are now rising in prevalence worldwide. They often stem from lifestyle choices influenced by economic abundance, such as high-calorie diets, sedentary behaviour, and reliance on processed foods. Some of the primary diseases of affluence include: i. Obesity: Excess weight is the most direct consequence of over-nutrition. Obesity is a significant risk factor for several diseases, including type 2 diabetes, cardiovascular disease, and certain cancers. The prevalence of obesity has doubled since the 1980s, 28  with global estimates indicating that 39% of adults are overweight, and 13% are obese (WHO, 2021). ii. Type 2 Diabetes: Strongly associated with obesity, type 2 diabetes results from insulin resistance often caused by a high intake of sugary foods and refined carbohydrates. Countries with higher economic status see an increased prevalence of this condition as dietary patterns shift towards high-calorie, low-nutrient foods. iii. Cardiovascular Disease: Saturated and trans fats, common in processed and fried foods, elevate cholesterol levels, increasing the risk of heart disease. Heart disease is now the leading cause of death worldwide, with affluent lifestyles significantly contributing to its rise. iv. Certain Cancers: Some cancers, such as colorectal, breast, and prostate cancers, are more prevalent in affluent societies, partly due to diet, obesity, and a sedentary lifestyle. Diets high in red meat and processed foods, combined with low physical activity, are known risk factors. 7.3 Mechanisms Linking Over-Nutrition to Disease The link between over-nutrition and disease is complex, involving metabolic, hormonal, and inflammatory pathways: i. Inflammation: Over-nutrition, particularly from processed foods high in sugar and saturated fats, can lead to systemic inflammation, a known contributor to insulin resistance, atherosclerosis, and even certain cancers. ii. Insulin Resistance: Excess body fat, particularly abdominal fat, interferes with insulin’s ability to regulate blood sugar, leading to type 2 diabetes. Chronically high insulin levels, in turn, contribute to weight gain and complicate blood sugar control. 29  iii. Oxidative Stress: High-calorie, low-nutrient foods can result in oxidative stress, which damages cells and promotes aging, cancer, and cardiovascular disease. 7.4 Economic and Social Impacts Diseases of affluence impose a tremendous economic burden on healthcare systems and society at large. The cost of treating conditions like heart disease, diabetes, and cancer is high, straining public health resources. In the United States alone, obesity-related healthcare costs are estimated at around $147 billion per year. Beyond financial costs, diseases of affluence reduce quality of life, increase mortality, and disproportionately affect low-income individuals even in affluent societies due to disparities in access to healthy food and healthcare services. 7.5 Interventions and Public Health Strategies Addressing over-nutrition and related diseases requires a multi-faceted approach that includes public policy, education, and healthcare interventions. Key strategies include: i. Policy Interventions: Governments can implement policies to limit the sale of sugary drinks, subsidize healthy foods, and require clear nutritional labelling. ii. Nutritional Education: Educational campaigns that promote balanced diets, encourage cooking at home, and reduce reliance on processed foods are crucial. Public health agencies and schools can promote a greater understanding of the health impacts of food choices. iii. Urban Planning and Physical Activity Promotion: Ensuring that urban spaces have accessible parks, walking paths, and safe bike routes encourages physical activity, which is essential for energy balance and overall health. 7.6 Challenges to Addressing Over-Nutrition 30 Despite efforts to curb diseases of affluence, there are significant challenges. The marketing power of food industries often outpaces public health efforts, with billions spent on advertising unhealthy foods. Additionally, socio-economic inequalities play a role; lower- income communities in wealthy countries often have limited access to fresh produce and more exposure to fast-food outlets. 9.0 Public Health Nutrition Education Plans and Strategies Public Health Nutrition Education Plans and Strategies are essential tools in promoting healthier eating patterns, preventing nutrition-related diseases, and addressing public health challenges related to diet and nutrition. These plans involve comprehensive approaches that 31 include policymaking, community-based programs, and education campaigns. They often target vulnerable groups, including children, the elderly, and socioeconomically disadvantaged populations. 9.1 Definition and Importance of Public Health Nutrition Education Public Health Nutrition Education (PHNE) refers to a structured approach to imparting nutrition-related knowledge, skills, and behaviours to populations to prevent diseases, improve health, and enhance the quality of life. PHNE is rooted in the understanding that dietary habits are closely linked to various chronic conditions, such as obesity, diabetes, cardiovascular diseases, and some cancers. According to the WHO, unhealthy diets are a significant risk factor globally, contributing to an estimated 11 million deaths per year. Goals of PHNE 1. Promote Healthy Dietary Habits: Encourage balanced diets rich in vegetables, fruits, whole grains, lean proteins, and healthy fats. 2. Prevent Malnutrition: Address both undernutrition and overnutrition, focusing on nutrient deficiencies, especially in vulnerable populations. 3. Reduce Chronic Disease Incidence: Educate the public on the link between diet and diseases like diabetes, hypertension, and obesity. 4. Encourage Informed Decision-Making: Equip individuals with the knowledge to make healthier food choices in diverse contexts. 9.2 Framework for Nutrition Education Programs The Ecological Model is commonly used to design PHNE programs. This model suggests that individual behaviours are influenced by multiple levels: individual, interpersonal, 32 organizational, community, and policy levels. This framework guides the creation of multifaceted interventions that address various influences on dietary choices. Components of a PHNE Framework Assessment: Identifying the dietary habits, needs, and health challenges of the target population. Planning: Establishing objectives, identifying resources, and creating culturally sensitive educational materials. Implementation: Delivering educational interventions, which could include workshops, seminars, media campaigns, and school-based programs. Evaluation: Assessing the program's effectiveness in achieving its objectives through data collection and analysis. 9.3 Public Health Nutrition Education Strategies Public Health Nutrition Education encompasses several strategies tailored to meet the needs of different population groups and communities. The following strategies are widely implemented in PHNE programs: A. Community-Based Interventions Community-based programs are highly effective for public health nutrition, as they allow for interventions tailored to local needs and cultures. These programs often involve partnerships with local stakeholders, such as community centres, non-profits, and health organizations, to promote dietary change on a larger scale. Examples of Successful Community-Based Programs: 33  1. Community Kitchens: Programs like the Community Food Centres Canada (CFCC) use cooking sessions to teach participants about nutrition, while also providing social support and food access. 2. Farmers’ Markets and Community Gardens: These provide access to fresh produce and educate the public on the importance of eating locally grown fruits and vegetables. B. School-Based Nutrition Education Schools are an ideal setting for public health nutrition education, as they allow for early intervention in shaping children’s dietary habits. School-based programs often involve integrating nutrition education into the curriculum, creating school gardens, and improving the quality of school meals. Examples of School-Based Nutrition Education Programs: 1. The Food and Nutrition Education Program (FNEP) in the United States provides nutrition education to school children and their families, aiming to improve dietary habits through interactive lessons and food preparation activities. 2. Harvest of the Month Programs: These programs introduce children to new fruits and vegetables each month, often including tastings and classroom activities to increase familiarity with healthy foods. C. Policy and Advocacy 34 Policies are fundamental to creating environments that encourage healthy eating. Public health nutrition policies often focus on limiting the availability of unhealthy foods, encouraging healthy options in public institutions, and implementing food labelling regulations. Examples of Policy-Based Approaches: 1. Sugar-Sweetened Beverage Taxes: Taxes on sugary drinks are implemented in various regions, to reduce consumption and fund nutrition education programs. 2. Nutritional Labelling Requirements: Mandates for clear labelling help consumers make informed choices and are an essential tool in PHNE. 9.4 Communication and Media Strategies Media campaigns and social media have become powerful tools for promoting nutrition education. These campaigns use mass communication channels to reach diverse audiences with messages about healthy eating, often designed to resonate culturally with the target demographic. Examples of Effective Media Campaigns: 1. Social Marketing Campaigns: These campaigns have been effective in influencing people's behaviours, attitudes, and beliefs towards healthy nutrition. For instance, a social marketing campaign promoting the consumption of locally grown fruits and vegetables encouraged people to make healthier choices. 2. 5 A Day Campaign: This program, initially launched by the U.S. National Cancer Institute, aimed to increase fruit and vegetable intake. It was highly effective in increasing public awareness about the importance of a diet rich in fruits and vegetables. 35  3. Change4Life (UK): A nationwide campaign designed to encourage families to eat healthier and become more physically active, Change4Life employs social media, apps, and television advertisements to reach millions. 9.5 Monitoring and Evaluation For nutrition education programs to be effective, regular monitoring and evaluation are necessary. This process ensures that the programs meet their intended objectives and helps identify areas for improvement. Key Evaluation Methods: Pre- and Post-Intervention Surveys: Collect data on dietary habits before and after program implementation. Focus Groups and Interviews: Gather qualitative insights from participants and community stakeholders. Health Outcomes Tracking: Measure long-term health indicators, such as Body Mass Index (BMI) or rates of nutrition-related illnesses. 9.6 Challenges and Future Directions A. Challenges 1. Cultural Sensitivity: Programs need to be tailored to respect cultural food preferences and practices, which can vary significantly. 2. Funding Limitations: Sustaining long-term programs requires consistent funding, which can be challenging in low-resource settings. 3. Addressing Misinformation: Combatting nutrition misinformation spread through social media remains a critical challenge. 36 B. Future Directions The future of Public Health Nutrition Education lies in integrating technology, personalized nutrition education, and expanding community partnerships. Mobile applications, tele- nutrition, and digital media offer new opportunities to reach broader audiences with tailored messages and provide ongoing support for healthier choices. 37 Assignment 1. Write note on the socio-economic aspects of food. 2. Write note on any three (3) each of International and National Food and Nutrition Policies and Programs. (To be submitted on the 3rd of February 2025 unfailingly) 38