Nutrition and Protein Quiz

PM906: Public Health - Lecture 7

• Course Outline: Public Health can be summarized as the "health of people" with aspects such as communicable diseases, non-communicable diseases, prevention, intervention, control and eradication, nutrition, food (quality), water, waste and wellness.
• Public Health encompasses different areas: Public, community, population; Family (maternal and child); School; Workplace (occupational); Hospital (nosocomial); and Environment (environmental).
• Nutrition: Good nutrition is fundamental for health, but malnutrition is widespread globally. Population growth and agricultural advancements can help alleviate this issue.
• 50 nutrients are crucial; deficiencies cause noticeable health issues, which are resolved by supplying the missing element.
• Energy needs are met through food intake, supporting bodily functions, physical activity, growth, tissue repair, and maintaining a 37°C body temperature.
• Energy is derived from the oxidation of carbohydrates, fats, and proteins.

Required Nutrients

• Essential amino acids, essential fatty acids, water-soluble and fat-soluble vitamins, minerals, carbohydrates/fats (energy substrate), indigestible fibers, and adequate water are required nutrients.
• Excessive nutrient intake is detrimental; intake levels should be adjusted to individual needs and vary daily.
• Undernutrition arises from an imbalanced diet, leading to deficiencies in calories and energy.

The Six Classes of Nutrients

• Macronutrients: Carbohydrates, Lipids, Proteins, and Water
• Micronutrients: Vitamins and Minerals

Food Guide Pyramid

• The Food Guide Pyramid is a graphic representation of recommended food groups and serving sizes.
• Different food groups (i.e., fats, oils, and sweets; Milk, Yogurt, & Cheese; Vegetables; Meat, Poultry, Fish, Dry Beans, Eggs, & Nuts; Fruits; Bread, Cereal, Rice, & Pasta) have recommended daily servings.

Proteins

• A protein is a complex organic nitrogenous compound composed of amino acids.
• Animal proteins (high biological value [HBV]) include meat, white meat like fish or poultry, red meat, eggs, and milk products like cheese.
• HBV protein contains nine essential amino acids imperative for developing children and adults and animals.
• Plant proteins (low biological value [LBV]) are present in pulses, grains, cereals and nuts.
• Examples of essential proteins include leucine, isoleucine, methionine, threonine, valine, phenylalanine, tryptophan, lysine, and histidine.
• Egg protein is a reference protein owing to its well-balanced amino acid composition, easy digestibility, and suitability for human metabolism.
• Plant-based proteins lacking particular amino acids can be compensated for by combining different plant protein sources in a meal.

Biological Value of Proteins

• Proteins support body building, tissue repair, enzyme and hormone production, and fluid balance.
• Proteins contribute to approximately 10% of daily caloric needs and offer supporting function in organs and tissues.

Deficiency Manifestations

• Adults: Hypoproteinemia leads to weight loss, increased susceptibility to diseases, and edema. Marasmus results from inadequate food intake.
• Infants and preschool children (PEM): Protein deficiency, particularly kwashiorkor, causes edema, including moon face edema and anemia due to low protein diet.

Carbohydrates (CHO)

• CHOs are composed of carbon, hydrogen, and oxygen.
• Animal sources: Lactose (milk sugar) and glycogen (animal starch).
• Plant sources: Simple sugars (e.g., glucose, fructose), complex sugars (e.g., starch, polysaccharides). Cellulose (dietary fiber) is non-digestible and provides bulk.

Biological Role of Carbohydrates (CHO)

• CHOs are the primary and cheapest energy source, making up more than 60% of a balanced diet.
• Inadequate CHO can lead to fat oxidation and ketone body formation. Excessive CHO consumption can contribute to obesity, heart disease, and high blood lipids.
• Dietary fiber creates a filling effect in the stomach, aiding weight management and lessening digestive issues.

Fats or Lipids

• Fats are critical for energy production, vitamin absorption (A, D, E, and K), and skin health (in children).
• Animal sources: Milk products, egg yolks, and fatty meats.
• Plant-based sources: Sesame, olive, peanut, soybean, cottonseed, palm, and sunflower oils.
• Some fats like margarine are created through vegetable oil hydrogenation, leading to saturated fats.

Dietary Fat-Associated Disorders

• Excessive fat intake contributes to obesity.
• High cholesterol levels from animal products can cause heart disease.
• Saturated fats and margarine can negatively impact lipid profiles (LDL, VLDL, HDL) contributing to heart disease and high blood pressure.

Vitamins

• Vitamins are organic compounds needed in small amounts.
• Most of them are absorbed from foods because the body cannot synthesize them on its own.

Deficiency Manifestations (Vitamins)

• Pernicious anemia (Vitamin B12 deficiency) is more likely in vegetarians, pregnant women, and those with digestive problems.
• Vitamin C deficiency (scurvy) occurs from diets lacking fresh produce.

Minerals

• Minerals are inorganic elements vital for various body functions (e.g., blood formation, bone and teeth health, osmotic pressure).
• Vulnerable groups (neonates, infants, pregnant women, elderly) are at a higher risk of mineral deficiencies (e.g., iron, calcium, iodine).
• Iodine deficiency is prevalent in areas with low dietary iodine content, potentially causing goiter (swelling of the thyroid).
• Fluorine deficiency can result in tooth fragility.

Food Microbiology

• Microorganisms require food to either spoil or improve it (fermentation).
• Foodborne illnesses can arise from microbial contamination.
• Microbial contamination of food sources can lead to toxins within the food, thus causing illness.
• Examples of foodborne illness include staphylococcal food poisoning, botulism, and salmonellosis.

Milk Microbiology

• Milkborne diseases can originate from animals (zoonotic: tuberculosis, brucellosis, etc.) or humans (e.g., typhoid, diphtheria).
• Milk treatment methods (boiling, pasteurization, and sterilization) significantly reduce microbial contamination.
• Milk quality assessment tests (e.g., methylene blue reduction, phosphatase, turbidity) identify microbial load and pasteurization effectiveness.