Nutrition: Proteins, Fats, and Minerals

Proteins

• Proteins are essential for various bodily functions: cell structure, hemoglobin formation for oxygen transport, enzyme activity, DNA and RNA synthesis, and energy production.
• The human body cannot synthesize 8 essential amino acids: lysine, tryptophan, methionine, leucine, isoleucine, phenylalanine, valine, and threonine.
• Foods high in biological value include: eggs, milk, soybeans, meats, vegetables, and grains.

Fats

• Fats are concentrated energy sources, providing twice the energy per weight compared to carbohydrates or proteins.
• Functions of fats: cell structure formation, protective cushioning and insulation around vital organs, fat-soluble vitamin absorption, and energy storage.
• Essential fatty acids are unsaturated fatty acids including linoleic, linolenic, and arachidonic acids, required for diet.
• Saturated fats and cholesterol are linked to atherosclerosis and heart disease.

Minerals

• Minerals do not contribute directly to energy but are crucial body regulators involved in metabolic pathways.
• The human body contains more than 25 essential elements.
• Important minerals include: calcium, phosphorus, iron, sodium, potassium, chloride ions, copper, cobalt, manganese, zinc, magnesium, fluorine, and iodine.

Vitamins

• Vitamins are essential organic compounds that the body cannot synthesize and must be obtained through the diet.
• Vitamins crucial to metabolism include: Vitamin A, B2 (riboflavin), niacin or nicotinic acid, and pantothenic acid.

Metabolic Pathways

• Metabolic pathways are series of chemical reactions that transform nutrients into other substances, facilitated by enzymes.
• Enzymes are vital for metabolism, enabling efficient reactions by acting as catalysts.
• Enzymes also regulate metabolic pathways in response to environmental changes or signals from other cells.

Physiologic Value of Food

• Food comprises solid and liquid materials consumed for maintaining and building body tissues, regulating processes, and producing heat for sustaining life.
• Food consists of organic (proteins, lipids, carbohydrates, vitamins) and inorganic compounds (water and minerals).
• Carbohydrates, proteins, and fats are essential nutrients required in larger quantities, while vitamins and minerals act as catalysts facilitating the utilization of major nutrients.

Metabolism

• Metabolism is the chemical process of transforming food into complex tissue elements and breaking down complex body substances into simpler ones, alongside heat and energy production.
• It encompasses all chemical processes in the body for sustaining life, representing the dynamic concept of change underlying life.
• Energy refers to the chemical energy stored in foodstuffs and accessed through metabolism.

Energy From Food

• The unit of energy used in nutrition is the kilogram calorie (kcal) or calorie, measuring the energy the body derives from food.
• Calories are by-products of the oxidation of carbohydrates, proteins, and fats in the body.

Basal Metabolic Rate (BMR)

• BMR represents the minimum amount of energy the body needs at rest to maintain vital functions.
• Factors influencing BMR: age, sex, body surface area, body composition, state of nutrition, sleep, endocrine glands, and fever.

Desirable Body Weight (DBW)

• DBW is the ideal weight for an individual based on height and age.
• Methods for calculating DBW: Ador Dionisio's Method and Tannhauser's Method.

Physical Activity

• Calorie requirements are influenced by the type and intensity of physical activity.
• Increased physical activity leads to higher calorie expenditure.

Specific Dynamic Action of Food (SDA)

• SDA refers to the energy needed to digest, transport, and utilize food.
• Carbohydrates and fats increase heat production by approximately 5% of the total calories consumed.

Daily Energy Requirement

• Daily energy requirement is estimated by adding the energy needs for basal metabolism, physical activity, and SDA.
• Steps for calculating daily energy requirement: determine DBW, calculate basal needs, adjust for sleep, add activity increment, add SDA, and sum all values.

Fluid Requirement

• The recommended fluid intake is based on caloric expenditure using the Holliday-Segar Method.

Abnormal Water Balance

Overhydration or Water Intoxication

• Occurs when excessive water intake dilutes tissues and cells, leading to potential complications like muscle cramps, weakness, low blood pressure, vomiting, convulsions, coma, and death.

Dehydration

• Occurs when water loss exceeds intake, leading to electrolyte loss, skin inelasticity, and potential complications ranging from serious to fatal.

Test your knowledge on essential nutrients including proteins, fats, and minerals. This quiz covers their roles in the body, sources, and importance in a healthy diet. Perfect for students studying nutrition and health sciences.