Chapter 1 Health and Nutrition PDF

Chapter 1 Health and Nutrition Contents 1. What is health? 2. Types of health 3. What is Nutrition? 4. What are Dietetics? 5. Dietary Requirements of Human Body 6. Nutrients 7. Functions of Nutrients 8. The Importance of Good Nutrition 9. Balanced Diet 10.Assessing the BMI 11.R...

Chapter 1 Health and Nutrition Contents 1. What is health? 2. Types of health 3. What is Nutrition? 4. What are Dietetics? 5. Dietary Requirements of Human Body 6. Nutrients 7. Functions of Nutrients 8. The Importance of Good Nutrition 9. Balanced Diet 10.Assessing the BMI 11.Recommended Dietary Allowances (RDAs) 12.Types of Malnutrition 13.Eating disorders 14.Assessment HEALTH WHO definition of health: “a state of complete physical, mental and social well- being and not merely the absence of disease or infirmity”. A healthy lifestyle provides the means to lead a full life with meaning and purpose. Healthy development of the child is of basic importance; the ability to live harmoniously in a changing total environment is essential to such development. TYPES OF HEALTH Mental and physical health is probably the two most frequently discussed types of health. Spiritual, emotional, and financial health also contributes to overall health. Medical experts have linked these to lower stress levels and improved mental and physical well-being. Physical health A person who has good physical health is likely to have bodily functions and processes working at their peak. This is not only due to an absence of disease. Regular exercise, balanced nutrition, and adequate rest all contribute to good health. People receive medical treatment to maintain the balance, when necessary. Physical well-being involves pursuing a healthful lifestyle to decrease the risk of disease. Maintaining physical fitness, for example, can protect and develop the endurance of a person’s breathing and heart function, muscular strength, flexibility, and body composition. Looking after physical health and well-being also involve reducing the risk of an injury or health issue. Good physical health can work in tandem with mental health to improve a person’s overall quality of life. Mental health Mental health refers to a person’s emotional, social, and psychological well- being. Mental health is as important as physical health as part of a full, active lifestyle. It is harder to define mental health than physical health because many psychological diagnoses depend on an individual’s perception of their experience. Good mental health is not only categorized by the absence of depression, anxiety, or another disorder. It also depends on a person’s ability to enjoy life, feel safe and secure, achieve their full potential and balance different elements of life, such as family and finances Physical and mental health has strong connections. For example, if a chronic illness affects a person’s ability to complete their regular tasks, it may lead to depression and stress. These feelings could be due to financial problems or mobility issues. A mental illness, such as depression can affect body weight and overall function. Nutrition The process of taking in food and using it for growth, metabolism, and repair. Nutritional stages are ingestion, digestion, absorption, transport, assimilation, and excretion. The saying ‘‘You are what you eat” seems to be proven true. We eat different kinds of food such as dal, chapatti, bread, rice, vegetables, milk, lassi, etc. All these different kinds of food provide us with nutrients to keep us healthy and active. It is important to know what food to eat in order to stay Healthy. The science of food and nutrients and their action on our health is called Nutrition. Nutrition and health, in fact, are two sides of the same coin. They are, therefore, inseparable. Health depends to a large extent on nutrition, and nutrition depends on the food intake. So, food is the most important single factor for health and fitness. Let us define and describe food, nutrition, health and fitness Food can be defined as anything solid or liquid which when swallowed, digested and assimilated in the body provides it with essential substances called nutrients and keeps it well. It is the basic necessity of life. Food supplies energy enables growth and repair of tissues and organs. It also protects the body from disease and regulates body functions. Nutrition is defined as the science of foods, nutrients and other substances they contain; and of their actions within the body including ingestion, digestion, absorption, metabolism and excretion. While this summarises the physiological dimensions, nutrition has social, psychological and economic dimensions too. Dietetics Dietetics is a field of science that determines how nutrition and good eating affect our overall health. While this field offers a strong focus on public health, its main purpose is to educate everyone on the importance of making proper and smart dietary choices. Dietary Requirements of Human Body Our diet contains many food items which are obtained from different sources. The food may be obtained from animal or vegetable sources. We already know that food comprises constituents like proteins, carbohydrates, fats and supplementary substances such as minerals, vitamins and water that are vital for life. These constituents are known as nutrients. For proper functioning of our body, we need to consume body building foods (e.g., milk, meat, poultry, fish, eggs, pulses, groundnuts); energy giving foods (e.g. cereals, sugar, roots, fats and oils); and protective foods (e.g. vegetables, fruits). Nutrients Nutrients are the compounds in food that provide us with energy that facilitates repair and growth and helps to carry out different life processes. Not all nutrients provide energy but are necessary for some form or the other. These nutrients are divided into two categories: Macronutrients, which are required by the body in large amounts. Micronutrients, which are required by the body in small amounts Above nutrients could be obtained from the environment. Macronutrients provide energy to a living being for the function of the metabolic system. They provide massive energy has it is converted used to obtain energy. Macronutrients include fats, proteins, and carbohydrates. Micronutrient provides essential components for metabolism to be carried out. They also build and repair damaged tissues in order to control the body process. Micronutrients include calcium, iron, vitamins, iron, minerals and vitamin C. The food we consume breaks down to simpler products before it is absorbed and utilised by the body. These simpler substances are called nutrients. Our body utilises nutrients for building and repairing, obtaining energy and for protection from diseases. What is nutrition? The term nutrition is related to our food intake and dietary patterns and utilisation of protein, carbohydrate, fat, vitamins and minerals to maintain our health. Most of the natural food items contain more than one nutrient. Let us understand various nutrients contained in different food items. Proteins Proteins are called building blocks of our body. About 20 per cent of our body weight comes from proteins. Proteins are essential for growth and repair of muscle and other body tissues. Proteins are made of amino acids that contain the elements carbon, hydrogen, oxygen and nitrogen. We obtain proteins from animal as well as vegetable sources. Proteins of animal origin are found in milk, eggs, cheese, fish and meat. Proteins from these sources contain all the essential amino acids (EAA) in adequate amounts. Vegetable proteins are found Carbohydrates Carbohydrates are the main source of energy for our body. There are three major categories of carbohydrates, viz. starch, sugar and cellulose. Our body breaks down sugar and starch into glucose to provide energy. Cellulose does not have any nutritive value per se, but is a major contributor of dietary fibres. Dietary fiber or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes Excess carbohydrates are converted into fat by the liver and stored in the adipose tissues in our body. Carbohydrates are of two types – simple and complex. Simple carbohydrates are quick energy foods, e.g., sugar. Sources of simple carbohydrates are natural fruits, milk and milk products, and vegetables including potatoes and carrots. Complex carbohydrates are better sources of energy than sugar since these are released slowly. Sources of complex carbohydrates are breads, cereals (rice, wheat, bajra, corn, barley, ragi, etc.). We should consume starch and natural sugar and eat whole grains, rice, bread, cereals and fruits to obtain adequate amount of carbohydrates. Fast food items such as pizza, pasta, noodles, etc. are rich in carbohydrates only and cannot replace a balanced meal. Fats Fats and oils are concentrated sources of energy. Fats are substances that our body stores for future use. These are classified as simple lipids (e.g., triglycerides), compound lipids (e.g., phospholipids), and derived lipids (e.g., cholesterol). Fats may be obtained from animal or vegetable sources. The major sources of animal fats are ghee, butter, milk, cheese, eggs, fish and meat. The sources of vegetable oils are groundnut, mustard, sesame, coconut, etc. Excess carbohydrates are converted into fats. Fast food items like pizza, samosas, burgers are rich sources of fat. Therefore, children who consume only fast-food items tend to become obese. Fats in the correct amounts are necessary for the proper functioning of our body. Many fat-soluble vitamins need to be associated with fats in order to be effectively absorbed by the body. They also provide insulation to the body. They are an efficient way to store energy for longer periods. Vitamins Vitamins are organic substances that we require in adequate quantities for good health. Our body, however, cannot synthesise them. Therefore, we need to consume their natural sources such as fruits and vegetables. Vitamins are divided into two groups–fat-soluble vitamins (Vitamins A, D, E, and K) and water-soluble vitamins (Vitamins of B group and Vitamin C). Each vitamin has a specific function and its deficiency, leads to a particular deficiency disease. The word vitamin is a combination of Latin words “vita” and “amine” which means life and nitrogen respectively. 1. Vitamin A- retinol- night blindness, and keratomalacia (Keratomalacia is an eye disorder that involves drying and clouding of the cornea ) 2. Vitamin D- calciferol – Rickets (Rickets is the softening and weakening of bones in children, usually because of an extreme and prolonged vitamin D deficiency) and Osteomalacia (bone softening) 3. Vitamin E- tocopherol - sterility 4. Vitamin K- phylloquinone – Haemorrhage (Haemorrhage is the medical term for bleeding) 5. Vit C- Ascorbic acid- scurvy- Minerals Minerals are the nutrients that are very essential for proper growth and functioning of our body and are required in small amounts. Calcium, Chlorine, Copper, Fluoride, Iodine, Iron, Magnesium, Manganese, Phosphorus, Potassium, Sodium and Zinc are essential mineral nutrients. Calcium- bone health Iodine- thyroid Magnesium- neurological Manganese= metabolism of carbohydrates Fluoride - tooth and bone weakness Potassium, Sodium - blood pressure Water- Vital nutrient that carries out all biochemical reactions Water is a nutrient and it makes up almost 70 per cent of our body weight. We need water to break down complex food molecules, and transport food, chemicals and gases throughout the body. It acts as the medium for biochemical reactions and is also required to eliminate the wastes as urine and sweat. We should take 8 – 10 glasses of potable water per day. Inadequate water intake leads to dehydration. Therefore, intake of water in proper proportion is important. We should never substitute water with coffee, tea or soft drinks Functions of Nutrients The important functions of nutrients include: a. They are the main source of energy for the body. b. They help in building and repairing body tissues. c. Increases the absorption of fat-soluble vitamins. d. Helps in the synthesis of collagen. e. Provides proper structure to the blood vessels, bones and ligaments. f. They also help in maintaining the homeostasis of the body. 2. The Importance of Good Nutrition Most people know good nutrition and physical activity can help maintain a healthy weight. But the benefits of good nutrition go beyond weight. Good nutrition can help: Reduce the risk of some diseases, including heart disease, diabetes, stroke, some cancers, and osteoporosis Reduce high blood pressure Lower high cholesterol Improve your well-being Improve your ability to fight off illness Improve your ability to recover from illness or injury Increase your energy level 3. Balanced Diet You have already learnt in earlier classes that a diet which contains all the essential nutrients like proteins, carbohydrates, fats, minerals and vitamins in the proportion required for the normal growth and development of the body, is called balanced diet. The quantity of nutrients in a balanced diet will always vary with age, sex and physical activities undertaken by an individual. 4. Assessing the BMI Body Mass Index (BMI) is an index of weight for height that is commonly used to classify adults as underweight, overweight and obese. It is obtained by dividing the weight in kilograms by the square of the height in metres (kg/m2). For example, an adult who weighs 70kg and whose height is 1.75m will have a BMI of 22.9. With the metric system, the formula for BMI is weight in kilograms divided by height in meters squared Recommended Dietary Allowances (RDAs) Recommended Dietary Allowances (RDAs) are the levels of intake of essential nutrients that, on the basis of scientific knowledge, are judged by the Food and Nutrition Board to be adequate to meet the known nutrient needs of practically all healthy persons. Recommended Dietary Allowances = Requirements + Margin of safety A balanced diet takes care of the following aspects. I. Includes a variety of food items II. Meets the RDA for all nutrients III. Includes nutrients in correct proportions IV. Provides a safety margin for nutrients V. Promotes and preserves good health VI. Maintains acceptable body weight for height 6. Types of Malnutrition The word " Malnutrition" comes from the prefix "mal-" which means "bad". Malnutrition refers to deficiencies or excesses in nutrient intake, imbalance of essential nutrients or impaired nutrient utilization. 1. Under-nutrition It does not occur in a single day’s food intake. Deficiency caused by undernutrition affects us after long term of negligence. An under-nourished child cannot grow fully, physically and mentally. In most of the developing countries, under-nutrition is a threat to public health as it leads to illness and even death. In addition to inadequate intake of nutrients, under-nutrition is also the result of mal absorption of food, addiction to drugs or loss of nutrients from body due to various medical reasons. Under-nutrition may lead to deficiency diseases, like protein deficiency diseases which include kwashiorkor, marasmus, mineral deficiency diseases like goitre, anaemia; and vitamin deficiency diseases like scurvy, beriberi - thiamine (also spelled thiamin), or vitamin B-1 and rickets. Ignorance, lack of education and poverty led by relatively high food prices, natural disasters causing insufficient agricultural productivity and unhealthy dietary practices are some important common causes of under-nutrition. Undernutrition continues to be a significant health problem for children and adults in India. The National under-nutrition is high among children. At present, 40 per cent children of less than five years of age in our country are underweight. For the management of under-nutrition, improvement in nutritional status is required. The Government of India provides mid-day meals to the students of up to elementary stage during school hours. Many myths and taboos about diet are also responsible for under-nutrition in our country. Due to ignorance and illiteracy, locally available nutritious food is not eaten. In case of new born babies, inadequate breastfeeding is a major cause of undernutrition. 2. Over-nutrition Over-nutrition is also a form of malnutrition that results from overeating and excessive intake of specific nutrients like carbohydrate and fat. Inadequate exercise and overeating are the major causes of overweight. Due to intake of excessive food, adipose tissue increases abnormally in the body that enlarges or the number of fat cells increase leading to obesity. We find obese persons bulky and overweight because of the accumulation of fat in the body. People who eat more need to burn more calories, otherwise surplus calories are stored as fat. In modern societies obesity has become an epidemic. It occurs in both developed and developing countries and affects children as well as adults. In addition to overeating and inactivity, the major reasons of overweight and obesity are sedentary life style, emotional problems and physiological disturbances including genetic factors. Metabolic and digestive disorders take place due to over-consumption of fats, fast foods, soft drinks and refined white flour carbohydrates, combined with low fibre intake. Overweight and obese children and adolescents frequently grow to become obese adults. Obesity tends to run in families, suggesting a genetic link too, as families share common dietary and physical activity patterns, attitude, lifestyle and habits which contribute to obesity. Planning for balanced diet and regular exercise is of utmost importance to prevent overweight and obesity. Eating disorders Eating disorders are severe disturbances in eating behaviour commonly seen among adolescents between ages 14 to 18 years. Disordered eating patterns are either characterised by refusal of food to maintain the body weight or recurring binge eating followed by vomiting. The former restrictive type disorder is known as Anorexia Nervosa and the later, Bulimia Nervosa. Most people do not seek help for eating disorders; some may not even be aware that they have a problem. Anorexia Nervosa (AN) (Refusal to eat food) Anorexia Nervosa is a psychological disorder caused by under-nutrition. People with such disorder become thin and lose a lot of weight. An obsessive fear of gaining weight occurs in such cases. Anorexia nervosa is an attempt to use food and weight to deal with emotional problems, physical changes, peer pressure and stress. It is a serious mental illness with a high incidence of morbidity and mortality. Extreme fasting, indulging in over exercise, dieting may result in anorexia nervosa. Teenage girls and young women are more likely to develop this disorder. However, this disorder can occur during adulthood too. Bulimia Nervosa (Recurrent binge eating) Bulimia Nervosa is an eating disorder characterised by recurrent binge eating, followed by compensatory behaviour. The most commonly observed behaviours include defensive vomiting, sometimes called purging, fasting, using laxatives and over- exercising. The onset of bulimia nervosa is generally observed during mid to late adolescence. It is 20 times more common in females. Bulimia nervosa is rarely seen in those under 14 years. It has also been observed that there is higher incidence of major depressive disorder in close relatives of patients with bulimia nervosa. The common causes of the disorder are family problems, inability to adjust in society, lack of self-identity, conflict, problem with body image, depression and other psychological problems. The person tries to express emotions that are otherwise difficult, becomes extremely engaged with emotions and is so tied up with a relationship with food and weight that it becomes difficult for him/her to deal with it. Health problems caused by both the above conditions include: a. Tooth decay, toothaches, swollen gums, gum disease (gingivitis), and erosion of tooth enamel, which are caused by acid in the mouth due to vomiting. b. Osteoporosis. c. Abnormal heart beat. d. Dehydration, which can lead to weakness, fainting. e. Fainting due to low blood pressure. f. Low body temperature. g. Suicide risks when a person feels discouraged due to presence of one of the conditions or has ongoing body image issues. Anorexia and bulimia can lead to delay in the onset of menstruation in girls. There is a need to focus on fitness rather than on weight reduction. Sitting in front of TV or computer for long hours, eating junk food, or having high calorie drinks add to obesity. It is seen not only in the affluent section but also in urban poor. Since obesity is more a lifestyle disease, it needs intervention at the level of the person himself/herself and at the level of the entire family, school and the community. Proper eating habits, diet and exercise are the essential requirements for physical fitness and management of weight.