Unit 1 Concept of Food and Nutrition PDF

Unit1 Concept of Food and Nutrition a) Definition of Food, Nutrients, Nutrition, Health, balanced Diet (b) Types of Nutrition- Optimum Nutrition, under Nutrition, Over Nutrition (c) Meal planning- Concept and factors affecting Meal...

Unit1 Concept of Food and Nutrition a) Definition of Food, Nutrients, Nutrition, Health, balanced Diet (b) Types of Nutrition- Optimum Nutrition, under Nutrition, Over Nutrition (c) Meal planning- Concept and factors affecting Meal Planning (d) Food groups and functions of food Food is a substance that supplies energy for nutritional purposes. The survival of people, animals, and plants all depend on this vital source of energy. Animals and people eat food, while plants absorb a food source. Without food sources, animals, people, and plants will die, so food is needed to support life. It is consisting essentially of protein, carbohydrate, fat, and other nutrients (vitamins and minerals) used in the body of an organism to sustain growth and vital processes and to furnish energy. The food that people eat comes in many types with different tastes, textures, and nutritional content. One food may be high in fat and calories, while another food maybe healthier, but lacks a delicious taste. Plants, unlike humans and animals, must get energy from photosynthesis. In the food chain, plants use photosynthesis, which allows plants to be a food source for animals and humans. Without plants using photosynthesis, there would be no food for other lifeforms. Food and our diet A healthy diet should contain mostly fruits and vegetables because these foods provide fibre and many nutrients. The types of food ingested will have an impact on the health of a being. Examples of fruits and vegetables are apples, carrots, cucumbers, oranges, and grapefruits. Grains consist of rice, bread, and oatmeal. Whole grains are a healthier choice of grains. Whole grain bread is better than regular white bread. Protein foods include meats like beef, poultry, lamb, and pork. Nuts and beans are another great source of protein which the body needs to survive. There are also soy-based alternatives, which are protein sources. The soy-based meat replacements come in a variety of forms like paddies, links, nuggets, and even ground versions. Dairy products are a great source of calcium, which is needed for bone health. Examples of dairy sources include milk, cheese, yogurt, and cottage cheese. Soy and nut-based milk products are popular dairy replacements for people with lactose problems. The five major food groups-  (a) Vegetables, (b) Fruits, grains, (c) Protein foods, and (d) Dairy ✓ A healthy diet should contain mostly fruits and vegetables because these foods provide fibre and many nutrients. ✓ The body uses proteins for building materials for organ walls, skin, hair, muscle, and other uses. ✓ Protein foods include meats like beef, poultry, lamb, and pork. ✓ Nuts and beans are another great source of protein which the body needs to survive. ✓ There are also soy-based alternatives, which are protein sources. ✓ The soy-based meat replacements come in a variety of forms like paddies, links, nuggets, and even ground versions. ✓ Dairy products are a great source of calcium, which is needed for bone health. Examples of dairy sources include milk, cheese, yogurt, and cottage cheese. ✓ Soy and nut-based milk products are popular dairy replacements for people with lactose problems. ✓ Milk, meat, eggs and fish are good sources of animal proteins while legumes and nuts are good sources of plant protein. ✓ Animal protein sources are considered to be of high quality compared to plant sources, apart from soybeans. ✓ Consumption of a variety food that can potentially supply all the body nutritional requirements on a daily basis Classification of foods according to their functions Foods may be classified according to their functions in the body: a) Energy-giving foods (“GO” foods) ✓ Foods rich in carbohydrates and fats are called energy-giving foods or “GO” foods. ✓ They provide energy to the body and are essential for physical activity and basic functioning of the body. ✓ Foods like cereals, roots, tubers, starchy fruits and vegetables oils, milk, butter and ghee are good sources of energy.  b) Body-building foods (“GROW” foods) ✓ Foods rich in protein are called body-building foods or “GROW” foods. ✓ These foods help to maintain life and promote growth, repair worn out and damaged body tissues. ✓ “GROW” foods come from animal and plant sources. ✓ GROW” foods come from animal and plant sources. Milk, meat, eggs and fish are good sources of animal proteins while legumes and nuts are good sources of plant protein. ✓ Animal protein sources are considered to be of high quality compared to plant sources, apart from soybeans. c) Protective (“GLOW” foods) ✓ Foods rich in minerals and vitamins are known as protective or “GLOW” foods. ✓ They are essential for promoting body immunity and regulatory functions. ✓ Fruits and vegetables are the main sources of “GLOW” foods. Fortified foods, including iodized salt, are also good sources of “GLOW” foods  Nutrients Nutrients are chemical compounds in food that are used by the body to function properly and maintain health. Examples include proteins, fats, carbohydrates, vitamins, and minerals. ✓ The food we consume breaks down to simpler products before it is absorbed and utilized by the body. These simpler substances are called nutrients. There are two types of nutrients: ✓ Macronutrients are required by the body in large amounts include carbohydrates, proteins and fat and most energy used by human and animal bodies. ✓ Micronutrients are required by the body in small amounts and include vitamins and minerals Nutrients in food are divided into three major categories: macronutrients, micronutrients and water. 1) Macronutrients These are required in large amounts: Carbohydrates Proteins Fats/oils Nutrition Nutrition is the process of providing or obtaining the food necessary for health and growth. It broadly encompasses all actions necessary for obtaining, handling, preparing, serving, eating and utilization of food by the body. Nutrition is about eating a healthy and balanced diet. Food and drink provide the energy and nutrients you need to be healthy. Many factors play a part in a person's body staying healthy and fit, and one of the most significant contributors is the food that they eat. While nutrition is easy to lose sight of in the fast-paced days of busy lives, it is critical to sustaining life-long health. Nutrition science also includes behaviours and social factors related to food choices. The foods we eat provide energy (calories) and nutrients such as protein, fat, carbohydrate, vitamins, minerals, and water. Eating healthy foods in the right amounts gives your body energy to perform daily activities, helps you to maintain a healthy body weight, and can lower your risk for certain diseases such as diabetes and heart disease. There is no question that sugary drinks and snacks provide few nutrients that affect energy, growth, and immune system support. In contrast, many nutrient-dense foods such as vegetables, fruits, whole grains, and healthy proteins contribute to the body's ability, wellness, energy, and growth. Studies demonstrate that children and adults who are provided a nutrient-dense diet have stronger health and immune systems, a lower risk of diabetes and cardiovascular disease, and live longer lives. In addition, children and adults with proper nutrition are able to focus better, learn more easily, and be more productive. Nutritionists work with individuals and populations to determine what foods fuel bodies with the appropriate vitamins, minerals, and nutrients in order to maintain health or, in some cases, improve health. There is a multitude of options to work in a field related to nutrition, including government agencies, schools, clinics, and research facilities. Plus, while the basics of nutrition might be similar, individual needs can vary based on environment and genetics. Hence, nutrition is a highly varied field. Optimum nutrition ✓ When a person receives and utilizes essential nutrients in proper proportions according to the requirements of the body it is called optimum nutrition.  ✓ It is the state of a well-balanced diet in which all the essential nutrients is supplied to meet the body's requirements. Nutritional status ✓ It is the condition of the body which relates to consumption and utilization of food. The nutritional status of a person may be either good or bad adjudged by the adequacy or excessiveness of nutrient intake and their utilizations. Good nutritional status ✓ It is the state of a well-balanced diet in which all the essential nutrients is supplied to meet the body's requirements. Such a person is characterized with optimum nutrition. Poor nutritional status A poor nutritional status refers to the state of inadequate or excessive intake or improper utilization of the nutrients to meet the body's requirements, Thus, overeating is also considered as poor nutritional status and this may result into overweight person. Under-nutrition It refers to the state of low food intake in human body. It does not occur in a single day’s food intake. Deficiency caused by under-nutrition 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. According to the 2022 Global Hunger Index, India ranks 107th out of 121 countries, with a moderate hunger score of 28.2. This means that around 224.3 million people in India are undernourished. India ranks 131 out 189 countries on HDI as per the 2020 Global Human Development Report published by the United Development Program (UNDP) According to Ministry of Women and Child Development (2006), "Nutrition is the science of food and its relationship to health. Good Nutrition is a fundamental requirement for positive health, functional efficiency and productivity.  Nutritional status is internationally recognized as an indicator of national development. Nutrition is both an input into and an output of the development process. A well-nourished healthy workforce is a pre-condition for successful economic and social development, and as such food security, nutrition, health and sanitation are the responsibility of all development sectors and indeed of all citizens. In many developing countries including India, economic productivity has increased and impressive efforts have been made in nutrition interventions, but significant improvement in nutritional status has not accompanied these advances. Investing in nutrition has both economic and social benefits. Improved nutritional status has an enhancing effect on investments in other sectors such as health, education and agriculture. Moreover, the enormous social and financial costs of malnutrition are averted when nutritional status is improved.” 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 overconsumption of fats, fast foods, soft drinks and refined white flour carbohydrates, combined with low fiber intake. ✓ Obesity ✓ Overweight and obesity are not the same. Obesity is a health condition in which excess body fat accumulates to the extent that it may have an adverse effect on health and  reduce life expectancy. When body fat content exceeds 25 per cent for men or 30 per cent for women of the total body weight, a person is called obese. ✓ 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 meters (kg/m2). For example, an adult who weighs 70kg and whose height is 1.75m will have a BMI of 22.9. BMI Category 25 Kg/m2 Obese National Programme for Prevention and Control of Cancer, Diabetes, Cardiovascular Diseases and Stroke: A Guide for Health Worker. Directorate General of Health Services, MoHFW; GOI, 2011 Balanced diet ✓ 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. ✓ The safety margin takes care of the days we fast, or the short-term deficiency of certain nutrients in the daily diet. If the balanced diet meets the Recommended Dietary Allowances (RDAs) for an individual, then the safety margin is already included since RDAs are formulated keeping extra allowances in mind. Recommended Dietary Allowances = Requirements + Margin of safety A balanced diet takes care of the following aspects.  1. Includes a variety of food items 2. 2. Meets the RDA for all nutrients 3. Includes nutrients in correct proportions 4. Provides a safety margin for nutrients 5. Promotes and preserves good health 6. Maintains acceptable body weight for height Health and Fitness According to World Health Organization (WHO) ‘‘Health is the state of complete physical, emotional, and social well-being, not merely the absence of diseases or infirmity.’’ This definition has remained unchanged since 1948. All of us want to maintain positive health, i.e., a perfect blend of physical, social and mental. Taking adequate amounts of essential nutrients in our diet is necessary to maintain positive health. Physical health is probably the most easily understood aspect. Mental health can be defined as “A state of emotional and psychological well-being in which an individual is able to use her or his cognitive and emotional capabilities, function in society, and meet the ordinary demands of everyday life.” ✓ The absence of a recognized mental disorder is not necessarily an indicator of mental health. ✓ One way to assess mental health is to see how effectively and successfully a person functions ✓ Feeling capable and competent, being able to handle normal levels of stress, maintaining satisfying relationships, and leading an independent life; and being able to ‘bounce back’ or recover from difficult situations are all signs of good mental health. Physical fitness is good bodily health; it is the result of regular exercise, proper diet and nutrition, and proper rest for physical recovery. The term physical fitness is used in two ways: general fitness (a state of health and well-being) and specific fitness (a task-oriented definition based on the ability to perform specific aspects of sports or occupations). Physical fitness is the capacity of the heart, blood vessels, lungs, and muscles to function at optimal efficiency. Earlier, fitness was defined as the capacity to carry out the day’s activities without undue fatigue. Physical fitness is now defined as the body’s ability to function efficiently and effectively in work and leisure activities, to be healthy, to resist diseases and to meet emergency situations. However, Fitness can also be divided into five categories: aerobic fitness, muscular strength, muscular endurance, flexibility, and body composition. Being fit prepares one to meet mental and emotional challenges. One feels strong and energetic if one is fit. If one is fit then he feels strong and energetic. Fitness provides one with the ability to meet routine physical demands with enough reserve energy to rise to a sudden challenge, such as running to catch a bus. Therefore, a well-nourished and fit person is better able to learn and has more energy, stamina, and self-esteem. A healthy eating pattern along with regular exercise will certainly help to remain fit. Teenagers between the ages of 12 and 18 who have unhealthy eating behaviours and are undernourished develop eating disorders. Meal Planning One of the simplest ways to plan a balanced diet is to divide foods into groups and then make sure that each group is included in the meals. A food group consists of different foods which have common characteristics. These common features may be the source of food, the physiological function performed, or the nutrients present. Foods can be grouped on the basis of the nutrients present in it. This classification varies from one country to another depending on many factors. The five-food group classification is used in India as a guide to meal planning. Many factors have been considered while compiling these groups such as availability of food, cost, meal pattern, and deficiency diseases prevalent. Not all foods in each group are equal in their nutrient content. That is why a variety of foods from each group should be included in the diet. There are five basic food groups suggested by the Indian Council of Medical Research (ICMR). These include: Cereals, grains and products Pulses and legumes Milk and meat products Fruits and vegetables Fats and sugars Food groups Main Nutrients supplied I-Cereals grains and products: Rice Wheat, Energy, Protein, Invisible fat, Vitamin-B1, Ragi, Bajra Maiz, Jowar, Rice Flakes, Wheat Vitamin-B2, Folic Acid, Iron Fibre. Flour II Pulses and legumes: Bengal Gram, Black Energy, Proteins, Invisible Fat, Vitamin-B1, Gram, Green Gram, Red Gram, Lentil (Whole Vitamin-B2, Folic Acid, Calcium, Iron, Fibre. as well as Dals), Cowpea, Peas, Rajmah, Soyabeans, Beans. III Milk, Meat and Products: Milk Milk, Protein, Fat, Vitamin – B12, Calcium. Curd, Skimmed milk, Cheese Protein, Fat, Meat Chicken, Liver, Vitamin – B2 Fish, Egg, Meat. IV. Fruits and Vegetables Fruits Mango, Guava, Tomato Ripe, Papaya, Carotenoids, Vitamin – C, Fibre. Orange. Sweet Lime, Watermelon Invisible Fats, Carotenoids, Vitamin – B2. Vegetables (Green Leafy) Folic Acid, Calcium, Iron, Fibre. Amaranth, Spinach, Drumstick leaves, Coriander leaves, Mustard leaves, Fenugreek leaves. Carotenoids, Folic Acid, Calcium, Fibre Other Vegetables Carrots, Brinjal, Ladies finger, Capsicum, Beans, Onion, Drumstick, Cauliflower. V. Fats and Sugars Fats Butter, Ghee, Hydrogenated oils, cooking oils Energy, Fat, Essential like Groundnut, Mustard, Coconut. Fatty Acids Sugars Sugar, Jaggery Energy Nutritive value of Indian foods. Hyderabad. National Institute of Nutrition, ICMR One gram of carbohydrate releases 4 Kcal. of energy protein releases 4 Kcal. of energy fat releases 9 Kcal. of energy Guidelines for using the basic food groups The five-food group system can be used both for planning and assessing balanced diets. It is a simple daily food guide which can be used for nutrition education as well. Guidelines could be adopted depending on the food groups. Include at least one or a minimum number of servings from each food group in each meal. Make choices within each group as foods within each group are similar but not identical in nutritive value. If the meal is vegetarian, use suitable combinations to improve the overall protein quality of the diet. For example, serving cereal-pulse combinations or including small quantities of milk or curds in the meal. Include uncooked vegetables and fruits in the meals. Include at least one serving of milk to ensure a supply of calcium and other nutrients as milk contains all nutrients except iron, vitamin C, and fibre. Cereals should not supply more than 75 per cent of total Kcal/ Calories. Note: In planning balanced diets, food should be chosen from each group in sufficient quantity. Cereals and pulses should be taken adequately, fruits and vegetables liberally, animal foods moderately and oils and sugars sparingly. The food guide pyramid is a graphic depiction of the daily food guide. The size of each section represents the number of daily servings recommended. The broad base at the bottom conveys the message that grains should be abundant and form the foundation of a healthy diet. Fruits and vegetables appear at the next level, showing that they have a less prominent, but still important place in the diet. Meats and milks appear in a smaller band near the top. A few servings of each can contribute valuable nutrients such as proteins, vitamins and minerals, without too much fat and cholesterol. Fats, oils and sweets occupy the tiny apex, indicating that they should be used sparingly. Vegetarian Food Guide Vegetarian diets rely mainly on plant foods: grain, vegetables, legumes, fruits, seeds, and nuts. Some vegetarian diets include eggs, milk products, or both. People who do not eat meats or milk products can still use the daily food guide to create an adequate diet. The food groups are similar and the number of servings remains the same. Vegetarians can select alternatives to meat such as legumes, seeds, nuts, tofu and for those who eat them, eggs. Legumes, and at least one cup of dark leafy greens, help to supply the iron that meats usually provide. Vegetarians who do not drink cow’s milk can use soy ‘milk’- a product made from soyabeans that provides similar nutrients if it has been fortified with calcium, vitamin D, and Vitamin B12 (i.e., these nutrients are added). The food guide pyramid emphasises foods from the five food groups shown in the three lower sections of the pyramid. Each of these food groups provides some, but not all of the nutrients you need. Foods in one group cannot replace those in another. No one food group is more important than another- for good health you need all of them. Dietary Patterns in Adolescence Healthy eating is vital for the teenager’s health and well-being. The nutritional needs of adolescents vary tremendously, but generally increase due to rapid growth and changes in body composition that occur during puberty. Good eating habits help prevent chronic illness in the future, including obesity, heart disease, cancer and diabetes. Studies of nutrient intakes have shown that adolescents are likely to obtain less vitamin A, thiamine, iron, and calcium than recommended. They also ingest (consume) more fats, sugar, protein, and sodium than is currently thought to be optimal. What are the commonly adopted eating habits of adolescents and why are they important to recognise? Understanding diet patterns will help us to be better prepared to evaluate the nutritional adequacy of diets and ensure that they are meeting the minimum requirements to maintain health and well-being. Among the more common eating idiosyncrasies include skipping meals, consuming fast foods in a routine way, avoiding fruits and vegetables, snacking frequently and dieting. By addressing each of these issues individually you can ensure that you are meeting the minimum nutritional requirements. Irregular meals and skipping meals: The numbers of meals teenagers miss and eat away from home increases from early adolescence to late adolescence, reflecting the growing need for independence and time away from home. The evening meal appears to be the most regularly eaten meal of the day. Girls are found to skip the evening meal, as well as breakfast and lunch, more often than boys. In some homes with limited resources, the adolescents may not even receive adequate number of meals or amounts, leading to nutrient deficiency. Breakfast is frequently neglected and is omitted more often by teenagers and young adults under 25 years of age than by any other age groups in the population. A likely explanation as to why girls are more apt to miss breakfast than are boys is the pursuit of thinness and frequent attempts at dieting. Many teenage girls believe that they can control their weight by omitting breakfast or lunch. In fact, this approach is likely to accomplish just the opposite. By mid-morning or lunchtime, they may be so hungry that they overcompensate for the “saved kilocalories.” As a matter of fact, skipping breakfast can slow your metabolism contributing to weight gain and poor performance. Snacking: Snacking is probably a survival technique for teens. Snacking does not have to be a bad habit. It can help maintain energy levels, particularly in active and growing adolescents. Many adolescents fail to eat three regular meals per day because of the ‘skipping meal’ factor. Thus, snacking can actually be beneficial to ensure adequate intake of essential nutrients. However, surviving only on snacks is harmful to health. Fast foods: Adolescents, particularly in urban areas, are more apt to eat fast food because it is convenient and typically a social affair, and they may believe it is the fashion of the day. Fast food is often packed with fat and “empty calories”. We should make smart food choices even when visiting fast food restaurants. Table 2 provides important information about fast foods. Dieting: Obesity is becoming a crucial problem among adolescents. Intervention is needed to maintain ideal body weight among the entire population. If this is not maintained, 80 per cent of them will stay overweight as adults. This can put them at risk for many medical problems, including diabetes, high blood pressure, high cholesterol and sleep apnoea (a sleep disorder). Unhealthy Dieting: Dieting unsupervised by experts can lead to dangerous outcomes including eating disorders in teens. Some symptoms of dieting include: skipping meals, ‘binge’ eating, fasting or use of laxatives or diet pills. Consequences of such dieting include its possible association with cycles of weight loss and regain that increase the likelihood of developing eating disorders and obesity, lowered self-esteem and other psychological problems. This can lead to increased cardiovascular risk (heart problems) and possible mortality. Conclusion: One approach to overcome the problems related to dieting is to attempt to eliminate the term ‘diet’ and replace it with ‘healthy eating’. If you regularly incorporate healthy lifestyle and dietary practices into your life, you are less likely to diet on a consistent basis. Recognising good eating habits is the first step towards encouraging healthy diets. It is best to adopt a healthy lifestyle that incorporates sound eating habits and regular exercise. Eating disorders at adolescence Adolescence is associated with rapid physical growth and body-image development eating disorders are of special concern at this time. These changes intensify associated self-esteem problems. Anorexia nervosa, for example, is a disorder so tied to body image distortion that it is most commonly seen in adolescence, the period when a person is struggling with self-identity and most vulnerable to body image problems. Progress in adopting a normal adult body image will be interrupted for the teenager with an eating disorder. Bulimia It is another type of eating disorder. Bulimia often begins in late adolescence or early adulthood after a series of various unsuccessful weight reduction diets. Those with bulimia indulge in bingeing (overeating) and inducing purging by vomiting or using laxatives. Although more common in females, about five to ten per cent of all eating disorders occur in males too. Note: Anorexia and bulimia can have serious consequences such as convulsions, renal failure, irregular heartbeats and dental erosion. In adolescent girls, anorexia can delay the onset of menstruation, permanently minimise stature and result in osteoporosis (weakening of bones).