Food is a necessity of life and its use is a skill and science
Since the dawn of civilization, man has harnessed natural resources for survival. Over the centuries, man evolved from being a hunter-gatherer to a cultivator of several food crops and domesticated animals to ensure food supply. With progress of time, industrial development and mechanization has changed the scenario of food production. Further, scientific advances in molecular biology, genetics, plant breeding, nutrition science and biotechnology, have brought sea changes in accessibility to food and health services. From the “green revolution” in the 1960's, the world is now sailing rapidly towards “gene revolution”. In India, the green revolution made remarkable contributions towards meeting the growing demands of the continually increasing population. After decades of research, there has been a paradigm shift from a focus largely on food security to now encompass nutrition and health security. Many technologies like food irradiation, biofortification, food fortification and approaches such as dietary diversification have not only helped to achieve adequate food supplies but supported efforts for ensuring good nutrition and health of the population.
Despite this tremendous improvement in food production, accessibility to nutritional and health services seemingly lag behind. The report of the Food and Agriculture Organization (FAO, 2009) indicated that in the world, 2 billion people sleep hungry, with more than 60% being from South Asian countries including India. In spite of the economic progress in our country, a substantial proportion of the population suffers from one or more nutritional problem and malnutrition looms large on India's horizon.
Maternal nutrition plays a critical role in the unresolved problem of malnutrition. Low birth weight babies are born of undernourished, underweight and anemic mothers. Such infants are at high risk of morbidity and mortality. Mortality among infants and children under 5 years of age is primarily because of the deficiency of energy, protein and other important nutrients.
Survival, however, does not guarantee good health and productivity. Undernourished children continue to have impaired growth, maturation and poor adjustments with self and the environment. In adulthood, they may tend to become victims of non-communicable diseases. Genes for these metabolic conditions may be programmed during intrauterine life and further unhealthy lifestyle, poor dietary habits and vocational demands set the stage for chronic poor health conditions.
Where is the real crisis? Health indicators for India including hunger index, malnutrition, poverty, morbidity and mortality indicate that there is need for serious concern. Innumerable studies and surveys at various levels reveal that one important factor is the poor availability of food to people from low socioeconomic background as well as distribution within the family. Sociocultural biases play a strong role in dietary patterns. Inadequate knowledge with regard to nutrition and health among both educated and uneducated people is another contributory factor.
At the turn of this century, increasing globalization, improvements in transportation and technological development have changed dietary practices and lifestyles especially in cities. A wide variety of foods, such as bread/chapatti/rice, milk, fruits, vegetables are commonly consumed. Besides this, pulses and legumes/beans, nuts or egg/meat/fish, etc. are also part of the daily meals. However, many foods are manufactured or modified in the food industry, such as soy nuggets, non-dairy cream, instant noodles, beverages, ready to eat snacks, breakfast cereals, etc. A wide array of processed foods is available, some of which are good for health but some may have unfavorable effects. Interestingly, many unhealthy foods are more attractive, palatable and irresistible. Many of them are produced by street vendors and help in satisfying appetite. Frequent indulgence in such foods, due to ignorance about their health consequences, may have adverse effects on health and nutritional status. Globalization and industrialization have further amplified prevalence of degenerative diseases like obesity, diabetes, hypertension, heart disease and cancer.
Since the early 1900's the arena of nutrition knowledge has widened through exhaustive research in nutrition science and it is recognized that nutrition is one of the core contributing factors to health and wellbeing. Scientific investigations on the sociocultural effects on diet and lifestyle have further changed the face of nutrition science. Renaissance of health systems has highlighted the tremendous potential of hidden valuable components in food, which are beneficial in health and healing. These components are functional foods, phytochemicals, nutraceuticals and dietary supplements. Many health conscious people are looking forward to naturally occurring food components in food products, to protect them from harmful effects of processing, use of chemical fertilizers and pesticides, occupational challenges, environmental fluctuations and thereby improve health status.
Food is one of the basic needs to sustain life. It is a reservoir of nutrients and other beneficial compounds. The health of a person is interlinked with the quantity as well as the quality of food eaten. Every person, irrespective of age, race, religion and culture eats food. There is uncountable number of cuisines and dishes in every region, community and religion to satisfy biological and sensory requirements. A considerable proportion of every person's life revolves around food; from thinking about it, procuring it, preparing and serving it to family/friends and for special occasions. Many people have to work hard to earn their daily ‘bread’ whereas for others, it is a matter of pleasure and enjoyment. Food is also a topic for discourse, discussion, research and development. Most industries are connected directly or indirectly with food. It is an integral part of our value systems, is associated with power and status, and is used as a symbol of hospitality and for pursuit of pleasure and happiness. Some parents may use food as a reward or punishment.
WHAT IS FOOD?
Food is an edible substance obtained from plant or animal sources. It nourishes the body and sustains life. Food must satisfy hunger and fulfills physiological, psychological, social and sensory needs. It also protects the body from diseases. Food contains the substances called nutrients that are necessary for growth, survival and different processes of the body.
Nutritious food is that which can fulfill the primary functions of the food. It provides sufficient energy and essential nutrients, helps in maintaining all biological processes of the body, maintains body weight and protects us from invasion of any harmful microorganisms and onset of any disease.
FUNCTIONS OF FOOD
Food is a consumable commodity and its functions vary widely. From the nutritional point of view, food must provide nourishment for:
- Maintenance of life
- Growth and development
- Functioning of vital organs
- Production of energy
- Protection of body
Food also fulfills psychological and social functions that are listed in Figure 1.1.
WHAT IS NUTRITION?
Nutrition is the science of food and its components, their actions, interactions and balance within the body. It includes the study of processing of food within the body (digestion, absorption, transport, function and disposal of end products) for its utilization for (i) provision of energy, (ii) building of body tissues and their repair (iii) protection from microorganisms, heat and other stressors.
“Human nutrition describes the processes whereby cellular organelles, cells, tissues, organs, systems and the body as a whole obtain and use necessary substances obtained from food (nutrients) to maintain structural and functional integrity” (Vorster and Haustvast, 2002). It also includes the influence of social, cultural, environmental, political and economic on food intake and thereby on nutrition and health.
Nutrition is a multidisciplinary science that includes combined knowledge of the physical (physics, chemistry) and biological sciences (physiology, molecular biology, biochemistry, genetics, microbiology, food science, pathology, and immunology) and social sciences (psychology, sociology, anthropology, economics, communication and marketing). Physical, social, psychological and economic factors greatly influence the nutritional and health status of the individual, society as well as the nation. Therefore, a nutritionist is required to integrate the relevant concepts from the varied disciplines.
The study of nutrition helps to make healthy food choices by understanding the following:
- The role of different nutrients in our body
- The nutritive value of foods
- Which foods are nutritious and healthy
- The Recommended Dietary Allowances (RDA) for different life stages
- What can happen if the right kind and right amount of food is not eaten
- How to design nutritious recipes
- How different processing methods can alter the nutritional quality of food
- Role of food and nutrition in health and disease.
WHAT ARE NUTRIENTS?
A nutrient is a chemical substance inherently present in numerous food sources that the body uses to obtain energy, build tissues and regulate biological functions. Nutrients play a critical role in health, nutrition and disease. The presence of nutrients in the diet is essential because their deficiencies can have adverse effects on health. The deficiency disorder can be reversed by putting the specific nutrient back into the diet. Thus, the significance of nutrients lies not only in promoting health but also in maintaining and bringing back the body into optimal health, e.g. severe deficiency of vitamin A can cause blindness, and excess intake causes hypervitaminosis.
Functions of Nutrients—Nutrients are required for:
- Regulation of body processes like temperature control, blood pressure, metabolism and waste disposal
- Structural integrity of bones, muscles and other tissues and cell membranes
- Energy production for physical activity, muscle contraction and other cellular functions
- Growth, development and repair
- Resistance to infection and protection from disease.
CLASSIFICATION OF NUTRIENTS
There are six classes of nutrients, namely carbohydrates, proteins, lipids, vitamins, minerals and water (Figure 1.2). In each class, there are a number of nutrients. More than 40 nutrients are involved in performing specific functions in relation to growth, development and maintenance of the human body. Nutrients have largely been divided into two categories based on the amount required by the body:
Macronutrients are organic nutrients needed in large quantity, generally in grams. They are indispensable sources of energy that humans and other living organisms require to perform all physical, physiological and metabolic activities. Their structures range from simple small molecules to large complex ones. Each of the large complex compounds consists of smaller building blocks that are eventually broken down in the body to perform metabolic functions. One of the common building blocks of carbohydrates is glucose. Proteins are made up of amino acids and fat is made from fatty acids.
Carbohydrates literally mean, “hydrates of carbon” and are composed of carbon, hydrogen and oxygen. Dietary carbohydrates are broken down into smaller units, generally ‘glucose’ in the alimentary canal. Glucose circulates through blood and reaches cells and tissues to release energy that is used for physical and metabolic activities. Carbohydrates occur in abundance in nature, particularly in plant foods. Cereals, pulses, sugar, milk and fruits are rich sources of carbohydrates whereas animal tissues contain very small amounts or are devoid of carbohydrates. Carbohydrates are a major source of energy (4 kcal/g).
Proteins are made up of small molecules called amino acids. They contain nitrogen in addition to carbon, hydrogen and oxygen. The human body requires approximately 20 amino acids.
Amino acids are obtained after protein is digested by the gastrointestinal tract. Protein and amino acids are required to form new molecules like proteins, hormones, enzymes, cells, tissues, organs. A wide variety of protein molecules is used to build and maintain the body structure and to regulate body processes. Dietary protein also provides energy (4 kcal/g). Meat, fish, poultry, egg, milk and milk products, pulses/legumes and nuts as well as cereals are sources of protein. Vegetables and fruits are, in general, poor sources of protein.
Lipids are substances present in the body such as triglycerides, cholesterol, phospholipids and fatty acids. The term lipids and fats are often synonymously used in nutrition science. Lipid/fat is obtained from dietary fats and oils like butter, ghee, groundnut/sunflower/safflower oil, etc. Lipids and dietary fats are made up of various fatty acids. They supply 9 kcal/g, i.e. two and a half times more energy than carbohydrates or protein. Besides supplying energy, lipids are carriers of fat-soluble vitamins; are precursors for synthesis of hormones and structural material for cell membranes. The amount of fat intake and the fatty acid composition influence the risk of developing non-communicable, chronic diseases.
These are required in small amounts, generally in milligram or microgram quantities. Micronutrients comprise vitamins and minerals. Vitamins have elaborate chemical structures and are organic in nature. They participate in biochemical reactions as coenzymes. They do not provide energy but some of them help in regulation of energy production and other functions. Minerals are inorganic, generally found in the earth's crust and water.
Vitamins are comprised of a large group of organic compounds, some of which are soluble in fats and oils, and others in water. The fat-soluble vitamins are Vitamins A, D, E and K. Water-soluble vitamins include thiamin, folic acid and vitamin C among many others. Vitamins play a vital role in energy release from carbohydrates, lipids and proteins; blood clotting and numerous metabolic processes.
Minerals are simple, singular inorganic elements and perform diverse functions in the body. Some of them are needed in relatively more quantity particularly when they are structural components of the body, such as calcium, phosphorus and magnesium. Some electrolytes like sodium and potassium also belong to this category. Some minerals are required in very minute amounts (µg) and hence are known as trace elements, e.g. selenium, manganese, chromium. Many minerals are cofactors for enzymes. They have specific functions and their deficiencies can cause havoc in the body.
This is one of the most important nutrients for survival. The human body contains more than 60% water; however, its proportion is even higher in infancy and childhood. Water is present outside as well as inside cells and helps in transporting the nutrients and metabolic products in and out of the cell. Acid-base balance, temperature regulation and lubrication of joints are other major functions of water. Body must maintain water balance.
Besides nutrients, there are other chemical substances that are important for health but may not be classified as nutrients. Plants synthesize two types of metabolites—primary and secondary. Primary metabolites include carbohydrates, proteins, lipids, vitamins, minerals that are basically used as nutrients. Secondary metabolites are enzymes, essential oils and phytochemicals. These phytochemicals are also important for life. Primary nutrients provide energy or perform other important functions in the body. Secondary metabolites promote and protect the human body from unwanted microorganisms and diseases. Phytochemicals include a wide range of compounds that exhibit health benefits.
Phyto is a Greek word meaning ‘plant’. Phytochemicals are non-nutrient, bioactive, chemical compounds found in different parts of plants. They have potential health benefits, help in promotion of health and provide protection against many infectious and non-communicable, chronic diseases. Though the mechanism of action of different phytochemicals is not fully clear, research data indicates that they confer beneficial effects on health, through their influence on hormonal, enzymatic and other regulatory processes occurring in the body.
Phytochemicals act as antioxidants and behave like anti-inflammatory, antiviral and antibacterial agents. They help in boosting immunity and some delay the aging process. They also help in detoxification of environmental pollutants and toxins. Richly colored foods like vegetables, fruits, tea, chocolate, nuts, flax seeds and legumes are rich in phytochemicals. Regular consumption, particularly of fruits and vegetables can work wonders. However, plants may also contain compounds like toxic substances or anti-nutrients that can have harmful effects and hence should be consumed with caution, care and guidance. Some commonly known phytochemicals include polyphenols, carotenoids, flavonoids, isothiocyanates, terpenes, etc. Food exhibiting health benefits due to the presence of these phytochemicals are called functional foods. These ingredients have also been incorporated in many health foods that are similar in appearance of popular food like biscuits, energy bars, nutribars, chywanprash, etc. Nutraceuticals and dietary supplements are also sources of ingestible bioactive compounds in the form of powders, capsules, gels. Bioactive compounds are also obtained from marine and other animal sources.
Nature has presented man with innumerable food sources. Thus, man has access to a very wide range of foods. Yet human beings do not always choose foods from the health point of view. Invariably, people choose food for many other reasons.
Food choices begin early in life and develop under the influence of environmental exposures and experiences. Initially, it is often guided by parents and people surrounding the child. Thus, the child develops certain food choices/food preferences by imitating them. From the beginning, taste, texture and gestures of people in relation to food, contribute the most in shaping food choices. Food habits formed during childhood are difficult to change later in life, especially in adulthood and old age. Individuals might adapt to new foods in different situations, but still relish most of the foods they liked and ate in their childhood.
Food choice is a process of decision making and sets a pattern of selection of food items for consumption. A wide range of determinants strongly influences food choices. These include age, gender, marital status, family composition, vocational demands, socioeconomic status, culture beliefs, climate, personality traits, and attitudes toward food.
Over a period of time, remarkable changes have occurred in food choices. Traditionally, people used to choose food on the basis of social and cultural beliefs, which were mainly governed by religion and agriculture. In modern times, media and migration play important roles in food selection and consumption patterns. Besides these, several other factors that undoubtedly affect our food choices. These factors can be grouped under following categories depicted in Figure 1.3.
Biological factors determine individual variations in food choices. Hunger, appetite and taste are biological determinants of food choice that vary widely in different age groups. Choices are influenced by physiological conditions and gender. Biological factors influencing food choices are as follows:
Age and Gender
Age and gender determine food preferences. With age, taste and nutritional needs may vary. Many young children like sweets and elders may prefer bitter and bland foods. Girls may choose lighter fancy delicacies while boys may go for rich sumptuous meals. During each life stage, an individual makes or is required to make food choices as per his/her physical, physiological and psychological conditions. Children generally imitate adults and their food intakes especially among young children are controlled by their parents and older persons. Adolescents try new foods and their choices are often influenced by body image, their peer group and media. Food choices of the elderly are largely determined by the health condition, socioeconomic conditions as well as availability of food. Eating problems may stem from loneliness, a lack of desire or ability to cook, financial worries or physical problems.
Social support can have a beneficial effect on food choices and facilitate adoption of healthy dietary habits. Social support from within the household and from co-workers has been found to be positively associated with improvements in fruit and vegetable consumption and with the preparative stage of shaping eating habits in childhood. Social support may enhance health promotion through fostering a sense of group belonging and help people to be more competent and self-efficacious.
As the person passes through different stages of the life cycle, food choices vary and food choices tend to change temporarily under certain physiological conditions like pregnancy and lactation as well as during sickness. These are vulnerable periods of life when requirements for nutrients are greater, thus food choices may be influenced by the body's needs. Pregnant women are given more food to cater to the needs of the growing fetus and in some cultures, lactating mothers are given galactogogues to increase milk output.
There are people who may be allergic to some foods and others who may not be able to tolerate specific foods. For example, some babies may have lactose intolerance and cannot digest milk or milk products. Often during illness, there is lack of appetite and taste is affected, which in turn may alter food choices. Even presence/absence of teeth determine the choice of foods in terms of texture.
Our physiological needs are the basic determinants of food choices that can make or mar health. Sickness often necessitates modifications in food and those who do not alter their selection of food can delay healing. In some health conditions, certain foods are restricted or specifically included, e.g. a diabetic person is asked to refrain from sweets and a person with hypertension (high blood pressure) is asked to avoid pickles/papads/sauces because of their high sodium content. A hungry person may make a different food choice than a person who has finished his/her meal. Hunger or loss of appetite can affect the choice of food. During depression, stress and anxiety, some individuals may experience cravings for certain foods whereas some others may not eat or dislike certain foods. Cravings are in general for sweets, alcoholic beverages, chocolates and junk food that can lead to obesity and other health problems.
People living in different geographical locations have different food choices. These are largely associated with the agro-climatic conditions. Climate not only affects the cultivation of food crops but also post-harvest handling and storage. Several environmental factors work together:
Demography and Family Structure
Demography is the scientific study of the population in terms of its size and composition, pattern of living, fertility, migration, literacy rate, mortality and morbidity in a given geographical location. Nuclear families may have different kinds of food choices compared to traditional joint families where more than one generation may live together. Family structure and daily living habits play a significant role in food selection. Older persons may like to have simple basic meals whereas youngsters prefer more zesty foods like noodles, pizza, carbonated soft drinks, cakes, etc. People living alone often compromise with one dish meals like sandwiches or roti.
Besides family composition, the type of dwelling also determines the food choice. People staying in concrete houses may have elaborate, varied cuisines owing to better cooking and storage facilities. Consumption of processed, ready-to-eat foods is also common and they can also store drinking water, food and beverages for later use. In contrast, for people living in temporary dwellings such as in rural and slums areas and refugee shelters, limited resources limit the food choices.
Climate and Season
Climate determines the season and crop cultivation varies with season. In India, there are mainly two crops depending upon the season, i.e. “rabi” crop and ‘kharif’ crop. In Rabi or “winter crop” the seeds are sown in October/November and the crops are harvested in March/April. Rabi crops are wheat, grams, barley; potato, etc. ‘Kharif’ or summer season crop starts from June/July and lasts until September/October. Rice, maize, groundnut, cotton, pulses, jowar, etc. are cultivated in this season. Staple food crops are usually cultivated seasonally or once a year but are used throughout the year. Sometimes a third crop called ‘zayad’ is also considered, in which fruits and vegetables are generally grown in summer. It has been suggested that foods contain maximum nutrients when freshly harvested. Traditionally in India, foods are chosen in accordance with the season. It is believed that consumption of off season foods may harm the body and increase risk of diseases, whereas consuming seasonal foods confer maximum health benefits.
Crops undergo various environmental stresses like rain, drought, and insect pests. Further, dramatic changes in climate may seriously affect food security and modify food choices. Droughts, famines and heavy rainfall may sweep away the crop and affect food supplies, compromising food availability and choice. On the other hand, seasonal surpluses increase availability, cost and hence consumption pattern. Cottage industries and food industries can transform the raw food material into totally new products that can help increase food availability and variety even during off season. However, accessibility to food in cities is not largely dependent on seasons, as it is in rural areas.
On a daily basis, people depend on locally available foods. Food choices of people residing in hilly areas are different from people from coastal areas. Food grown in forests, hills, valleys, land pastures, dry land, and coastal areas are different that naturally affects the food choices of the residents and their cuisines. People in hilly areas usually select specific berries, fruits, leaves and spices whereas people from coastal areas may prefer fish and sea foods. Kashmiris may select “yakhini” and Goans may like fish curry. Walnuts are cultivated in Jammu and Kashmir and cashew nuts in Goa. Coconut, banana and tamarind may be integral ingredients of food in South India as they are cultivated there, whereas rajma, black gram (udad), ‘makki ki roti’, ‘chhole bhature’, ‘kachori’, ‘samosa’, etc. are popular in North India.
Transport, geographical location, availability of vehicles and fuel determine the cost of food and hence food choice. Food is transported from one place to another, from region to region and now from nation to nation. Transport facilities have increased the accessibility of wide variety of foods for most people. However, even today, people living in remote areas have limited food choices as they do not have means of transport. Periodically, they go to nearby markets and procure food materials for several days or months. Women, children, elders and handicapped persons may not be able to go out alone because of their age, gender, social and physical limitations. Hence, they are dependent on others for transport and their food choices may be limited. Food choice for some people is determined by the food available at home or in nearby shops or markets. Famines, droughts, heavy rainfall, cyclones, road blockages due to bad weather and transport strikes greatly affect transport and hence the food supply. If such conditions continue for a prolonged period of time, food choices may be considerably limited. On the contrary, in large cities and metros, those who own a vehicle or know driving, may frequent restaurants or food courts and tend to consume snacks or meals whether they are hungry or not, sometimes just for fun. The latter practice is not desirable since it can adversely affect health.
There has been tremendous advancement in cultivation practices, post-harvest systems, food product development, food preservation techniques, food packaging, food delivery system and the equipment used in food preparation like microwaves. These changes have influenced every aspect of our life including our food choices. Food manufacturers are able to use several technologies to satisfy the consumer. Fast-paced lifestyle and consequent lack of time for cooking especially in urban areas, has gradually led to a shift from consumption of primarily home-cooked foods to an increasing reliance on ready-to-eat, ready-to-cook, convenience and processed foods. In addition, better technology has made it possible to prolong shelf life of foods, making it easier to obtain seasonal fruits and vegetables, for much longer periods and to reach such produce to far-off, distant places. Thus, home-cooked food is gradually being replaced by food prepared commercially and delivered to the home. The market is flooded with ready-to-eat, ready-to-cook, health foods, dietetic foods, microwaveable meals, chilled and frozen foods, fast foods to fulfill the needs and desires of consumers especially in urban areas.
Urbanization implies more concrete buildings, better transport and communication, better opportunities for education and earning and to avail wide variety of food and food products even outside the home. However, there is less agricultural land to grow fresh foods locally and urban people depend on market supply of food. Urbanization tends to change the socio- economic status and food availability, accessibility and affordability and thereby food choices. It has brought sea changes in interest, aptitude, attitude of the people towards cooking and eating. The availability of food processing, food storage appliances and food delivery systems has changed selection of food preparations.
Women who were previously, primarily responsible for providing (cooking, etc.) food to the family members, now also go out to work. There are more nuclear families and persons living alone. People face time constraints and sometimes lack the desire to cook, thus use of convenience foods and eating out is increasing. Canteens in schools, workplaces and vending machines have influenced people's choices. People tend to select food items that do not require much processing/cooking without compromising the taste.
Food culture is based on traditional beliefs, folklore associated with food and religious rituals. In every culture and religion, there are restrictions and some foods may even be forbidden. Some foods are specifically prescribed and are linked with festive occasions like Diwali or physiological requirements like pregnancy. Culture shapes our food choice, pattern of cooking, eating and serving. People can easily change their speech or dress code and imitate other cultures, but a food choice that is born out of culture and tradition is more difficult to change. Culture regulates the food habits that tend to remain stable through generations. The following factors affect food selection:
Food cultures evolved out of agriculture practices and production, religious practices, type of family structure and socioeconomic status. In the past, people blindly followed them out of fear of God's fury or ignorance, often without a rational basis. Friends, neighbors and elder women in the family often dictated food choices to be followed in one's life and the entire family.
Man has an inherent desire to be accepted and appreciated in a given social group. Food is a means of communication, a symbol of status and pride. There is hardly any social meeting or gathering or any occasion, where food and drink are not used to indicate hospitality and served as a token of friendliness and social warmth. Conversation about food also adds knowledge about several issues and can influence eating habits, sometimes favorably but not always. During childhood and adolescence, peer groups influence most food choices.
Many Hindus frown at meat consumption, which is permitted in Islam and Christianity. Some religions permit occasional consumption of fish, poultry and mutton but forbid beef because the cow is considered sacred. Milk and milk products are also animal products but they are consumed as they do not involve killing and support growth of the human body rather than causing harm. Most vegetarians also favor ‘ahimsa’ and from the nutritional perspective, research data suggest that animal foods may not be always healthy. Serving good food and serving the head of the family first is customary in many cultures without looking into the needs of others in the family or considering whether they are hungry.
Culture determines the approved pattern of selection, preparation and serving of food. In South India, the main course consists of rice, sambar, vegetable, pickle and buttermilk, served on a plantain leaf and eaten by hand. However, in North India, people prefer to eat chapattis or rotis with dal and ‘sabji’ and sweets may be eaten with the meal. The new generation is undergoing a phase of changing food habits out of necessity or desire to try new foods and be innovative. Often people of one culture migrate from one place to another, where the culture is different. Migration and the need for survival and/or social acceptance have made people modify their dietary habits.
Media, Marketing and Advertisements
Food choice is remarkably influenced by advertisements. Television is a strong medium that influences food choices. Many foods are promoted through print/electronic media, exhibitions, home visits, and distribution of free samples, etc. People, particularly children may blindly trust the information that is given and select a particular brand without knowing its true worth. Diverse messages, tall health claims and nutritional labels are meant for consumers but some of these can be fads or quackery. However, media and marketing are very powerful tools if they are used for promoting health education and creating awareness about “healthier” food choices. Simple, actionable and accurate messages that the public can readily understand and incorporate into everyday lives, can help people have a clear idea about the quality, cost and use so that they can make informed and healthier choices about foods.
Personal choice wins over all sociocultural and environmental barriers. A person may travel long distance just to eat food of his desired choice to satisfy the sensory appeal. Quite often, a person is not aware of his own nutritional needs and makes wrong food choices that are based on taste, appearance, cravings, availability and easily get swayed by peer pressure and media. Literacy level and occupational needs also affect food choices. The following factors affect personal food choices:
Education and Knowledge
Education has been found to influence dietary behavior during adulthood. In young persons, nutrition knowledge may not influence dietary habits much but among adults and older individuals, it has shown an impact. Information on nutrition disseminated through different sources can be understood and promote adoption of good dietary practices.
Household/family income, family size and cost of food have always been important determinants of food choices in almost every household. In families, which lack financial resources, food choices are generally limited to staple foods and do not allow the family to include a variety of foods in the diet. Thus, their diets may be unbalanced and inadequate in several important nutrients because of non-inclusion of valuable nutritious foods like milk and milk products, eggs, meat, vegetables and fruits.
Food price determines food selection and rise in prices of commonly used food commodities like cereals, flours, sugar, milk, vegetables and oils seriously affects the food budget. It especially affects the poor and even the rich today. On the other hand, people from higher income group can afford and may consume foods like aerated soft drinks, ice creams, chocolates, imported foods, etc. Many of these foods contain too much fat and/or sugar and less of valuable nutrients. Eating too much of these can have adverse influence on health. Availability of financial resources does not guarantee healthy food choices.
People are more often concerned about satisfying their sense. ‘Taste’ is a major factor that determines whether a person accepts or rejects the food. Smell, appearance, flavor and texture of food also influence food choices significantly. From an early age itself, taste and familiarity are important. The pleasure someone experiences with a particular food is proportional to palatability. Sweet and high-fat foods have an undeniable sensory appeal and hence may often be preferred more than more-nutritious foodstuffs.
Eating Away From Home
Eating behaviors and dietary quality are influenced by the places where food is consumed—at home, school, or away from home at restaurants and fast food establishments. Frequently eating out may negatively affect the nutritional quality of the diet as well as increase the risk of food infection/poisoning and related diseases. Eating out is generally done for enjoyment but most of time, the food items selected, are rich in energy, fat and sugar. Regularly eating out, needs rethinking from health point of view, since hygiene and nutrition are of prime importance.
Emotions and Stress
Emotions are deep seated in the brain. One can recall events/incidents or experiences associated with a particular food even after 20–30 years. Stress is a common feature of modern urban life and can modify behavior that affects lifestyle, such as physical activity, smoking as well as consumption of alcohol. Generally happy mood and happy events call for eating food preferably, sweets and other rich food. However, some people indulge in eating anything available when they are anxious/stressed/in a sad mood. Certain foods may contain some specific chemical substances that may trigger mood-regulating hormones. Chocolates and coffee may elevate the mood and people tend to crave.
Food choices and food intake are influenced by myriad factors that critically affect the nutrition and health of the person. When the diet supplies adequate amounts of all necessary nutrients and the individual is healthy, the person is well-nourished. A well-nourished person is able to obtain and utilize foods at all levels and conditions and still maintain the health in different phases of life. However, intakes that do not match the body's requirements result in poor nutrition.
GOOD NUTRITION AND MALNUTRITION
Good nutrition implies optimal intake of energy and other nutrients in accordance with the individual's requirements. Such a person is said to be well nourished. The person is healthy, cheerful and can perform to a satisfactory level. Good nutrition helps to achieve good health.
However, across the world, we find that there are masses of people who do not have adequate food or even two meals in a day. There are many whose diets lack one or more nutrient. Conversely there are a large number who consume too much food or who consume certain foods and/or nutrients in amounts that are more than their bodies require. All of these situations have adverse impacts on the human body and health, resulting in malnutrition. Table 1.1 indicates the characteristics associated with good and poor nutrition.
Malnutrition is rampant throughout the world. It inflicts avoidable suffering on millions of people, particularly children and women resulting in poor health and quality of life of the malnourished and hungry population. Malnutrition is an undesirable state of health resulting from imbalance in nutrient intake (deficient or excess amount) and /or nutrient utilization in relation to the requirements of the individuals. It can be considered as a pathological problem since it adversely affects metabolic and cellular functioning and causes clinical symptoms.
The World Health Organization (WHO) defines malnutrition as "the cellular imbalance between the supply of nutrients and energy and the body's demand for them to ensure growth, maintenance, and specific functions."The term “malnutrition” is often used interchangeably with the term “undernutrition”. However, in reality it refers not only to deficiencies but also to excess or imbalance of energy, protein and other essential nutrients. Technically, there are two types of malnutrition:
Undernutrition: Because of deficiency of energy and nutrients.
Overnutrition: Because of excessive intake of energy and nutrients.
Undernutrition encompasses both protein-energy malnutrition and micronutrient deficiencies. It occurs when, over a considerable period of time, food intake in terms of quantity and nutritional quality is not adequate enough to meet the dietary and nutritional requirements.
In some cases, food intake may be sufficient but a person can have problems with digestion and absorption of food or utilization/metabolism in the body may be disturbed. Whatever the cause, the result is low body weight for age and deficiency disease(s) of minerals and vitamins. In children, undernutrition is measured in terms of underweight, stunting and wasting (Figure 1.4).
Underweight implies low body weight for a given age compared to reference standards. It reflects body size and the level of food and nutrient intake as well as the presence of disease. It is a sensitive measure and reflects acute changes in body weight over a short duration.
Stunted means low height for the age compared to reference standards. It signifies deprivation of adequate energy and nutrients for a long period of time, i.e. prolonged undernutrition. In developing countries, such as India, stunting can be a result of undernutrition from fetal stage. It is not affected by immediate circumstances.
A low body weight for given height compared to reference standards is indicative of wasting.
For adults, undernutrition or overnutrition is assessed in terms Body Mass Index (BMI) and BMI below 18.5 indicates undernourishment and if the BMI is below 16, the individual is said to be severely undernourished. Another term used is Chronic Energy Deficiency (CED).
Prevalence of Undernutrition
According to the National Family Health Survey (NFHS III- 2006), 47.0% children were underweight; 45.5% stunted and 15.5% wasted and the prevalence of chronic energy deficiency was 33% in women and 30% in men. In 21 out of 92 countries, about 10% of wasting among children requires immediate attention, because they are at high risk of death. In South Asia, wasting is about 19%, which is alarmingly high. Stunting is a much bigger problem because nearly one-third of less than 5-year-old children in developing countries are stunted. There is hardly any gender difference for underweight but child population from rural areas, urban slums and economically poor households have a higher percentage of undernourished children (UNICEF, 2012).
Groups Vulnerable to Undernutrition
- About 0–6 years of children especially infants in the first 18–24 months of life
- Adolescent girls
- Pregnant and lactating women
- Aged population.
Reasons for Undernutrition
Undernutrition signifies inadequate supply of nutrients to the cells for optimal functioning of the body. Poverty and hunger (lack of nutrition not just food alone) are leading causes of undernutrition that result in low intake of food, inefficient utilization of nutrients or loss of nutrients from the body (Figure 1.5).
Causes of undernutrition include economic and many environmental factors. Various biological, social, cultural, ecological, environmental, economic and political factors are directly or indirectly responsible for omnipresent malnutrition and there are many confounding factors that play a significant role (Table 1.2).
Some of the factors are specific in different life stages. Infants, children and adolescents are undernourished due to poor sanitation and hygiene, inadequate availability of water, infections and illness, inadequate parenting (care) and poor feeding practices. During pregnancy, increased nutrient demands vis-a-vis requirements increases risk of undernutrition. Adults and elders are at risk of being undernourished due to inadequate food and nutrient intake for various social, economic and personal reasons.
Consequences of Undernutrition
Malnutrition affects every facet of life and people of all age groups living in all geographic areas. Millions of newborns, young and old children, youth, adults, pregnant and lactating women, and senior citizens, even sick and hospitalized people are victims of malnutrition. Malnutrition adversely influences individuals, families, communities and nations. There is perhaps no harm in being lean or short, if one is healthy. These characteristics in many are genetically determined. Undernutrition during childhood reduces the chances of normal physical and mental development. Worldwide, deficiencies of vitamin A, iodine, iron and zinc are prevalent and contribute to the high rates of morbidity and mortality particularly among infants and young children. Micronutrient deficiencies are also termed as “hidden hunger”. The effects of undernutrition/malnutrition are shown in Figure 1.6.
Excessive intake of energy and nutrients for a prolonged period of time may result in overnutrition and the risk of overnutrition is much higher when the physical activity is also less. Overnutrition is characterized by overweight and poor body stature, lack of stamina and impaired functioning of body. BMI or Body Mass Index is used to determine the level of overweight and obesity (See Chapter 5).
Overweight and obesity are associated with excess accumulation of fat in adipose tissue. Fat deposition varies with age, gender and different parts of the body. In some persons, fat is deposited on abdominal area that is referred as abdominal obesity. Obesity is known to alter the metabolic functions and increases risk of various morbidities. Obesity is discussed in detail in Chapter 12. Vulnerable age groups for overweight and obesity include school age children, adolescents and adults.
Strategies to Combat Malnutrition
All human beings wish to be healthy and well nourished. Man tries the best possible ways within the given resources. Since the size of population is increasing, the number of malnourished persons in this country is also high. Although the national food production database reflects increased food production and there is progress in reduction of malnutrition, the picture is still dismal. Malnutrition is not restricted to India. It is a global problem, hence for last many decades it has been tackled at all levels but “no one size fits all”. Even today whether it is at the World Health Organization (WHO) or at National Institute of Nutrition (NIN), India, Nobel laureates, professors, scientists, economists and policy makers are trying hard to tackle the problem of malnutrition. Overcoming malnutrition requires tackling following challenges:
- Hunger and food insecurity
- Poor health and disease
- Inequality in gender, socioeconomic status and intra-household food distribution
- Education and status of women in society
- Climate change—affecting natural resources for food and safe drinking water, creating pollution, damaging land for cultivation.
Interventions are required from the macro level (national level) to the micro level (family and individual levels).
Interventions at the family and individual levels:
- Dietary diversification
- Exclusive breastfeeding from 0–6 months of age
- Adequate and timely complementary feeding from 6–24 months
- Adequate hygiene practices at every stage of food handling and eating
- Extra care for infants, adolescents girls and pregnant and lactating women and elders with regard to food behavior
- Nutrition and health education.
Interventions at National level in India:
- Green revolution was one of the major strategies to reduce hunger and death due to grain shortage
- Several nutrition programes and health schemes were launched after Independence
- Establishment of agricultural universities and other universities for higher education, medicine and technology and subsidies to farmers for seeds, fertilizers and pesticides; attention to horticulture, dairy, fish culture
- Improved access to health care services through primary health care centers, hospitals and ICDS anganwadi centers
- Favorable health care facilities—Doctors, trained paramedical staff and availability of medicine and needed infrastructure
- Better sanitation facilities
- Access to safe drinking water
- Improvement in food access and enhancement in household food security through public distribution system and fair price shops.
The World Health Organization (WHO), the apex body on health, states “Health is a state of complete physical, mental and social wellbeing and not merely the absence of disease or infirmity”. Over the years several definitions have been given to reflect different concepts about health. Some of them are briefly discussed herein.
Health is a sum total of the supply and utilization of food and nutrients for the soul, mind and body. Health is a self-promised, self-regulatory and self-practiced phenomenon. “Swastha” in Sanskrit indicates the ‘swa’ and ‘astha.’. ‘Swa’ means self and ‘astha’ denotes faith or commitment. It is a promise given to self to take charge of one's own health. Health resides within one's body, mind and soul and is reflected through physical, physiological, emotional, mental, and spiritual attributes. It is one of the highest pursuits of life and a way of life to achieve its goal. Health can be viewed as an active process used by persons to adapt to his or her environment that is always dynamic and changing. Good health is critical for wellness. Wellness is defined as a dynamic state of health, in which a person progresses toward a higher level of functioning, achieving an optimum balance between internal and external environments. In simpler terms, it is a condition of good physical, mental and emotional health, especially when maintained by an appropriate diet, exercise, and other lifestyle modifications. Lifestyle includes the way of living—self designed and determined daily habits related to eating, exercise, occupation, social life, managing emergencies and still smiling while coping with stresses. Health is influenced by numerous factors:
- Hereditary or genetics: Phenylketonuria is an inborn error of metabolism. Sickle cell anemia is a genetic disorder. Mental retardation and congenital abnormalities in some cases are also inherent problems.
- Age and gender: Youth suffer less health problems while elders are more likely to have health problems especially chronic ones like arthritis.
- Physical condition of the individual: Stature, physical disability, work capacity and body weight are related to health and nutritional status. Disability, smaller body size and reduced work capacity can be caused by poor nutrition during fetal life or later in life.
- Nutrition and food habits: Consuming nutritious, well-balanced diets as per the individual's requirements are important for promoting and maintaining good health as well as preventing problems. Nutrition knowledge, interest and motivation for skillful cooking, support promoting and maintaining good health.
- Personality characteristics: Calmness and confidence are usually observed in healthy persons. Healthy persons are able to cope with every day stresses of life. Persons who do not enjoy good health may feel stressed, some may be depressed, some may respond with anger and aggression.
- Environment: Housing, soil, climate, waste and sewage disposal, environmental pollution presence of plants, trees, animals and the sociocultural features of the region where a person lives are important factors. Markets, transport and storage facilities for food, also affect health.
- Lifestyle: Cultural and behavioral pattern, sleep, physical activity, smoking and use and abuse of alcohol, narcotic drugs all influence health.
- Economic status: Food prices, income, literacy, occupation, purchasing power play important roles in health promotion and protection.
- Social status: Residence and country of origin and social network and social integration are some issues.
- Access to and availability of health services: Availability of and access to provision of safe water and other preventive measures, primary health care, immunization services and hospitals are important for preventing diseases as well as maintaining and promoting health.
Good nutrition has a preventive role and promotes good health and wellbeing in multidimensional ways:
- To maintain body weight appropriate for height, age and sex
- To maintain muscle mass
- To be energetic and active
- To provide resistance to infection
- To help cope with stress
- To decreases risk of disability
- To prevent illness
- To alter the course of illness (reduce the duration)
- To increase longevity
- To Perform better and increase productivity
- To improve the social and economic status
- To improve the quality of life.
- Define food as per FSSA (2006).
- What are the functions of food?
- Which other areas of science are linked with nutrition?
- What is the difference between macro and micronutrients?
- How do you perceive wellness?
- What is malnutrition?
- Which factors affect malnutrition?
- What is the current status of overnutrition and undernutrition in India?
- Suggest some ways to combat malnutrition in your local area.
- What do you understand by dual burden of malnutrition?
- Observe the current food choices in your neighboring area and which factors affect their choices?
- Observe the people (50) who are undernourished or overnourished in your neighboring area, identify their characteristics and differentiate between them.
- Design some strategies and make a presentation (verbal/PPT, etc.) to improve their health and wellbeing?
- Behrman JR, Alderman H, Hoddinott J. Hunger and Malnutrition – Challenges and Opportunities – Perspective Paper, Copenhagen Consensus. 2004.
- Cox DN, Anderson AS. Food choice. In: Public Health Nutrition, Gibney MJ, Margetts BM, Kearney JM. and Arab L (Eds), Blackwell Publishing Delhi. The Nutrition Society. 2005.pp.144–65.
- Deaton A, Dreze J. Nutrition in India: Fact and Interpretation, Working paper No 170, Center of Developmental Economics, New Delhi, School of Economics. 2008.
- Eastwood M. Principle of Human Nutrition (2nd edition). Blackwell Publishing, Edinburgh. 2003.
- FAO. The State of Food Insecurity. United Nations Food Agriculture Organization. 2006;1–40. 12 Aug. 2007, ftp://ftp.fao.org/docrep/fao/009/a0750e/a0750e00.pdf
- Food and Agriculture Organization (FAO) of United Nation. The State of Food Insecurity in the World- Economic crisis- Impacts and lesson learned. 2009.pp.8–12. ftp://ftp.fao.org/docrep/fao/012/i0876e/i0876e.pdf
- http://www.childinfo.org/undernutrition_status.html (2011 by UNICEF)
- National Family Health Survey in collaboration with International Institute of Population Sciences and Ministry of Health and Family Welfare, Government of India. 2006.
- Nutrition Foundation of India (2005) Twenty Five Years Report. 1980–2005.
- Paul I, Turner RE, Ross D. Nutrition (3rd edition). American Dietetic Association, Jones and Bartlett Publishers. Boston. 2007.
- Swaminathan MS. Mission 2007: A Nutrition Secure India, Paper presentation at Silver Jubilee Symposium (Nov 2004) Towards National Nutrition Security: 2004.
- Tangeranmaum S. Economic factors influencing food choice. In: Food Consumers by Riston C, Goften L, McKenzie J. (Eds) John Wiley and Sons, New York. 1986. pp.44–60.
- Vorster HH, Hautvast J. Introduction to human nutrition: A global perspective on food and nutrition. In: Introduction to Human Nutrition Eds: Gibney MJ, Vorster HH Kok, FJ. Blackwell Science Ltd., Oxford. 2002.pp.1–11.
- Wilson ED, Fisher KH, Fuqua ME. Principles of Nutrition. Wiley Eastern Private Limited, New Delhi. 1965.