MODULE 1 MANS FOOD NOTESHealthy People 2010Prior to this course, you may not have thought much about nutrition and health, but what you are doing today may influence how you feel 30 years from now.One of the greatest things about studying food and nutrition is that it is a subject that applies to everyone, from the newborn baby to his or her grandparents. Everyone has to eat—it is essential to life and well-being.The U.S. Surgeon General has called for a nationwide health improvementprogram, called Healthy People 2010, which contains a set of health objectives for the U.S. to achieve over the first decade of this century. Two of the main goals are:• To help all Americans increase their life expectancy and improve their quality of life.• To eliminate health disparities among different segments of the population.Objectives for Healthy People 2020 are being developed.As you complete this course, think about how the nutritional choices you made in 2010 might differ from the choices you make in 2020.Leading Causes of Illness and Death in the U.S.Many people study nutrition in order to understand how lifestyles and habits help minimize the risks of disease.The leading causes of illness and death in the U.S. today are heart diseases, cancers, and strokes. Diet is a risk factor for each of these ailments. The nutritional and health habits you practice today may influence what happens to your health in the future.On a world-wide basis, estimates indicate 3 to 4 million cases of cancer per year could be prevented by improving diet and exercise alone. Reportsin the media suggest that pesticides, cell phones, and radiation are main causes of cancer, but only 3% to 4% of cancers are traceable to these factors. In comparison, 30% to 40% of all cancers may be attributed to dietand lifestyle.Modifying lifestyles and habits helps minimize the risk of these diseases. By understanding nutrition, health concepts, and controversies, you will have the necessary vocabulary to evaluate and discuss nutrition with friends, family, and associates.What is Nutrition?Knowing what nutrition is and how to assess nutritional choices is important in assessing whether your habits are healthy.The term "nutrition" has multiple definitions. It can refer to the process a living organism uses to assimilate food, or the science that deals with food and nourishment. In this course, nutrition is:• the qualitative science that describes which chemicals the body needs for optimal health and well-being, and• the quantitative science that indicates how much of each chemical is needed by the body.In other words, the study of nutrition considers which chemicals, and how much, are needed to support and sustain a healthy body.Nutrition must also define how these chemicals are ingested, digested, absorbed, transported, metabolized, and eliminated. Studying this information about the chemicals helps you understand how much is needed; how much is metabolized or broken down; and where it goes, not only in the body, but on the molecular level as well (that is, the cell).Qualitative Science of Nutrition—NutrientsNutrients are substances which are essential for the maintenance, repair, growth, and reproduction of all our body tissues. Nutrients are divided into six categories.The basic nutrients our foods contain are carbohydrates, fats, proteins, and water. These nutrients are called macronutrients because they make up the largest portion of any foodstuff, by weight.Our foods also contain two micronutrients—vitamins and minerals—which make up a small percentage of our food, by weight.• Carbohydrates – Our body’s most efficient source of energy and an essential component in the production of many structural and functional materials.• Fats – Divided in two categories: saturated, which are solid at room temperature and found mostly in animal tissues, and unsaturated, which are liquid and found mostly in plant tissues.• Proteins – The building blocks that make up this nutrient are called amino acids. This nutrient is found in all foods derived from animals and plants.• Water – The environment in which cells live; it is approximately 60 percent of our body weight.• Vitamins – Organic compounds that are synthesized, for the most part, only by plants and bacteria; our supply comes from plant foods and our own bowel bacteria.• Minerals – These nutrients come from inorganic matter, primarily the earth; some are important in our structural material, for instance, our bones and teeth.Function of NutrientsThere are three types of functions that nutrients perform:• Building blocks: for example, protein is used for muscle, calcium is used in the skeleton system, etc.• Energy: for the body and cells• Maintenance/regulation: help maintain homeostasis*.*Homeostasis is the ability or tendency of an organism or a cell to maintain internal equilibrium by adjusting its physiological processes.Different nutrients have different roles in maintaining a healthy body. For example:• Proteins do all three functions. They provide building blocks (muscle), anenergy source and maintenance/regulation (hormones/enzymes).• Carbohydrates perform one function: to supply energy for the body.• Fats, like proteins, are involved in all three functions (building blocks (cellmembranes), energy source, and maintenance/regulation (steroid hormones).• Water participates actively in forming building blocks of cells.• Vitamins only provide maintenance/regulation.• Minerals supply building blocks (calcium and phosphorus for bones and teeth) and maintenance (e.g., zinc is a part of insulin; iron as a part of hemoglobin).The bottom line is that all nutrients have specific roles for optimal health and well-being, and one nutrient simply cannot supply all our nutritional needs. This is why we have to take in foods that supply the six categories of nutrients—because of their different roles.Nutrients in FoodDividing nutrients into six categories is a convenient way to group the chemicals needed for the body. Many chemicals go into making a body healthy; approximately 40 chemicals are required by the body for optimal health and well-being.For most people, these 40 important chemicals are consumed in the form of a multivitamin or by ingesting food.Does your favorite meal provide all the chemicals your body needs? To answer that question, review the number of calories the meal provides in protein, fat, and carbohydrates; these