Chapter 1 Nutrition: Food for Health

Nutrition Terms Nutrition is a science that studies the interactions between living organisms and food. Food provides nutrients and energy. Nutrients are chemical substances in foods that provide energy and structure and help regulate body processes.

How Healthy is the Typical American Diet? Processed and convenience foods are easily obtainable but may not provide necessary nutrients. Processed and convenience foods contain elevated levels of calories, sodium and fat. We don’t eat enough whole grains, vegetables, fruits, seafood, or dairy products.

Nutrition-Related Deaths Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Nutrition Terms Essential Nutrients must be provided in the diet. Fortified foods have nutrients added. Enriched grains have thiamin, riboflavin, niacin, iron and folic acid added. Dietary Supplements contains one or more of the following: vitamins, minerals, plant- derived substances, amino acids, or concentrates or extracts.

Classes of Nutrients: Macronutrients Energy-yielding nutrients include carbohydrates, proteins and fats. Energy-yielding nutrients are also called macronutrients. Macronutrients are needed in the body in large amounts each day.

Classes of Nutrients: Macronutrients Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Classes of Nutrients: Macronutrients Macronutrients provide energy to the body. The amount of energy is measured in kilocalories or kilojoules, depending on the country you are in. 1 kilocalorie = 4.18 kilojoules 4.18 kilojoules = 1 kilocalorie Kilocalorie is abbreviated kcalorie or kcal. Kilojoule is abbreviated kjoule or kJ.

Classes of Nutrients: Macronutrients Carbohydrates Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Classes of Nutrients: Macronutrients Lipids Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Classes of Nutrients: Macronutrients Proteins Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Macronutrient: Carbohydrates Carbohydrates include sugars and starches. Carbohydrates provide 4 kilocalories/gram. Fiber belongs to the category of carbohydrates but does not provide energy.

Copyright © 2013 John Wiley & Sons, Inc. All rights reserved. Classes of Macronutrients: Lipids Lipids are commonly called “fats” or “oils.” Lipids are a concentrated form of energy. Triglyceride is a type of fat that is found abundantly in the body.

Classes of Macronutrients: Lipids Foods high in saturated fatty acids may promote certain diseases. Foods high in unsaturated fatty acids may help to prevent certain diseases. Lipids contain 9 kilocalories/gram.

Categories of Macronutrients: Proteins Proteins are required for growth, maintenance and repair of the body. Proteins can also supply energy. Meat, fish, poultry, dairy products, legumes and grains can provide protein.

Categories of Macronutrients: Proteins Proteins are made up of different combinations of amino acids. Proteins provide 4 kilocalories/gram.

Classes of Nutrients: Micronutrients Micronutrients provide no energy for the body but are necessary for proper functioning of the body. Micronutrients include vitamins and minerals. Micronutrients are very important for good health but are required in small amounts. Micronutrients can be found in most fresh foods.

Classes of Nutrients: Water Water is a macronutrient, meaning that it is required in large amounts. Water does not provide kilocalories. Water makes up approximately 60% of the healthy human body.

Composition of the Human Body Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Functions of Nutrients: Providing Energy Working together, macronutrients and micronutrients help the body to stay healthy. Biochemical reactions in the body help to release the energy contained in carbohydrates, fats and proteins. Energy is used to maintain body functions and fuel physical work. If more energy is consumed than is needed, over time body weight will increase.

Functions of Nutrients: Forming Structures Most of the weight of the body is due to water, fat and protein. Nutrients help to form and maintain the shape and structure of the body. Proteins form ligaments and tendons that hold bones together and attach muscles to bones. At the cellular level, lipids and proteins make up the membranes that surround cells.

Regulating Body Processes All the reactions that occur in the body are called metabolism. The proper regulation of metabolism is called homeostasis. Each nutrient plays a role in helping to maintain homeostasis. Water helps to regulate temperature. Protein, vitamins and minerals help to speed up or slow down metabolic reactions.

Malnutrition Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Overnutrition Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Diet, Genes and Health Nutrigenomics The study of how diet affects genes and how genetic variation can affect the impact of nutrients on health. Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Food Availability Geography Transportation and mobility Available income Food storage and preparation equipment

Cultural and Personal Background Religious dietary laws Ethnic menu preferences Social acceptability Personal preference Psychological and emotional factors Health concerns

Copyright © 2013 John Wiley & Sons, Inc. All rights reserved. FIGURE 7 - The food system

Definition of Adequate Diet Several major conditions define an adequate diet, necessary for an individual to stay active and healthy: · It should provide adequate energy and protein. · It should provide micronutrients (vitamins and minerals) in sufficient quantities to maintain good health · It should be safe and free from contaminants, parasites and toxins which may be injurious to health. · It should be culturally acceptable and, in addition, should satisfy the palate and be capable of providing pleasure to the consumer.

Nutrient Density Nutrient density is a measure of the nutrient a food provides compared to its energy content. Copyright © 2013 John Wiley & Sons, Inc. All rights reserved.

Eat a Variety of Foods No one food provides all necessary nutrients. Selecting a variety of foods helps the body to obtain all necessary nutrients. There are many interactions between foods. Selecting a variety of foods means you will provide the fuel the body needs, even if some of the food interactions are not positive.

Balance Your Choices There is no good food/bad food. Balancing foods allow all foods to fit in a healthy diet. Balance calories in with calories out.

Everything in Moderation Moderation means all types of foods and beverages are okay, as long as they are taken in moderation. Moderation means not consuming too much energy, fat, sugar, sodium or alcohol.

Identifying Reliable Nutrition Information Does the information make sense?  For example, can you really lose forty pounds in one week? What’s the source?  Is it selling something?  Is it someone’s opinion?  Who is a legitimate source of information?  Who will benefit when you purchase this product?

Identifying Reliable Nutrition Information Is it based on good science?  Is the information based on well-designed, accurately-interpreted research studies? Has this product stood the test of time?  Many studies duplicated over a period of time show the same results