Introduction to human nutrition

Hafiza Madiha Jaffar

1. INTRODUCTION TO HUMAN NUTRITION Presented By: Ms. Hafiza Madiha Jaffar Clinical Nutritionist

2. DEFINITIONS Food: any substance, solid or liquid, that contains nutrients, which meets the needs for energy, building, regulation and protection of the body.

3. CLASSIFICATION Classification by origin: - Foods of animal origin Foods of vegetable origin Classification by chemical composition: Proteins Fats Carbohydrates Vitamins Minerals

4. DEFINITIONS Nutrition is the study of nutrients in food, and the relationship between diet, health, and disease. Is the process of consuming, absorbing and using nutrients needed by the body for growth, development and maintenance of life. Human nutrition  deals with the provision of essential nutrients in food that are necessary to support human life and health. Nutrition science deals with the role of food (dietary inputs) in the maintenance of life.

5. DEFINITIONS Diet refers to whatever you eat and drink each day. Balanced diet : contains all the nutrients in the correct amount for the needs of the body. Recommended dietary allowance (RDA): the amount of the nutrient we should eat each day Deficiency disease: ill effects that are caused by lack of the nutrient

6. NUTRIENTS Nutrient is any substance which can be digested and used by the body. Or Organic and inorganic complexes contained in food are called nutrients. They are broadly divided in to:

7. TYPES OF NUTRIENTS Macronutrients: Nutrients required in relatively large amounts. Provide energy to our bodies Carbohydrates, fats and oils, proteins Micronutrients: Nutrients required in smaller amounts. Vitamins and minerals

8. ENERGY FROM NUTRIENTS/ DAILY CALORIC INTAKE Your body’s energy needs are measured in calories. A calorie is the amount of energy needed to raise the temperature of 1 kilogram or water 1 degree Celsius. You expend calories with everything you do. On food labels “calorie” refers to kilocalories.

9. HOW MANY CALORIES SHOULD I EAT?

10. WHY IS IT IMPORTANT TO EAT HEALTHY? Best way to live a healthy life is to eat a balanced diet To provide nutrients that your body needs to function like provide energy, building the body and regulate activities of the body. To give you more energy and alertness throughout the day To prevent future disease and sickness like Diabetes, obesity and cancer etc.

11. SCOPE OF FOOD & NUTRITION FOOD CHEMIST SPORTS NUTRITIONIST

12. MALNUTRITION Health as the ‘state of complete physical, mental and social well-being and not merely the absence of disease’ Malnutrition is defined as "lack of proper nutrition, caused by not having enough to eat, not eating enough of the right things, or being unable to use the food that one does eat". or imbalance of nutrients in the diet. It includes undernutrition and overnutrition. Undernutrition is a state of an insufficient supply of essential nutrients. Overnutrition refers to an excessive intake of one or more nutrients, which creates a stress in the bodily function.

13. STEPS OF NUTRITION The use of food in the body involves three processes — ingestion, digestion, absorption and utilization of nutrients in the body. Digestion is the process, which releases many nutrients in the forms the body can use, by breaking up food in the intestinal tract. e.g. carbohydrate into glucose, proteins into amino acid and lipids into fatty acid Absorption is the process which carries these nutrients into the circulation system and delivers them to the cell. Utilization. Cell is the functional unit of life. Hence many the chemical reactions in the cell utilize the nutrients absorbed to produce materials needed for our existence.

14. STEPS OF NUTRITION

15. DIFFERENCES BETWEEN MACRO-NUTRIENTS AND MICRO-NUTRIENTS S.N. Difference on the basis of Macro-nutrients Micro-nutrients 1.        Requirement Macro-nutrients are required in larger amount/quantity on daily basis Micro-nutrients are required in small or tiny amount/quantity on daily basis 2.        Function Macro-nutrients is essential for growth, repair and develop new tissues (carbohydrates), maintain body temperature (fats), conduct nerve impulses, and regulate life process. Micro-nutrients support macro-nutrients to carry out bodily functions. They are also an essential component for building healthy brain, body and bones. 3.        Benefits/advantages ·  Macro-nutrients contribute to the bulk energy needed for the metabolic system. ·  Macro-nutrients provide calories that gives energy to the body ·   Micro-nutrients contribute to body growth and disease prevention. ·   Micro-nutrients comprises of high volume of antioxidants which protects the body against various diseases 4.        Role Macro-nutrients plays a vital role in the construction of body composition. Micro-nutrients do not have any role in the construction of body composition. 5.        Concentration Macro-nutrients are available in high concentration inside the body. Micro-nutrients are present in minute concentration inside the body.

16. 6.        Composition/known as Macro-nutrients are also called as major elements. Micro-nutrients are also called trace elements. 7.        Food composition Cereals, legumes, meat, fish, yams, potatoes, nuts, oilseeds are rich in macro-nutrients. Mainly vegetables, fruits, eggs, green leafy vegetables, fermented foods are rich in micro-nutrients. 8.        Types and examples There are mainly three macro-nutrients required by the body; carbohydrate, protein and fats Different types of micro-nutrients required by the body include vitamins, minerals and trace elements.  Examples: iron, magnesium, calcium, phosphorus, zinc etc. 9.        Quantity Macro-nutrients are divided into two classes: Primary and Secondary, as they are required in large quantities. Micro-nutrients are not classified in different types, as it is required in trace amount. 1 .    Toxicity Macro-nutrients are normally not toxic to the cell if they are present in comparatively higher concentration than in the normal level. Micro-nutrients are toxic if present hugely in the cell than the required amount. 1 1 .    Excessive ingestion Excessive intake of micro-nutrients leads to obesity and diabetes. Excessive consumption of micro-nutrients leads to suppressing immune function.

17. 1 2 .    Consequences of deficiency Deficiency of macro-nutrients causes Protein Energy Malnutrition (PEM), Kwashiorkor, marasmus etc.   Deficiency of micro-nutrients causes different diseases like night blindness, beriberi, scurvy, goiter etc.   1 3 .    Consequences of overdose Overdose of macro-nutrients causes obesity, heart diseases, diabetes and other metabolic syndromes Overdose of micro-nutrients may harm specific organs of the body. E.g.: overdose of vitamins affect liver 1 4 .    Daily recommended requirements ·  From carbohydrates : 55–75% of total energy ·  From protein : 15-20% of total energy or 1g/kg body weight per day ·  From fats : 20-35% of total energy ·  From monounsaturated fats : 20% of total energy ·  From polyunsaturated fats : 10% of total energy ·  From saturated fats : 7% of total energy   ·      Vitamin A – 700 µg ·      Vitamin B12 – 2.4 mg ·      Vitamin E – 15 mg ·      Vitamin C – 75 mg ·      Thiamine – 1 mg ·      Riboflavin – 1.1 mg ·      Niacin – 14 mg ·      Folate – 400 mg ·      Iron – 18 mg ·      Selenium – 55 mg ·      Calcium – 1000 mg

18. OVERVIEW OF MACRONUTRIENTS

19. CARBOHYDRATES They are required for energy and provide body’s main source of energy; they form the major part of stored food in the body for later use of energy and exist in three form: Sugar Starch Fiber The brain works entirely on glucose alone. When in excess, it is stored in the liver as Glycogen. Carbohydrates are also important for fat oxidation and can also be converted into protein.

20. RECOMMENDED ALLOWANCE Sedentary Individuals: 40-50% of your total daily calories should be carbohydrates Exercises Regularly: 60% of your total daily calories should be carbohydrates Athletes or persons involved in heavy training: 70% of your total daily calories should be carbohydrates (3.5-4.5 grams of carbohydrate per pound of body weight) NOTE: 1 gram of carbohydrate = 4 Calories

21. Food Sources Grains (choose mostly whole grains for added benefits) Dairy (choose low-fat or non-fat most often) Fruit (choose whole fruits more often than fruit juices)

22. PROTEINS They provide amino acids and make up most of the cell structure including the cell membrane. They are the last to be used of all macronutrients. In cases of extreme starvation/ hunger, the muscles in the body, that are made up of proteins, are used to provide energy. This is called muscle wasting .

23. RECOMMENDED DAILY ALLOWANCE Sedentary Individuals: 0.36 grams of protein per pound of body weight Active: 0.45-0.68 grams of protein per pound of body weight Competitive Athlete: 0.54-0.82 grams of protein per pound of body weight Teenage Athlete: 0.82-0.91 grams of protein per pound of body weight Body Builder: 0.64-0.91 grams of protein per pound of body weight NOTE: 1 gram of protein = 4 Calories

24. FOOD SOURCES Legumes (beans) Lentils Peanuts and nuts Whole grains (quinoa, oats, brown rice) Seeds Meat alternative products Some vegetables Animal sources

25. FATS Fats are used in making steroids and hormones and serve as solvents for hormones and fat-soluble vitamins. Fats have the highest caloric content and provide the largest amount of energy when burnt. Extra fat is stored in adipose tissue and is burnt when the body has run out of carbohydrates.

26. FATS Role in the Body Energy reserve Protects vital organs Insulation Transport fat soluble vitamins Recommended Allowance 20-35% of your total daily calories should come from fat Less than 10% of total daily calories should come from Saturated Fat (coconut oil, butter, cream cheese, full fat dairy products) NOTE : 1 gram of fat = 9 Calories

27. FOOD SOURCES Oils Nuts Seeds Meat, fish, dairy

28. EFFECTIVE NUTRITIONAL PLAN Breakfast is the most important meal of the day. Attempt to eat 4-6 meals per day. Minimum of 8 glasses of water per day. Attempt to consume carbohydrates, proteins, and fats in every meal. Vegetables are the best source of vitamins and minerals. Read labels and understand serving sizes. Supplements should be used as supplements.

29. REFERENCES https://www.publichealthnotes.com/15-differences-between-macro-nutrients-and-micro-nutrients/ http://mynutrition.wsu.edu/nutrition-basics#carbo