Food & Energy

Human Biology & Health Chapter 3.1Pages 68-75

Why We Eat

• Food provides your body with materials for growth, repair and energy

• These materials are called Nutrients• There are 6 kinds of Nutrients:1. Carbohydrat

es2. Fats3. Proteins

4. Vitamins5. Minerals6. Water

Nutrients: Energy

• Carbohydrates and fats provide energy

• Energy is measured in calories: the amount of energy needed to raise the temp of 1g of water by 1⁰C

• A Calorie (capital C) is 1,000 calories.

Nutrients: Energy

• Carbohydrates are a major source of energy and material for cells– One gram of carbs

gives you 4 Calories of energy

• Two categories – Simple and Complex Carbohydrates.

Carbohydrates - SimpleSimple Carbs

• Known as Sugars• Glucose (a sugar) is

the primary source of energy– Examples: fruits, milk

and some vegetables; cookies, candies and soft drinks.

39g 65g 108g

Carbohydrates - ComplexComplex Carbs

• Known as Starch: many sugars linked together

• Must be broken down into sugar before usable– Examples: potatoes, rice, corn, pasta, bread &

cereal• Fiber can not be digested, but helps

system function.

Exit Pass

What are 3 of the 6 nutrients? How do we measure energy from

food?

Fats

• Fats contain twice the energy of Carbohydrates

• Fats protect & support organs and insulate you

• Cholesterol is a fatlike substance produced by the liver– You do not need

Cholesterol in your diet.

Types of Fat

• Unsaturated Fats are liquid at room temperature– Oils such as olive, fish

• Saturated Fats are solid at room temperature– Meats and dairy

products contain Saturated Fats.

FYI - Trans Fats

• Trans-isomer• An unsaturated fat

created in processed food production

• Increases risk of heart disease by raising levels of cholesterol.

Proteins

• Proteins mainly used for tissue growth & repair– Examples: meat, fish, dairy, nuts and beans

• Made of small units called Amino Acids

Vitamins(pg73)

• Vitamins help carry out chemical reactions in your body– Need only a small

amount of vitamins• Eating a variety of

foods will supply you with the vitamins you need.

Minerals & Water

• Minerals are nutrients not made by living things – found in soil– You get minerals by

eating plants• Water is essential

for circulating materials, making up 60% of our body mass.

Exit Pass

What is one thing fats do for our bodies? What is a Saturated Fat?