Fat, Carbs And Protiens

35-2 Nutrition Bio 30 NWRC

Calories • Calories made of: carbohydrates, protein, and fat • Kilocalorie (kcal, 1000 Calories) A calorie is a unit of energy needed to raise 1mL of water by 1*C • How many calories do you need each day? Total calories= BMR + energy for activity

Calories Example: a 140-lb., lightly active woman BMR calories: 140 x 10= 1400 + Activity calories: 1400 x 30% = 420 Total calories needed to maintain current weight = 1400 + 420 = 1820 calories To lose weight/gain weight: +/- 500 calories a day (1 lb. = 3500 calories)

What is Normal??? • The most important part of being a normal weight isn't looking a certain way - it's feeling good and staying healthy. Having too much body fat can be harmful to the body in many ways.

Fat, Carbs and Proteins

Calories come from….

•Fat •Proteins •Carbohydrates

Carbs • Carbohydrates meet your body’s energy needs – Feed your brain and nervous system – Keep your digestive system fit – Within calorie limits, help keep your body lean – Together with fats and protein, digestible carbohydrates add bulk to foods – Indigestible carbohydrates yield little or no energy but provide other benefits

Carbohydrates • Glucose produced by photosynthesis provides energy for the work of all parts of the plant – Plants do not use all the energy stored in their sugars • Some remains available for use by the animal or human that consumes the plant – Carbohydrates are the first link in the food chain that supports all life on Earth

A Close Look at Carbohydrates • Fiber – Some plant fibers provide support to plant structures (cellulose) – Fibers also retain water to protect seeds from drying out – Most fibers are polysaccharides

A Close Look at Carbohydrates • Starch – Starch is a plant’s storage form of glucose • For example, corn stores clusters of starch molecules in granules and packs the granules into its seeds – This insoluble starch will nourish the seed until the new plant is capable of photosynthesis – Soluble glucose would be washed away by rain

• Starch is nutritive for people because they can digest starch to glucose and obtain the sun’s energy stored in its chemical bonds

A Close Look at Carbohydrates • Carbohydrate-rich foods come almost exclusively from plants – Milk is the only animalderived food that contains significant amounts of carbohydrate

Carbohydrates • Main source of calories in a healthy diet • Primary fuel source for brain and muscles; helps maintain functioning of nervous system • Approximately 55-75% of daily calories should come from carbohydrates • There fore the 140 lb woman from previous example can eat up to 1365 calories (of her 1820) of carbohydrates a day.

From Carbohydrates to Glucose • Starch found in refined grains is rapidly broken down to glucose which is then absorbed • Starch, such as that of cooked beans, digests more slowly and releases glucose later in the digestive process

From Carbohydrates to Glucose • Digestion and Absorption of Carbohydrate – To obtain glucose from food the digestive system must first break down carbohydrates in the food into monosaccharides that can be absorbed

Storing Glucose as Glycogen • During digestion, chemicals in your digestive tract break down carbohydrates into glucose, which is absorbed into your bloodstream which delivers it as an energy supply to all your body cells. • Your pancreas responds to the glucose by releasing insulin. • Insulin is a hormone responsible for allowing glucose into your body's cells.

Glycogen • Glycogen is the body's main source of stored energy. Made from glucose (from excess carbs), glycogen is stored primarily in liver (and muscle cells).

A Close Look at Carbohydrates • Excess glucose is stored in the liver in the form of Glycogen – Glycogen is the storage form of glucose in animals – There is little glycogen in meats because it breaks down rapidly when the animal is slaughtered

Insulin and Glucagon • Insulin is secreted by the pancreas when blood sugar rises –Insulin signals body cells to convert glucose to glycogen which is stored in the liver (mainly) • Glucagon is secreted by the pancreas when blood sugar is low – this tells the liver to convert glycogen to glucose and release to body cells. • We will look at this more in-depth in the next section…

Calories come from….

•Fat •Proteins •Carbohydrates

Usefulness of Fats in the Body • Essential nutrients – The fat-soluble vitamins (A, D, E, and K) are soluble in fat • Found mainly in foods that contain fat – Absorbed more efficiently from these foods – Fat also aids in the absorption of some phytochemicals

– Essential fatty acids • Serve as raw materials from which the body makes certain required molecules

Saturated versus Unsaturated Fatty Acids • Saturation refers to whether or not a fatty acid chain is holding all of the hydrogen atoms it can hold – Point of saturation • Site in a molecule where the bonding is such that additional hydrogen atoms can easily be attached

•

Usefulness of Fats in the Body Fat is the body’s major storage form of energy – Fats pack tightly together without water • Relative to carbohydrate, much more fat can be stored in a small space

– Gram for gram, fats provide more than 2x the energy of carbohydrate • Making fat an efficient storage form of energy

•

Usefulness of Fats in the Body Most body cells can store only limited fat – Some cells are specialized for fat storage • These fat cells seem to expand indefinitely – The more fat they store, the larger they grow

• Adipose (fat) tissue secretes hormones and produces enzymes that influence food intake and affect the body’s use of nutrients

Usefulness of Fats in the Body • Fat – Body’s chief storage form for the energy from food eaten in excess of need • Valuable survival mechanism for people who live a feast-or-famine existence

– Provide most of the energy needed to perform much of the body’s work • Especially muscular work

Usefulness of Fats in the Body • Other functions of fat – Shock absorbers • Pads of fat surround vital internal organs

– Thermoregulation • Fat pads under the skin insulate the body from extremes of temperature

– Cell membranes • Lipids are a component of cell membranes This is 5 lbs of body fat

Saturated Fats are Saturated with Hydrogen

What is “Hydrogenated Vegetable Oil,”... • Hydrogenation – Prevents spoilage of unsaturated fats – Makes unsaturated fats harder and more stable when heated to high temperatures

Calories come from….

•Fat •Proteins •Carbohydrates

PROTEIN

Approximately 10-15% of calories should come from protein

PROTEIN • 20 different amino acids • 12 made by our body = 8 essential amino acids (must be obtained through diet)

PROTEIN RDA for average sedentary adult= BW (body weight) x 0.36 So if you weight 140LBs X0.36 =your RDA is 50.4 grams Active adult: BW x 0.4-0.6 Growing athlete: BW x 0.6- 0.9 Adult building muscle mass: BW x 0.6-0.9

PROTEIN Example: • A sedentary adult who weighs 15o lbs. needs 54 g/ day • What does this look like? 1 bowl Raisin Bran and 1 cup milk (12 g) + 1 small Burger on Whole Wheat Bun (20g) + 1 cup Pasta with 1 cup assorted vegetables and beans (22 g) = 54 grams of protein!

PROTEIN 1 cup kidney beans………………………………..15 g 1 cup lentils…………………………………………..18 g ½ cup tofu……………………………………………14 g 1 cup milk ………………………………..8 g 1 veggie burger (Boca burger)….................13 g 1 Hamburger Patty …………………………………22g 2 T peanut butter……………………………………9 g ¼ cup walnuts…………………………….............4 g 1 slice whole wheat bread………………… ……..3 g 1 cup oatmeal…………………………………………6 g 1 cup cooked brown rice…………………………..9 g

Vitamins and Minerals • A vitamin is an organic compound required as a nutrient in small amounts • Vitamins are classified as either watersoluble, meaning that they dissolve easily in water, or fat-soluble vitamins, which are absorbed through the intestinal tract with the help of lipids (fats). In general, watersoluble vitamins are readily excreted from the body.

Vitamins and Minerals • Minerals are the chemical elements required by living organisms for metabolic functions. Iron is one example (from text) calcium, sodium, & potassium are others

Assessment • 1.Balancing calories consumed and calories expended helps to maintain a healthy body weight

Assessment • 2. • A. Carbs= quick energy • B. proteins and fats =energy and molecular building blocks

Assessment •

•

3. People following a vegetarian diet must eat protein foods that have complementary proteins so that the essential amino acids missing from one protein food can be supplied by another. What are some examples of complementary proteins? Beans and tortillas

•

Peanut butter sandwich

•

Macaroni and cheese

•

Tofu with rice

•

Hummus with pita bread

•

Hummus with falafel

•

Chickpeas and rice

•

Assessment • 4. Vitamins help enzymes function well and minerals are used by the body as building materials and are involved in basic metabolic functions