Fats, Carbohydrates, and Proteins

1. Name the 6 classes of nutrients.2. Identify the functions and food sources of cho’s,

protein, and fats.3. Describe the need for enough fiber in diets.

6 classes of Nutrients

Nutrition: the study or science of food and the ways in which the body uses it.

The 6 nutrients found in the food we eat are: fats are energy energy giving nutrients and are also

store energy in our bodies…, proteins are made of amino acids needed for growth and repair in our bodies… , carbohydrates are foods the give us energy and include sugars, starches…, and fiber, minerals, vitamins, and water.

Food and Fuel

Metabolism: the sum of chemical responses needed to keep us alive and active.

Calories: the heat energy in foods.Fats have 9/gram…protein 4/grams…

carbohydrates 4/gram

Carbohydrates

• Found in foods like fruit, milk, cookies, and potatoes.• 2 types: simple and complex• The sugar that circulates in your blood and provides energy

for our cells is a single unit sugar called glucose.• Other sugars are made of linked together sugars called

double sugars.• Table sugar is a double sugar made of glucose and fructose

called sucrose.• Candy, soda, and cakes are sweetened with refined sugars.

Refined sugars provided energy, but little nutrients.

Carbohydrates• Starches: are complex carbohydrates…many sugars linked

together. Most starches in our diet come from plants like potatoes, peas, beans, rice, corn, and wheat.

• It is recommended that 45% to 65% of our calories come from carbohydrates.

• Glycogen: stored glucose in the body fat…the bodies quick energy reserve…

• Fiber: complex carbs that provide little energy and cannot be digested by the body. Helps prevent colon cancer, heart disease, and constipation.

• Soluble fiber: mixes with water and creates volume, makes us full• Insoluble fiber: does not with water and makes us regular.

Fats• You need fat in your diet for your body to function properly. Fats also add to the

texture, flavor, and aroma of our food. But eating too much fat and eating the wrong kinds of fat can increase your risk of weight gain, heart disease, and cancer.

• Lipids: which are fatty or oily substances that do not dissolve in water. Fats are large molecules that are made up of two kinds of smaller molecules—fatty acids and glycerol.

• Three fatty acids are linked to one glycerol, which is why fats are also called triglycerides.

• Fatty Acids are generally considered good or bad for you.• Saturated Fat: Most saturated fats in our diets are solid at room temperature and

come from animal foods such as meat and milk. A few vegetable oils such as coconut and palm oil also contain saturated fat. If you eat a lot of meat, whole milk, butter, and ice cream, your diet will be high in saturated fat. This type of diet can lead to obesity, increase your blood cholesterol levels, and increase the risk of heart disease.

Fats• Unsaturated Fat: They are more common in plants and tend to be liquid at

room temperature. Unsaturated fats that contain fatty acids that have only one set of double bonded carbons are called monounsaturated fats. Monounsaturated fats are found in olive oil, canola oil, and peanut oil. Diets in fats mostly monounsaturated are believed to lower the risk of heart disease. Fats that contain fatty acids with more than one double bond are called polyunsaturated fats. Corn oil, sunflower oil, and soybean oil are good sources of polyunsaturated fat.

• Polyunsaturated fat: omega-3 is found in fish and seafood and may provide extra protection against heart disease.

• Trans fats: unsaturated fatty acids that are formed when vegetable oils are made into hard margarines. They may increase the risk of heart disease. Total fat intake for teens should be 25 to 35 percent of total Calorie intake with limited amounts of saturated fat, cholesterol, and trans fat.

Cholesterol

• It is found in all human and animal tissues. Cholesterol is needed to make vitamin D, cell membranes, the coverings on nerve fibers, certain hormones, and bile (a substance that aids in fat digestion). Your body makes cholesterol, but you also get cholesterol from your diet.

• One kind of cholesterol-containing molecule called lowdensity lipoprotein (LDL) brings cholesterol to the body cells. When levels of LDL cholesterol in the blood get too high, deposits called plaque (PLAK) form on the walls of blood vessels. Plaque can block blood flow to the heart muscle. Lack of blood flow starves the heart muscle of oxygen, causing a heart attack. Therefore, LDL cholesterol is known as “bad cholesterol.”

Cholesterol

• Another molecule, called high-density lipoprotein (HDL), carries cholesterol back to the liver, where it is removed from the blood. High levels of HDL cholesterol called “good cholesterol” are linked to a reduced risk of developing heart disease.

• Cholesterol is found only in animal tissue, so dietary cholesterol is found only in foods such as meat, fish, poultry, eggs, and dairy products. Cholesterol is not found in plants, so foods that come from plants are cholesterol free.

• When blood cholesterol levels rise, the risk of heart and blood vessel disease also increases.

Proteins

• Proteins in the body help build new cells and repair existing ones.Protein is also needed to form hormones, enzymes, antibodies, and other important molecules. If you eat more protein than is needed for these essential functions, it can be stored as fat. Proteins are made up of chains of molecules called animo acids.

• Nine amino acids are essential, which means the body does not make them.

Protein• Animal proteins such as meat, eggs, and dairy products contain all the

essential amino acids. These proteins are therefore called complete proteins.

• Most plant proteins, found in foods such as legumes, grains, and vegetables, don’t have all the essential amino acids or have smaller amounts of some essential amino acids than are needed by your body. These proteins are called incomplete proteins. A healthy diet must include all the essential amino acids.

• People who don’t eat meat can eat a variety of plant proteins to get enough amino acid to meet their needs. The combination of grains and legumes (as in a peanut butter sandwich) provides two different plant proteins that together supply all of the amino acids to meet the body’s needs. It is recommended that 10 to 35 percent of your total calories should be from protein.