HOSA Carbohydrates, Fats, and Proteins

How much of our calories do carbs provide?

About 50% in the US, up to 80 and even 100% in other parts of the world

How many calories per gram of carb?

4

How does the body store carbs

In the form of glycogen in liver and muscles

Protein sparing

Carbs spare proteins for their primary function of building and repairing body tissue

Carb sources

Cereal grains, wheat corn, rice, veggies like potatoes, beets, peas, lima beans. Green leafy vegetables provide fiber. Also fruit

Monosaccharides

simplest form of carbs, require no digestion

Glucose

(dextrose)- what everything else is converted to for cellular respiration, comes from corn syrup

Fructose

(levulose)- fruit sugar, in many fruits and honey, sweetest monosaccharide

Galactose

product of digestion of milk, not found naturally

Disaccharides

pairs of monosaccharides

Sucrose

glucose + fructose, in powdered, brown sugar and molasses, sweet. Comes from sugar cane, sugar beets, and the sap from maple trees (table sugar)

Maltose

Intermediate product of hydrolysis of starch, and created during alcohol fermentation. Not sweet. Two glucose molecules

Lactose

Found in milk and not in plants, helps body absorb calcium and phopshorous, less sweet. Glucose + galactose

Lactose intolerance

Cause be insufficient lactase

Importance of polysaccharides

Starch, glycogen, and fiber

Starch

Found in grains and vegetables, and is the storage form of glucose in plants. Found mostly in endosperm of grain, the center part

Whole/intact grains

Contain the outer bran coating, endosperm, and germ, and it is recommended that half our grains are whole

Refined grains

Only the endosperm, which is just starch, Less nutritous

Glycogen

About 1/2's day supply of energy is stored as glycogen in the liver and muscles. Hormone glucagon helps the liver convert glycogen into glucose for energy

Fiber

Cannot be broken down by digestive enzymes, some are soluble or not, and they absorb water in the large intestine, helping to create a soft, bulky stool, and satiation

Cellulose

Found in skins of fruits, great source of dietary fiber. No energy value and we cannot digest it. Forms important bulk to help pass food through along, stimulate normal muscle action in the intestine, and forms soft feces

Hemicellulose

dietary fiber found in whole grains

Lignins

Dietary fiber found in the woody parts of vegetables, noncarbohydrate, and also combines with bile acids and cholesterol in the human intestine to prevent their absorption even though it is insoluble

Pectin and mucilage purpose

Form a gel that helps provide bulk for the intestines. They also bind cholesterol, thus reducing the amount the blood can absorb

Recommended daily fiber intake

20-35g/day

Recommended fruit intake

2 cups a day

Recommended veggie intake

2.5 cups a day

Why are carbs so good for energy?

Wide availability, low cost, and storage capabilities

Enriched grains

Refined grain products in which some of the vitamins and minerals that were lost were added back

Fortified grains

Have nutrients like vitamins and minerals that have been added and would not have been found naturally

Soluble fibers

ex. mucilages, pectins, which bind bile acids and ultimately lower blood cholesterol levels

Insoluble fibers

ex. hemi and cellulose, lignin, help prevent constipation

Problems of too much fiber

Flatulence, bloating, and constipation

Carbs and the brain

Brain has no stored glucose; thus it requires a constant supply

Are fats water soluble?

No

How many calories per gram of fat?

9

Functions of fats

Cell membrane. Act as carriers for fat soluble vitamins ADEK. Provides energy when one cannot eat. Adipose tissue serves as insulation from the cold, and protects organs. Adds satiety to food

Meat sources of fat

red meats, like higher fat poultry cuts with skin like thigh and wing, milk, cream, butter, cheese, and egg yolks, and fatty fish like tuna or salmon

Plant sources of fat

avocados, cooking oil made from olives, sunflower, or sesame seeds, margarine, salad dressing, or mayonnaise

Do fats raise serum cholesterol?

Saturated fats from animal food does, which may contribute to heart disease. Plant fats do not raise cholesterol and are therefore more heart healthy

Visible vs invisible fats

Visible fats are purchased and used as fats, like butter or margarine. Invisible fats are in other foods like meat, mil, cheese, avocados, and nuts

Triglycerides

3 fatty acids and a glycerol, which is derived from a water soluble carbohydrate. 95% of body lipids

Two classifications of fatty acids- EFA

Essential fatty acids cannot be synthesized. long chain polyunsaturated fatty acids are derived from linoleic acid and linolenic acid. Consist of omega 3 and omega 6. Omega 9 is nonessential since the body can manufacture it

Other classification of fatty acids

saturation

Saturated fats

Contain max H. Mostly in animal foods, but chocolate, coconut, palm and palm kernel oil are exceptions. Solid at room temperature. No more than 10%, or even 7% of daily calories should be from saturated fats

Monounsaturated fats

have only one double bond. Contained in olive oil, peanut oil, avocados, cashew nuts. Lowers LDL cholesterol only when replacing saturated fats, and increases HDL. Recommended that 20% of total daily calories come from these

Polyunsaturated fats

two or more double bonds, and the location determines how the body metabolizes it. Foods include cooking oils from sunflower, safflower, or sesames and fish. Usually soft or oily. Should not exceed 10% of daily calories

Omega 3 fatty acids

denoted by placement of double bonds (3rd carbon). Alpha- linolenic acid with 18 carbons and 3 double bonds. Can lower risk of heart disease. Found in fish oils, so fatty fish is recommended

Omega 6 fatty acids

linoleic acid, with 18 carbons and two double bonds, has cholesterol lowering effect. Supplements are not recommended as a replacement

Trans-fatty acids

hydrogen atoms are added to unsaturated fats to produce a semisolid product. "partially hydrogenated vegetable oil" is an ingredient to look out for. Raise LDL and lowers HDL. Increases risk of developing heart disease or stroke, and type II diabetes

Hydrogenation

Process of making polyunsaturated fats into saturated fats by adding hydrogen, making it solid at room temp

What is cholesterol?

Fatlike substance that is a constituent of body cells, synthesized in liver and is found in animal products. Sterol with a structure of a bunch of rings adjacent. 800-1000 mg made a day in liver. No dietary requirement

Cholesterol functions

Synthesis of bile, sex hormones, cortisone, and vitamin D; present in every cell

Hypercholesterolemia

Unusually high levels of cholesterol and blood; also known as high serum cholesterol. Common in clients with atherosclerosis.

Athlerosclerosis

Plaque (fatty deposits) build up in arteries, leading to heart attack or stroke, if it is near the heart or brain

How to prevent high cholesterol?

Ingest little throughout life. Do not exceed 200mg/dL. Weight loss and exercise help. Soluble dietary fiber helps since cholesterol binds to it and exits as feces, and does not get absorbed in the small intestine

Lecitihin

fatty substance found in plant and animal foods; a natural emulsifer that helps transport fats in the bloodstream; used commerically to make food products smooth. Made up of glycolipids, triglycerides, and phospholipids

Too little fats leads to . . .

Eczema or dermatitis because of importance to membranes, slower growth, and weight loss

Too much fats leads to . .

Obesity and heart disease, as well as cancers of the colon, breast, uterus, and prostate

Two ends of a fatty acid

Methyl Ch3 group is the omega end and there is an acid carboxyl group COOH

What are lipoproteins?

Fat is insoluble and cannot freely travel in blood; thus hydrophilic proteins carry them around. They are combinations of triglycerides, protein, phospholipids, cholesterol, and other fat soluble substances

High density lipoproteins

Higher protein content. Carry free cholesterol from body tissues back to the liver for metabolism

Low density lipoproteins

Less protein content.Carry fat and cholesterol to the cells

Phospholipids

A molecule that is a constituent of the inner bilayer of biological membranes, having a polar, hydrophilic head and a nonpolar, hydrophobic tail.

Health benefits of polyunsaturated fats

No health benefits of replacing saturated fats with omega-6, but omega 3 fatty acids help lipid profiles and risk for heart disease

Health benefits of monounsaturated fats

Increases HDL, improves atherogenic index (ratio of total cholesterol to HDL cholesterol) and reduces vascular inflammation

Functions of protein

Build and repair body tissues, using protein from diet and recycled amino acids from the blood. Proteins make up hormones and enzymes, maintain fluid and electrolyte balances and prevent edema (abnormal retention of body fluids), and make up antibodies in the immune system. Provide energy at 4 calories per gram, although not optimal

Animal sources of protein and problems

Complete. Meats, fish, poultry, eggs, milk, cheese. Come with a lot of saturated fat an cholesterol

Plant sources of protein

Incomplete. nuts, sunflower seeds, sesame seeds, and legumes like soybeans, navy beans, pinto beans, split peas, chickpeas, and peanuts

Tofu

Made from soy milk, absorbs flavors of other ingredients easily, and rich in high-quality proteins and B vitamins, and low in sodium

Environmental issues of meat consumption

Large portion of crops are used to feed livestock, and they emit a lot of greenhouse gases, use a lot of water and create a lot of waste

Complete proteins

Contain the 10-13 essential amino acids that the human body cannot produce

Incomplete proteins

lack one or more essential amino acids, but eating a variety of these can provide all the essentials, and they are then called complementary proteins

Elements in protein

Every amino acid has nitrogen, and some have sulfur

Pepsin

Breaks down proteins into polypeptides

trypsin, chymotrypsin, carboxypeptidase

pancreatic enzyme; helps digest proteins

Metabolism and elimination of proteins

When amino acids are broken down. Deamination occurs, and ammonia is sent to the liver, converted to urea, and then filtered out by the kidneys. Other parts are stored

Situations where one needs more protein

Growing children, women who are pregnant or lactating, and athletes. Also after surgery, burns, or infections to replace lost tissue

Recommended daily protein intake

0.8 grams per kilogram of bodyweight, 10-35% of one's caloric intake

Problems of excess protein

Saturated fats and cholesterols in complete proteins contribute to heart disease, colon cancer and high calcium excretion, leading to osteoporosis. High protein may be to the neglect of fruits and veggies, and puts strain on the liver and kidneys (urea)

Protein and amino acid supplements

Not necessary; high quality protein foods provide bioavailable protein and cheaper. Usually have 20g of protein per scoop. Come from whey, sometimes casein, soy, bean, or pea protein

Nitrogen balance, and positive and negative

positive is more nitrogen intake than outgo- during pregnancy, development, and muscle growth. negative is the opposite, may be caused by fevers, injury, or surgery

Signs of protein deficiency

Loss of muscle mass in arms and legs. Albumin (protein in blood plasma) deficiency will cause edema, resulting in a swollen appearance. Loss of appetite, strength, and weight, and slow healing of wounds. Often leads to depression

Protein energy malnutrition

Results from lack of both protein and energy rich foods

Marasmus

Caused by above, and lack of vitamins and minerals. Extreme wasting, wrinkled skin, and irritability

Kwashiorkor

Extreme lack of protein causes fat to build up in liver, and lack of hormones results in edema, skin lesions, and changes in color of skin and hair

What do children with malnutrition often have when adults if they survive?

mental retardation

Products along the pathway of breaking down starch

Starch -> dextrin - > maltose -> glucose