Nutrition Exam 2

Describe function of fat in the body (7)

Provided unlimited energy (storage)

insulates the body (temperature)

protection of body organs

Transport of fat soluble vitamins/nutrients

Hormone regulation (compound synthesis)

Used in nervous system (neurotransmission)

Part of cell membrane

Functions of fat in food

Flavor and aroma

Texture

Satiety

Carries fat soluble vitamins

Source of essential fatty acids

Triglycerides

Most common lipid found in food and body

Consists of glycerol and 3 fatty acids

Fatty acids

Classified based on degree to which the carbon and is saturated with hydrogen

Saturated

Mono saturated

Polysaturated

Fatty acids is..

__ if it contains no carbon double bond

__ if it has only one carbon double bond

__ if it contains two or more carbon double bonds

Cis formation

When hydrogens on an unsaturated fatty acid lie on the same side of the carbon double bond

Trans form

When hydrogen on both carbons forming the double bond lie on the opposite sides of the bond

Lipid digestion

Mouth:

Stomach:

Pancreas:

Liver:

Small intestine:

Mouth: salivary lipase

Stomach: gastric lipase, stomach acids

Pancreas: secretes pancreatic lipase and other enzymes

Liver: secretes bile to emulsify fat in chyme

Small intestine: site of most fat digestion and absorption

AMDR recommendation of fat

20-35% of calories

Linoleic acid

Linolenic acid

Essential fatty acids:

Omega 6

Omega 3

Saturated fatty acids foods

Coconut oil, palm oil, bacon butter and lard

Monounsaturated fatty acid foods

Avocado, olive oil, canola oil, peanut butter

Polyunsaturated fatty acid foods

Salmon, nuts, plant sources, sunflower oil, soybean oil

Cholesterol foods

Only animal product (dairy, eggs, meat)

Omega 3 fatty acid foods

Cold water fish, canola oil, soybean oil, flaxseed oil

Omega 6 fatty acid foods

Corn, mayonnaise, sunflower oil

EPA and DHA and ALA

Types of omega 3 (linolenic) acid

EPA and DHA food sources

Cold water fish

ALA food sources

Flax, canola, soy, walnuts

Coconut oil is __ is saturated fatty acids than butter and beef fat

Higher

Omega 3 benefits in body (4)

Decrease blood clotting

Decrease circulation of triglycerides

Decrease swelling

Lower blood pressure

Affects of omega 6 on body (2)

Increase inflammation

Increase clotting

Atherosclerosis

Increase in fat in artery wall

Oxidized LDL from plaque

Narrowed arteries are at risk for clots

Components of an anti atherosclerosis lifestyle

Physically active

Good diet, low in saturated and trans fat

Stop smoking

Increase risk for cardiovascular disease

Age > 65

Diabetes

Smoking

High saturated fat diet

Cholesterol

Sterols

Phospholipids

In all cell membranes, 2 fatty acids and 1 phosphate

Chylomicrons

Lipoprotein produced in the small intestine

Takes long chain fatty acids and groups them together

Carries fat from the small intestine to the cells

VLDL

Lipoprotein that carries lipids made by the liver to cells

Broken down by lipase, broken down into glycerol and fatty acids

HDL

Roams the bloodstream, picking up cholesterol and donates back to the liver to be excreted

Nitrogen

Proteins contains __ which are the building blocks of protein

Which part of the chemical structure differentiates one amino acid from another?

The side chain

4 steps of protein synthesis

1. DNA code is copied from cell nucleus. Transferred by mRNA strand into cytoplasm

2. mRNA strand carries DNA to ribosomes, where protein translation occurs

3. tRNA (transfer RNA) adds amino acids from amino pool, to mRNA instructions, for a polypeptide chain

4. Polypeptide chain twists and folds into a 3D structure of the intended protein

__ amino acids in body

__ essential amino acids

20

9

Protein digestion

Stomach:

Pancreas:

Liver:

Small intestine:

Large intestine:

Stomach: pepsin and acid work to digest protein

Pancreas: organ releases trypsin to digest protein

Liver: Hypatia portal vein delivers absorbed amino acids and then to bloodstream

Small intestine: final digestion of amino acids to single amino acids

Large intestine: very little protein is present

How are amino acids used in cells?

They are converted to non essential amino acids

The nitrogen from amino acid breakdown is converted to __

Urea

Metabolism

Uses protein as energy

Function of proteins in the body

Synthesis of enzymes and hormones

Forms structure of bones and muscle

Immunity

Blood clotting

Transportation

What does the body do with extra protein?

Nitrogen is dismantled — and excreted through urine in kidney

Remaining amino acids are used for energy (glucose)

Stored as fat

Positive protein balance

Pregnancy, growing child, illness, athlete

Negative protein balance

Inadequate protein and caloric intake

Fevers, burns, infections

Protein loss (kidney disease)

Loss of body tissue

Protein equilibrium

Healthy adult meeting nutrient needs

— caloric and protein needs

Edema

Blood protein levels fall and fluid shifts into extra cellular spaces

Swollen limb and stomach

High quality proteins

Meat, fish, dairy, eggs

Low quality proteins

Vegetables and grains

Medium quality proteins

Nuts and legumes and seeds

Complimentary proteins

2 incomplete proteins, to make 1 complete protein

Rice and beans

MyPlate recommendations for protein

__ dairy

__ protein

__ grains

__ fruits

__ vegetables

8-10 g/cup dairy

7 g/oz protein

2-3 g/oz grains

1 g/c fruit

2-3 g/c vegetables

AMDR for total protein intake

10 - 35% of total calories

RDA for protein

0.8 g per kg body weight

__ kg = 1 lb

2.2 kg = 1 lb

When protein is converted to glucose or fat, nitrogen is eliminated from the body via __

Kidneys

Forms of protein calorie malnutrition (2)

Kwashiorkor and marasmus

Kwashiorkor characteristics (3)

Children go from breast milk to high starch and low protein diet

Fatty liver

Deficiency in protein, not necessarily calories

Rapid development

Marasmus characteristics (3)

Deficiency in protein and calories in diet

Develops gradually

Skin and bone appearance

Consequences of protein calorie malnutrition

Malnutrition

Slow growth

Impaired immunity

Impaired nutrient absorption

Impaired brain and kidney function

What is a potential problem with consuming individual amino acid supplements?

Impaired absorption of other amino acids

Nutrigenomics

Examines how foods impact health through its interactions with genes

Nutrigenetics

Effects of genes on nutritional health

Ex. Responsiveness to dietary modifications

Epigenetics

The study of heritable changes in gene function that are independent of DNA sequence

Vegan diets have a lack of __ (6)

Protein

Vitamin B12

Zinc

Iron

Calcium

Omega 3 fats

Vitamin D

Basal Metabolic Rate

Energy expenditure, especially breathing (60-75%)

Factors that decrease BMR

Insufficient thyroid hormone production

Aging

Less body surface area

Very low calorie diet

Factors that increase BMR

Pregnancy

Stress, caffeine

More body surface area

Illness

High body fat %

Basal metabolism

Supports body functions — heart lungs brain

Adaptive thermogenesis

Body’s adjustment to energy expenditure related to changes in environment such as extreme cold

Thermic effect of food

Energy used to digest food, increase in metabolic rate after eating

Underweight:

Normal:

Overweight:

Obese:

Underweight: <18.5 kg

Normal: 18.5-24.9 kg

Overweight: 25 - 29.5 kg

Obese: >30 kg

Waist circumference (central obesity spot)

Measurement to be considered obese:

Female: >30 in

Male: >40

Risks for BMI weight

Low:

Moderate:

High:

Low: underweight

Moderate: normal weight

High: obese

Sleep apnea

Excess weight puts pressure on pharynx and lungs

Heart disease

Excess weight and enlarged adipose cells increase LDL

Cholesterol, triglycerides, blood clotting, and inflammation

Gallstone formation

High fat and cholesterol diet increases cholesterol in bile

Liver damage

High fat diet lead to excessive fat in liver erectile dysfunction in mend

Excess weight causes inflammation and reduced function of red blood cells

3 ways for successful weight loss

Modification of behaviors

Decreased calorie intake

Increased physical activity

Factors of healthy weight loss

Long term

Variety of food groups

Equal to about one pound a week

In amino acid breakdown, what part of the amino acid is used for energy?

Carbon skeleton

How can a vegan get more B12 vitamin?

Drink fortified soy milk, fortified ready to go cereal, or a B12 supplement

Visceral fat

Excess at in the abdomen

Higher likelihood of risk of disease

Basal metabolism examples

Hormone secretion

Beating of heart

Respiration

Bile

Emulsifies fat, produced in the liver, helps with fat digestion

Lipoprotein

Carries fat soluble compounds in the bloodstream

Mouth (fat)

Salivary lipase

Stomach (fat)

Gastric lipase

Stimulates liver to produce bile salts to emulsify fat

Small intestine (fat)

Pancreas is stimulated to release pancreatic lipase and fully break down triglycerides

Micelles are present

Fatty acids in fat digestion

Enter intestinal lining, then into blood

Long chain fatty acids in fat digestion

Packed into chlyomicrons

Chlyomicrons

Lipoproteins that transport lipids into tissues in body then lymphatic system then bloodstream

What do triglycerides break down into?

Glycerol

Monoglyceride

Fatty acids

What is responsible for lipid transportation? (4)

Lipoproteins IN LIVER

Chylomicrons, VLDL, LDL, HDL

VLDL

Transport cholesterol from liver to cells

Lipase breaks down into glycerol and fatty acids

LDL

Transport cholesterol for cell membranes

Risk of heart disease if levels are too high

Cholesterol

Produced in liver, stores energy

Helps with hormone production, propels bile, maintains stability of CELL MEMBRANE

Phospholipids

2 fatty acids and glycerol

Lecithin

Forms cell membrane

Lecithin

Emulsifier in fat

Stomach (protein)

Pepsin, denatures protein (unravels protein for easier digestion)

Starts to break peptide bonds

Small intestine (protein)

Partially digested protein triggers CCK

Single amino acid absorption in intestinal walls

CCK

Cholecystokinin

Triggers pancreas to release trypsin and split proteins