1 glycerol + 3 fatty acids

fatty acids can be saturated, monosaturated and polyunsaturated

no double bonds

solid at room temperature

usually of animal origin

Ex: butter and lard

exception is coconut oil and palm oil, they are saturated fats but from plants

one double bond

liquid at room temperature, but will become solid if refrigerated

food sources: olive oil

2 or more double bonds

liquid at room temperature or refrigerated temperature

usually of plant origin

food source: corn oil

Fatty Acids

Found in vegetable oils and meats

Deficiency uncommon, but more common if you have chronic disease

 constituent of cell membranes

 emulsifying agent (helps fat and water mix- also used in food industry)

starting material for cholesterol, bile acids, sex hormones, adernal hormones, vitamin D

Cholesterol can be converted to all of the above, and is a sterol that is found in foods of animals

cholesterol

it can either be reabsorbed and reused or it can be trapped by soluble fiber in the intestine and then excreted

chylomicrons

VLDL

LDL

HDL

"bad cholesterol"

LDL gives up cholesterol to cells

"good cholesterol"

transports cholesterol back to liver from the cells for disposal

Heart Disease

-Elevated blood cholesterol is a major risk factor in heart disease

-Dietary saturated fatty acids raise blood cholesterol more than dietary cholesterol does (raises LDL and lowers HDL)

diets high in fish oils lower blood cholesterol and reduces risk of heart disease

recommended that fish be consumed at least once a week

weight control

mono and polyunsaturated fats in diets

soluble fibers (oatbran)

antioxidants (vit C and E)

moderate alcohol consumption

exercise

being female!

hydrogen gas is mixed with a liquid fat (oil)

Hydrogenation causes fatty acids to be more saturated and thus more solid

Hydrofenated corn oil = margarine

Hydrogenation also causes formation of trans fat

Common in margarine, baked products, snack chips/crackers

trans fatty acids are unhealthy because they may increase heart disease

Reduce Total Fat Intake (20-35% or less of kcal but dont go less than 15%)

Reduce Saturated Fat Intake (<10% of kcals)

Reduce Cholesterol Intake (<300 mg/day)

Select lean meats and nonfat milks

Eat plenty of vegetables, fruits and grains

Use fats and oils sparingly

the irreversible change in a proteins shape which is brought about by heat, acid or other agents.

ex: hardening of an egg due to cooking

*shape of protein molecules is very important.

In the stomach -> hydrochloric acid uncoils the protein; enzymes attack the protein

In the small intestine -> pancreatic and intestinal proteases further degrade the protein

Positive Nitrogen Balance

(Protein metabolism)

retaining protein that you're eating

intake > output

ex: pregnancy, growth, muscle building

intake < output

ex: weight loss diet, illness

Equilibrium

intake=output

does not contain all 9 essential amino acids needed for protein synthesis

*typically plant proteins

does contain all 9 amino acids needed for protein synthesis

*typically animal products

2 or more proteins whose amino acids profiles complement each other to form a complete protein

*must eat within the same day

0.8 g/ kg BW

* need adequate energy (carb) in diet, to "spare protein" so prof is not used for energy

avoids meat, fish and poultry (may eat eggs and dairy)

*most common type in the US and Canada

low in cholesterol, saturated fat

high in fiber

Vegetable sources of protein tend to be incomplete

must complement plant protein sources to receive all necessary amino acids

complementary plant proteins must be eaten with in the same day

Vit. B12 (only in animal sources)

Calcium

Protein

Iron

Zinc

Vit. D

not enough reserves

can't fight wasting disease (cancer)

increased chronic disease with obesity

central obesity ("apple shaped") is especially dangerous because its associated with heart disease

Basal Metabolic Rate (BMR)

-For metabolism, breathing, temperature maintenance while at complete rest

intentional activity

ex: walking, running, moving

Anthropometry

Underwater Weighing

Bioelectrical Impedence

DEXA

BodPod

electrical current

fat has different electrical resistance than muscle

x-rays

fat responds differently to x-rays than muscle

estimates body volume by measuring air pressure

get body density (body mass/volume) and then can estimate body fat from body density

Hunger: prompts eating, physical need to eat

Satiation: signals to STOP eating

Satiety: lack of hunger

Appetite: psychological desire to eat

Obesity is influenced by total # of fat cells in body

Most fat cells are formed during childhood

Can limit number of fat potential if limit # of fat celss in childhood. (prevent childhood obesity)

Palabilty of foods

Food availabilty

Psychological Factors in obesity?

Age and Lifestyle Factors?

loneliness, addiction, depression and stress

physical inactivity

chronic irreversible disease characterized by degeneration of body organs

Multi factoral causes -> one being lifestyle choices (smoking, poor dietary habits, alcohol use, physical inactivity)

#1 cause of death in developed nations

both men and women are at risk... men experience more attacks

>61 million in US suffer from it

most common form of CVD

characterized by plaques along inner walls of arteries

causes: diets high in trans fats and saturated fats, high LDL

2nd leading cause of death in the US

disease in which cells multiply faster than normal and disrupt normal functioning of organs

Exposure to carcinogen, can be food substances; from environment etc.

excess protein, sodium, caffeine and soft drinks

poor nutrition

being underweight

frequent

not toxic

Thiamin

-deficiency?

-dietary source?

Deficiency: Beriberi

Dietary Source: pork, whole grains, enriched grains

Riboflavin

-dietary source

-deficiency symptoms

dietary source: milk/milk products, eggs and enriched grains

deficiency symptoms: cracks at corner of mouth, sensitivity to light

Niacin

-Dietary Source

-Deficiency Symptoms

Dietary: protein foods, enriched grains

Deficiency: Pellegra

* Can have toxicity symptoms (skin flushing, blurred vision)

required vitamin B12 to function

dietary sources: green vegetables, enriched grains, legumes

deficiency: neural tube defects (in infants) and impaired cell division

benefits pregnant women and the elderly

Maintains the sheath that surrounds and protects the nerves

only animal based foods

dietary source: meat, fish and bananas

deficiency: rashes, scaly skin, anemia

toxicity symptoms: nerve damage

sulfur containing vitamin

widespread in foods

deficiency: depression, muscle pain

widespread in foods

deficiency: intestinal problems, hypoglycemia and insomnia

anitoxidant, cancer prevention, helps iron absorption

citrus fruit, cabbage type veggies and dark green veggies

scurvy: bleeding gums, impaired wound healing

beta-carotene

Major Functions: vision, promote cell growth, support immune system, antioxidant

Dietary: liver, fortified milk and breakfast cereals, greens, sweet potatoes, spiniach

Deficiency: Night blindness, poor growth, dry skin

Toxicity seen in supplementation not from eating too many fruits and veggies

Synthesized in the body by sunlight

increased absorption of calcium and phosphrous

only animal based foods have significant amounts

deficiency: growth retardation and softning of the bones

important antioxidant

may decrease risk of heart disease

vegetable oils, nuts and seeds, some greens and eggs

deficiency and toxicity: not common

functions: blood clotting

dietary source: leafy green veggies, milk, GI bacteria