Transcript Fatsx

Chapter 7
Lipids
•
Fats are part of a complex group of nutrients known as lipids.
• Naturally occurring
• Cannot be dissolved in water
2 types:
Triglyceride –
• a basic fat molecule
• main component of fatty tissue
Sterols –
• lipids found in cell membranes
• cholesterol
Triglycerides
•
Purposes
• To help the body absorb vitamins A, D, E, and K
• To serve as an energy reserve
• To protect against temperature extremes
• To cushion and protect the heart and other vital organs
• To protect bones from injury
• To help you feel full longer
• And to help the body use carbohydrates and protein efficiently
Structure of fats (triglycerides)
•
Broken down by enzyme lipoprotein lipase (LDL)
Glycerol
• Fatty acids – basic building blocks of fats (3-tri)
•
Adipose cell – put fats back together and stored as
energy until the body requires it.
Essential fatty acids
•
Body makes some, but not all, fats for itself.
•
Fatty acid your body needs but can’t make is called an essential fatty acid.
• Omega-3 – linolenic acid
• May lower the risk of heart disease
• Salmon, sardines, mackerel, trout, herring
• Fax seeds, kiwifruit, walnuts, pumpkin seeds, sunflower seeds and
leafy vegetables
“Bad” Fats
•
Saturated fat
•
Lard
•
Trans fat
•
Shortening
•
Cholesterol
•
Mayonnaise
•
Gravy
•
Butter
•
margarine
Saturated fat
•
Primarily in foods from animals
•
Bacon
•
But also, coconut and palm oils
•
Butter
•
Chocolate
•
Coconut
•
Cream cheese
•
Fatty meat
•
Whole milk
Trans fats
•
Created by hydrogenating oils
•
•
Prolong shelf life
Look for words
•
•
Hydrogenated
Partially hydrogenated
•
Deep-fat fried foods
•
Cakes
•
Chips
•
Cookies
•
Crackers
•
Donuts
•
Imitation cheese
•
Margarine
•
Shortening
Cholesterol
•
A waxy, soft substance found among
the fats in the body and around cells
•
Needed to form cell membranes and
hormones
•
Too much is unhealthy – leads to
heart disease
•
Egg yolks
•
Whole milk products
•
Fatty meats
Cholesterol
•
LDL – low density lipoprotein
• Takes cholesterol from the liver
to wherever it is needed in the
body. “Bad”
• Excess LDL can build up in the
artery walls and increase the risk
of heart disease and stoke.
• Blood test – you would want
LDL to be low
•
HDL – high density lipoprotein
• Picks up excess cholesterol and
takes it back to the liver for
excretion.
• Good - “H” healthy or happy
• Blood test – you would want
HDL to be high.
“Good fats”
•
Monounsaturated fat
•
Polyunsaturated fat
•
Liquid at room temperature –
most oils
•
Lower blood cholesterol levels
•
Omega 3 – reduce inflammation
that helps to decrease cholesterol
buildup in artery walls as well as
pain from arthritis
•
Monounsaturated
• Avocado, canola, olive, peanut
and sesame oils, nuts olives and
peanut butter
•
Polyunsaturated
• Corn, cottonseed, safflower and
soybean oils, nuts seeds, and
fatty fish like herring, salmon
and tuna
Fat also…
•
Enhances flavor and texture of food
•
Adds moisture and tenderness to some foods
•
Adds crispiness to others
•
KEY: eat small, healthy amounts
Controlling fat
•
Cut fat you may be able to add more food without increasing calories
•
Substitute carbohydrates and proteins
•
Beware of hidden calories in low-fat and fat-free foods
•
Eat fruits, vegetables and whole-grain
•
Choose fat-free or low-fat milk, yogurt and cheese
•
Remove skin for chicken and turkey before eating
Controlling fat - continued
•
Choose lean cuts of meat – trim off and drain fat
•
Watch portion sizes
•
Limit fried foods
•
Limit the amount of cheese in your diet
•
Eat high-fat desserts only occasionally
What is fat?
•
True/False
Olive oil is a better fat for you than pancakes.
True
•
The amount of fat we eat impacts our weight & health more than the
type(s) of fat we eat.
False
•
Fat is made up of molecules called triglycerides.
True
•
Triglycerides are all alike
False
•
Fatty acid chains determine if fats are solid or liquid, if they go rancid quickly or how good
or bad it is for you.
True
•
Saturated fats are worse for you than trans-fats
False
•
The only way you know if trans-fats are in your foods is if you see the words “partially
hydrogenated” in the ingredient list.
True
•
Most unsaturated fats are good for you while saturated fats are bad if eaten in excess.
True
•
The FDA allows manufacturers to say a food has 0 grams of trans-fats even if it has .5 grams
True