HLTH 1107 | Lipids

Functions of fat in our bodies

80-90% of resting body's energy, cell membrane, energy stores, padding, insulator, fat soluble vitamins A, D, E, K

Essential

We need it; body cannot make it

Essential fatty acids

Omega-3 and omega-6

Essential fatty acid lacking in diets

Omega-3

Sources of essential fatty acids

Fish, flax seed, human breastmilk, canola oil, chia seeds

Health Benefits of consuming fish oil

Lower risk of heart attack

Recommendations for Omega 3 Fatty acids

2 or more fish meals a week

Fish oil supplements

Look for 'purified to remove mercury' and 'USP Certified'

Fish to avoid for mercury intake

Swordfish, king mackerel, shark

Functions of fat in food

Great calorie source, food more appealing, food has more crisp, feel full longer, fat transports fat soluble vitamins, appetite stimulant

Dietary Recommendations for fat

Total fat: 20-35% of total calories, Saturated fat: between 5-6% of total calories, trans fat: limit

Saturated fat

All carbons are saturated by hydrogens

Hydrogenation

Occurs when a polyunsaturated fatty acid (PUFA) is hydrogenated

Monounsaturated Fatty acid

One point of unsaturation (one carbon double bond)

Polyunsaturated fatty acids

Two or more points of unsaturation (PUFA) (two or more carbon double bonds)

Food Sources for Saturated Fat

Coconut oil, palm oil, lard, butter

Problems with a diet high in trans fat

Increase risk of heart attack by raising blood LDL cholesterol, lowering blood HDL, tissue inflammation

Type of fat for heart health

Unsaturated fat

Phospholipid

Glycerol + two fatty acids + phosphorus

Emulsifying ability of phospholipids

Phosphorus makes it soluble in water

Emulsifying property in eggs

Egg contains lecithin

Trans Fat

Solid at room temperature

Unsaturated fats

Liquid at room temperature

Example of a Sterol

Cholesterol

Cholesterol sources

Only in animal products

Role of cholesterol

Bile, vitamin D

Lipoproteins mentioned

LDL & HDL

Difference between LDL and HDL

HDL is healthy, packed with more protein, carries fewer & gets rid of cholesterol; LDL carries cholesterol to tissues and deposits it

Terminology to Define

Hydrogenation, Pancreatic Lipase, Monoglyceride, Triglyceride, Emulsifier, Lipoprotein, HDL, LDL, Trans fat, Ketosis, Linolenic Acid, Linoleic Acid, Bile, Phospholipid, Lecithin, Partially Hydrogenated