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LIPIDS

lipids, triglyceride, unsaturated, saturated, phospholipids, cholesterol, wax, steroid

canola oil, butter, salad dressing, mayonnaise, avocado

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Lipids

Lipids are hydrophobic –”water fearing”

Includes fats, waxes, steroids, & oils

Do NOT mix with water

FAT MOLECULE

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Function of Lipids

Fats store energy, help to insulate the body, and cushion and protect organs

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Fats

Dietary fat consists of the molecule triglyceride composed of glycerol and three fatty acid chains

Glycerol

Fatty Acid Chain

Dehydration/Condensation links the fatty acids to Glycerol

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Triglyceride

Monomer of lipids

Composed of Glycerol & 3 fatty acid chainsGlycerol forms the “backbone” of the fat Organic

Alcohol

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Triglyceride

Glycerol Fatty Acid Chains

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H2C OH

HC OH

H2C OH

O

HO–C

O

HO–C

O

HO–C

Glycerol Fatty Acids

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H2C OH

HC OH

H2C OH

O

HO–C

O

HO–C

O

HO–C

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H2C OH

HC OH

H2C OH

O

HO–C

O

HO–C

O

HO–C

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H2C OH

HC OH

H2C OH

O

HO–C

O

HO–C

O

HO–C

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H2C

HC OH

H2C OH

O

O–C

O

HO–C

O

HO–C

H2O

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H2C

HC OH

H2C OH

O

O–C

O

HO–C

O

HO–C

H2O

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H2C

HC OH

H2C OH

O

O–C

O

HO–C

O

HO–C

H2O

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H2C

HC

H2C OH

O

O–C

O

O–C

O

HO–C

H2O

H2O

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H2C

HC

H2C OH

O

O–C

O

O–C

O

HO–C

H2O H2O

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H2C

HC

H2C OH

O

O–C

O

O–C

O

HO–C

H2O H2O

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H2C

HC

H2C OH

O

O–C

O

O–C

O

HO–C

H2O H2O

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H2C

HC

H2C

O

O–C

O

O–C

O

O–C

H2O H2O

H2O

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H2C

HC

H2C

O

O–C

O

O–C

O

O–C

H2O H2O H2O

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Triglyceride

H2C

HC

H2C

O

O–C

O

O–C

O

O–C

H2O H2O H2O

Water from Condensation/dehydration synthesis

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Types of Fatty Acids

Unsaturated fatty acids (better fats ie: oils)

Contain a double bond between carbons (liquids)

Saturated fatty acids (bad fats ie: shortening)

All single bonds between carbons (solids)

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Types of Fatty Acids

Single Bonds in Carbon chain

Double bond in carbon chain

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Fats in Organisms

Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)

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Fats in Organisms

Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils)

Polyunsaturated – many double bonds

*Best Choice*

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Types of Fatty Acids

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Trans Fat (the “Ugly” fat)

•Usually made from cis-unsaturated fats in an industrial process called “hydrogenation”

•“Hydrogenation” – conversion of unsaturated to saturated (solids)

•Have longer shelf life

•They increase LDL cholesterol levels and decrease HDL cholesterol levels

•Harmful as saturated fats – or WORSE!

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Cholesterol•NOT a “bad guy!” Our bodies make about 2 g of

cholesterol per day, and that makes up about 85% of blood cholesterol.

•Only about 15% comes from dietary sources.

•Found naturally in cell membranes and used to synthesize certain hormones – sex hormones

Two types of Cholesterol

LDL’s - Low Density Lipoproteins (bad)

HDL’s – High Density Lipoproteins (good)*reducing processed breads, pasta, and other highly

saturated foods can help decrease LDL accumulation*

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30% of the total energy intake should be in the form of fats.

– carbohydrates and proteins (4kcal/g) of energy

–9kcal/g for every gram of fat energy

__g of Carbs X 4kcal/g = __kcal __g of fat X 9kcal/g = __kcal __g of proteins X 4kcal/g = __kcal

Fats

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SteroidsThe carbon skeleton of steroids is bent to form 4 fused ringsCholesterol is the “base steroid” from which your body produces other steroids

Estrogen & Testosterone are also steroids

Cholesterol

TestosteroneEstrogen

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Synthetic Anabolic SteroidsThey are variants of testosteroneSome athletes use them to build up their muscles quicklyThey can pose serious health risks