Lipids Objectives List the 3 forms of lipids

Lipids

Objectives • List the 3 forms of lipids and describe differences between each • Know what forms a triglyceride • Discuss how saturation and configuration of a fatty acid impact shape and form • Identify the essential fatty acids and their roles • Understand the process of lipid digestion, including cholesterol packaging • Discuss the role of fats in the body

What are Lipids? • Made of 3 atoms: • Distinguished by insoluble nature • Come from _________ • Stored as __________ • Fats are: • 3 forms of lipids:

Triglycerides + • Fatty Acid – a long chain of atoms bound to other Carbon atoms and Hydrogen • Glycerol: the “backbone” – An alcohol made of 3 carbon atoms

• Numbering: – From Carboxyl (COOH) end, the α-carbon – From methyl group (CH 3) end, the ω-carbon

Fatty Acid Chain Length • Determines ______, _______ & _______ in the body • Short-chain fatty acids – Fewer than 6 C’s • Medium-chain fatty acids – 6 -12 C’s long • Long-chain fatty acids – 14+ C’s long

Saturation levels • Saturated (SFA) – – at room temp • Mono-unsaturated (MUFA) – – at room temp • Polyunsaturated (PUFA) – – at room temp

Figure 5. 3

Unsaturated FA shape Figure 5. 4 • Cis – H on _______ side of double bond – In nature • Trans – H attached on _____ side – Straighter

Trans fats • Product of a process called ________ • Molecules are straightened, making oils _____ at room temp • Purpose? • Margarine vs. butter?

Review: How are fats classified? What determines their function? • 1) • 2) • 3)

Essential Fatty Acids • What makes them “essential”? • What are they known as & called?

• Omega 3’s - Alpha Linolenic Acid – Fish & plant sources • Omega 6’s - Linoleic Acid – Nuts & vegetable oils • EPA & DHA – Reduce the risk of heart disease

Phospholipids • Lipid + ________ • Water soluble • Produced by the body – Are they essential? • Transport fat, regulate transport in & out of cells, aid in producing bile

Sterols • What is the most common? – ____________ – Is it essential? • Plant Sterols – Block absorption

Lipid Digestion • Mouth • Stomach – Reduce to smaller droplets • Small Intestine – Triglycerides are broken down by ______ into ____________

Accessory Organs • Liver – __________ – Lecithins assist bile • Gallbladder – The hormone ____ signals ________ • Pancreas – Releases enzymes to breakdown fatty acids

Absorption • Occurs in __________ Long Chain Fatty Acids • Lipids & lipid products are packaged into in the small intestine – Components then free until packaged as a for transport Short & Medium chain fatty acids • Packaged only by for absorption

enzyme?

Triglyceride’s for energy • Must be broken apart by LPL for cell use • Create lipid containing compounds • Stored in 2 places – __________________ – Is there a preference?

Why do we need lipids? • For the body: • In food:

How much? • Healthy population AMDR: • Best for athletes: • Linoleic: 11 -17 g/day • ALA: 1. 1 -1. 6 g/day • Saturated:

What do we know impacts CVD? • Cardiovascular disease: dysfunction of the heart & blood vessels, that leads to heart attack & stroke

Prevention & Improvement • Decrease intake of: • Polyunsaturated intake: • Monounsaturated intake: • Cholesterol • Omega-3’s • Fiber, alcohol, exercise

Medications • Statins – Lipitor, Crestor, zocor, lovastatin, etc. – Decrease cholesterol production by liver • Niacin – Megadoses can improve all lipids

Fat & Cancer? • Controversial findings • High fat intake increases oxidation • Non-controversial on ______ cancer – Association with animal fat intake