Lipids A reserved fuel source that can be quickly stored and used depending on demand, 1gm of Fat is 9 KCALS Carbon, oxygen, hydrogen form a fatty acid joined on a glycerol backbone The number of CARBONS determines the structure and texture of the fatty acid The number of fatty acids joined to a glycerol chain determines monoglyceride, diglyceride, triglyceride

Fatty Acid Chains Short <6, Medium 8-12, Long 12-24; total carbons determine function Bonds determine saturation, single bonds are saturated, double bonds unsaturated The number of double bonds make a FA monounsaturated (MUFA) or polyunsaturated (PUFA)

Saturated & H+ Saturated fats are more solid, mostly found in animals and dairy, typically longer shelf life Unsaturated fats are more liquid and unstable with oils having a smoke point, mostly vegetables Hydrogenation is the adding of H+ to fatty acids for improved shelf life, by breaking double bonds Trans fatty acids are the product of hydrogenation which creates rigid FAs

Lipid Functions Carrier for fat soluble Vitamins A, D, E, and flavor, satiety, consistency, texture Essential FAs, linolenic, linoleic, and arachidonic, typically inflammatory response Linoleic are Omega-6 with double bonds starting at the 6th carbon, found in peanut and are pro-inflammatory Linolenic are Omega-3 with double bonds staring at the 3rd carbon, found in fish and are anti-inflammatory

Lipid Functions Cell membrane structure and barrier for permeability against cytotoxic agents Fuel supply and reserve once glucose and glycogen stores are depleted during catabolic state Formation of cholesterol for nutrient and hormone transport to muscle tissue and organs Lubricant for joints and glands especially with fluid deficit or cellular damage Protection, buffer for organs and bones from impact or trauma, insulation from cold weather, skin tissue

Fat Intake <30% of total KCALS, <7gm saturated, 4:1 MUFAs to PUFAs, no trans fats Replacing saturated fat with MUFAs improves heart health and adding PUFAs reduces overall disease risk Location of fat matters with visceral fat of internal organs adding risk compared to subcutaneous fat Lean fat 0-3gm, medium fat 4-7gm, high fat >8gm, with all types of fat still having 9kcals per gm Whole milk 8gm, 2% 5gm, fat free <1gm and LEAN meat at <10gm, EXTRA LEAN at <5gm