Lipids - Part 1 Flashcards
What are lipids?
Lipids are fixed oil, fats, waxes:
They are all esters of long chain fatty acids and alcohols, or closely related derivatives.
What are fixed oils and fatty acids?
Fatty acids are fixed oils, they are
* Non-volatile (they do not evaporate unlike essential oils)
* Low polarity molecules - they don’t dissolve in water tho will in other fixed oils
* Fixed oils are composed of fatty acids. They are hydrocarbon chains with a methyl group (CH3) at one end, and a carboxyl group (COOH) at the other end.
Example fixed oils are castor oil, oilive oil, sunflower oils. Most are in seeds and nuts. Very high energy food strorage compounds. Essential oils are NOT fixed oils.
Fatty acids can be classified as follows:
Saturated (no bonds) or unsaturated (there are existence of double bonds - one or more)
Omega classification: location of the first double bond, counting from methyl end.
Some examples of fatty acids: caprylic acid, palmitic acid, parmitoleic acid, linoleic acid.
What are triglycerides and phospholipids?
A triglyceride is three fatty acids, bonded to one glycerol (= can also be called triacylglycerol as well as triglyceride).
Found in most cell membrances. Cell membrane phospholipids have two fatty acids and a phosphate.
The type of fatty acid has an influence on fluidity and structure of cell membrane. Cold weather oils tend to be unsaturated = more fluid (eg a fish to allow swimming). Tropical oils – are usually saturated, resist oxidation in the heat. Stored in seeds, oily fruits.
Coconut oil is an example of tropical:
* Medium-chain triglycerides, which contain mainly lauric acid, a saturated fatty acid.
* Waxy consistency at room temperature
Saturated fatty acids (SFAs) do not have double bonds in hydrocarbon tail. Long, regular zigzag architecture which affects how they can stack and build.
What are monounsaturated fatty acids?
Monosaturated fatty acids are NOT saturated as they have** one double bond**.A bit thicker than a polysaturated oil. Found in olive, canola, peanut, corn, avocado, almond oil.
Contains Oleic acid, omega 9.
Oleic acid:
Suppressed expression of several oncogenes in vitro.
Reduced C-reactive protein (produced by the liver when inflammation happening in body), cardioprotective.
Reduced (bad) LDL cholesterol in hypercholesterolaemic men.
What is Palmitoleic acid?
- Omega-7 molecule
- Found mainly in sea buckthorn, macadamia nuts, and some in avocado, palm, coconut, olive oil and various other nuts.
- Diet rich in macadamia nuts: lowered LDL cholesterol, and lowered biomarkers of inflammation and thrombosis (risk for coronorary artery disease).
- Clinical trial oral, sea buckthorn oil; dry eye - intensity of redness and burning was reduced.
What are Polyunsaturated fatty acids (PUFAs)?
Have two or more double bonds:
* Omega-6 series derived from linoleic acid in sunflower oil, hempseed oil.
* Omega-3 series derived from
alpha-linolenic acid (ALA) in flaxseed oil, hempseed and small amounts in seeds, nuts.
These must be in daily diet. The body can’t make either of these. Crucial for brain and central nervous system - fluidity and flexibity of membranes.
Too much of Omega-6 will lead to a higher inflammatory response in the body however. Good to have a mix, a ratio of Omega 3-Omega 6 of 1:3 to 1:5 to manage the inflammatory response - Western diet is likely more like 1:20
What are the benefits of omega-3s?
Least inflammatory environment: combination of Ω-3s & Ω-6s in proper ratio. Omega 3:
* Inhibits pro-inflammatory prostaglandins.
* Reduces thrombosis.
* Lowers plasma cholesterol & triglycerides, inhibits vascular inflammation.
* Lack of 3/excess 6: elevated homocysteine (risk factor for CVD).
* Low level of 3s associated with depression,
and also ADHD in children.
* Beneficial for metabolic syndrome.
* Associated with increased hip bone mineral
density for brittle bones. In vivo; shown it enhances bone formation.
A wide range of benefit to many conditions.
What is GLA?
Evening primrose oil: source of gamma-linolenic acid (GLA), an Ω-6 fatty acid
* Long-term use may potentiate the
risk of arachidonic acid build-up in the treatment of rheumatoid arthritis, so important to take with Omega 3.
