Omega Three Fatty Acids Flashcards
What are fatty acids?
n−3 fatty acids (popularly referred to as ω−3 fatty acids or omega-‐3 fatty acids) are a family of unsaturated fatty acids that have in common a final carbon-carbon double bond in the n−3 position; that is, the third bond from the methyl end of the fatty acid.
How do chemists name fatty acids?
Counting carbons from the carbonyl carbon, ALA has a chain of 18 carbons with 3 double bonds, in positions 9, 12 and 15.
How do physiologists count carbons on omega-three fatty acids?
physiologists count from the n (ω) carbon (red numbering).
Note that from the ω end (diagram right), the first double bond appears as the third carbon-‐carbon bond (line segment), hence the name “ω−3”.
This is explained by the fact that the ω end is almost never changed during physiologic transformations in the human body, as it is more stable energetically, and other carbohydrates compounds can be synthesized from the other carbonyl end, for example in glycerides, or from double bonds in the middle of the chain.
What are the three main fatty acids?
The three main omega-3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA)
Give a bit of history for the halth of omega three fatty acids.
Late 1970s Danish scientists demonstrated that Greenland Inuits had significantly lower levels of coronary heart disease
Also noted in Japanese islanders with high fish diets (Kagawa et al 1982)
These initial studies led to thousands of studies into the effects of omega 3 fatty acids on health
What is Lorenzo’s oil?
Lorenzo’s Oil is a combination of a 4:1 mix of oleic acid and erucic acid, extracted from rapeseed oil and olive oil designed to normalize the accumulation of the very long chain fatty acids in the brain thereby slowing the progression of adrenoleukodystrophy (ALD). It is specific to ALD and is NOT designed to be used to treat other leukodystrophies nor multiple sclerosis.
How does lorenzos oil work?
How it Works
The oil, if started early in boys with adrenoleukodystrophy (ALD) showing no symptoms, is now known to have some benefit in preventing the childhood cerebral form of adrenoleukodystrophy. Researchers are still trying to understand the complex relationships among fats in the body, and how Lorenzo’s oil could be further modified to be more effective. The oil is designed to normalize the accumulation of the very long-chain fatty acids in the brain that thereby halting the progression of ALD.
Why does omega-three need to come from diet?
The polyunsaturated fatty acids alpha-‐linolenic acid (ALA) and linoleic acid (LA) must come from the diet because they cannot be made by the body.
ALA, an omega-‐3 fatty acid, is converted in the body to the fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
LA, an omega-‐6 fatty acid, is converted to the omega-‐6 fatty acid arachidonic acid (AA)
Thus omega 6 cannot be converted to Omega 3 so the only way to get omega 3 is from the diet
Most diets provide more than 10 times as much omega-‐6 than omega-‐3 fatty acids. There is general agreement that individuals should consume more omega-‐3 and less omega-‐6 fatty acids to promote good health.
What are good sources of ALS,
Good sources of ALA are leafy green vegetables, nuts, and vegetable oils such as canola, soy, and especially flaxseed.
Good sources of EPA and DHA are fish
LA is found in many foods, including meat, vegetable oils (e.g., safflower, sunflower, corn, soy), and processed foods made with these oils. EPA and DHA are metabolized through the same biochemical pathways as AA.
What are EPA and AA precursors for?
EPA and AA are also precursors for hormone-‐ like agents known as eicosanoids
What are eicosanoids responsible for?
Eicosanoids are a group of hormone-like chemicals that regulate many physiological functions
For example inflammation
Redness
Swelling
Pain
Heat (fever)
Is there a desirable mix of omega 3 and 6?
It is not known whether a desirable ratio of omega-‐6 to omega-‐3 fatty acids exists or to what extent high intakes of omega-‐6 fatty acids interfere with any benefits of omega-‐3 fatty acid consumption.
What is the impact of omega 3 on cardiovascular disease?
Impact on cardiovascular disease (CVD):
According to both primary and secondary prevention studies, consumption of omega-‐3 fatty acids, fish, and fish oil reduces mortality and various CVD outcomes such as
sudden death,
cardiac death, and
myocardial infarction.
The evidence is strongest for fish and fish oil supplements.
What is the impact f omega 3 on heart function?
Impact on heart function:
Animal and isolated organ/cell culture studies demonstrate that omega-‐3 fatty acids affect cellular functions involved in ensuring a normal heart rate and coronary blood flow.
Fish oils can lower blood triglyceride levels in a dose-‐dependent manner.
Fish oils have a very small beneficial effect on blood pressure
Possible beneficial effects on exercise capacity in patients with coronary atherosclerosis.
What is the impact of omega 3 on cognitive function?
Impact on cognitive function:
The quantity and strength of evidence is inadequate to conclude that omega-‐3 fatty acids protect cognitive function with aging or the incidence or clinical progression of dementia (including Alzheimer’s disease), multiple sclerosis, and other neurological diseases.
