Embed Size (px)
Citation preview
OMEGA 3 AND
6 FATTY
ACIDS
Benefits of Long Chain Omega-3 Fatty Acids EPA, DHA):
What Does “Omega-3” Mean? The term “omega-3” or “n-3” indicates
that the first double bond is located at the third carbon from the methyl end of the fatty acid chain.
The long-chain omega-3s from marine sources are EPA and DHA, with 20 and 22 carbons.
There are also plant sources of omega-3 fatty acids with 18 carbons.
An abundance of evidence strongly suggests that increased intakes of long chain omega-3 fatty acids can markedly reduce the risk of heart disease.
The omega-3 fatty acids believed to be largely responsible for these effects include EPA and DHA.
These “good fats” are naturally present in some types of fish and in other marine organisms such as algae, and they are also readily available in purified form in dietary supplements
THE LONG-CHAIN N-3 FATTY ACIDS FOUND IN FISH MAY REDUCE THE RISK OF SUDDEN DEATH FROM CARDIAC DISEASE
The researchers suggest that omega-3 fatty acids may protect against death from heart disease by decreasing the Heart’s tendency to arrhythmia.
The most important finding is of a reduction in sudden death from ventricular fibrillation and tachycardia.
Omega-3 fatty acids also reduce the tendency to thrombosis (formation of blood clots), and thus help prevent myocardial infarction.
EPA and DHA also have several actions that inhibit the development of atherosclerosis.
While these fatty acids do not lower plasma cholesterol levels, they do have a substantial triglyceride-lowering effect and also raise levels of HDL (“good” cholesterol).
Now in the present scenario omega-3 fatty acids are regarded or have the status of natural food
Ѡ – 3 FATTY ACIDS
Docosahexaenoic acid (DHA): 22 carbons and six double bondsEicosapentaenoic acid (EPA):20 carbons and five double bonds
Alpha-linolenic acid (ALA):18 carbons and three double bonds
MOST IMPORTANT OMEGA -3 FATTY ACID DOCOSAHEXAENOIC ACID (DHA)
Docosahexaenoic acid (DHA) is the most important member of the
Omega – 3 Fatty Acid
WHY ? Because it is a primary
structural component of the human brain, cerebral cortex, skin, sperm, testicles and retina
It can be synthesized from alpha-linolenic acid or obtained directly from maternal milk or fish oil.
STRUCTURE OF DHA DHA's structure is a
carboxylic acid (-oic acid) With a 22-carbon chain Docosa- is a Greek word for 22 With Six (hexa-) cis
double bonds (-en-) with the first double bond located at the third carbon from the omega end.
CERVONIC ACID Its trivial name is cervonic acid Its systematic name is all-cis-docosa-4,7,10,13,16,19-
hexa-enoic acid, and its shorthand name is 22:6(n-3) in the nomenclature of fatty acids.
Cervonic acid, DHADO(4Z,7Z,10Z,13Z,16Z,19Z)-DOCOSA-4,7,10,13,16,19-HEXAENOIC ACID
Properties
Molecular formula C22H32O2
Molar mass 328.488 g/mol
Density 0.943 g/cm3
Melting point −44 °C (−47 °F; 229 K)
SOURCES OF DHA Cold-water oceanic fish oils
are rich in DHA. Most of the DHA in fish and multi-cellular organisms with access to cold-water oceanic foods originates from photosynthetic and heterotrophic microalgae,
DHA is also commercially manufactured from microalgae:
Crypthecodinium cohnii and another of the genus Schizochytrium.
DHA manufactured using microalgae is vegetarian
Some animals with access to seafood make very little DHA through metabolism, but obtain it in the diet.
However, in strict herbivores, and carnivores that do not eat seafood, DHA is manufactured internally from α-linolenic acid
Α-Linolenic acid also called ALA is a shorter omega-3 fatty acid manufactured by plants (and also occurring in animal products as obtained from plants).
PRODUCTION DURING METABOLISM OF EPA & DHA
Limited amounts of eicosapentaenoic and docosapentaenoic acids are possible products of α-linolenic acid metabolism in young women and men .
DHA is difficult to detect above dietary background in males compared with females
This shows the importance of DHA production for the developing foetus and healthy breast milk. .
DHA is richly supplied during breastfeeding, and DHA levels are high in breast milk regardless of dietary choices.
CONCENTRATION IN BREAST MILK DURINGPREGNANCY AND LACTATIONDHA concentrations
in breast milk range from 0.07% to greater than 1.0% of total fatty acids, with a mean of about 0.34%.
DHA levels in breast milk are higher if a mother's diet is high in fish.
DHA IS CONSTITUENT OF THE CENTRAL NERVOUS SYSTEM
DHA is the most abundant omega-3 fatty acid in the brain and retina.
DHA comprises 40% of the polyunsaturated fatty acids (PUFAs) in the brain and 60% of the PUFAs in the retina.
Fifty percent of the weight of a neuron's plasma membrane is composed of DHA.
DHA deficiency is associated with cognitive decline of Phosphatidylserine(PS) controls apoptosis, and
Low DHA levels lower neural cell PS and increase neural cell death
DHA levels are reduced in the brain tissue of severely depressed patients.
Higher DHA levels in middle-aged adults is related to better performance on tests of nonverbal reasoning and mental flexibility, working memory, and vocabulary
BELOW-NORMAL LEVELS OF DHA HAVE BEEN ASSOCIATED WITH ALZHEIMER'S DISEASE
Alzheimer's disease and decline of mental health
Preclinical studies indicate that DHA improves memory, can slow the progression of Alzheimer's diseas
DHA deficiency likely plays a role in decline of mental function in healthy adults
high intake of DHA was associated with reduced risk for developing Alzheimer's disease and Parkinson's disease
Consistent with DHA being the most abundant omega-3 fatty acid in the brain.
Therefore Neuro protective effects of dietary DHA cannot be ignored
DHA modulates the carrier-mediated transport of choline, glycine, and taurine.
It functions as the delayed rectifier potassium channels and the response of rhodopsin contained in the synaptic vesicles, among many other functions.
A low level of DHA is also spotted in patients with Retinitis pimentosa
PROTECTIVE EFFECTS OF DHA It is now considered so important to
brain and eye development that DHA is included in most infant formulas.
Lastly, in preliminary research, it was found that a diet rich in DHA might protect stroke victims from brain damage and disability and aid in a speedier recovery.[
Accordingly, dietary administrered DHA reduces stroke-induced neuroin flammation in animal models.[59]
FORMATION OF ACROSOME DHA is very likely important in the
formation of the acrosome, an arc-like structure on the top of sperm, which is critical in fertilization because it houses a variety of enzymes that sperm use to penetrate an egg.
Because humans and other mammals are able to make their own DHA from other fatty acids, DHA deficiency is not common. But, if that DHA-synthesizing enzyme is defective, it could lead to problems with infertility.
IN EPILEPSY AND COLON CARCINOMA The use of DHA by persons
with epilepsy could decrease the frequency of their seizures.
In mice, DHA was found to inhibit growth of human colon carcinoma cells, more than other omega-3 PUFAs.
SLOWS DOWN AGING
A new study found that higher intake of DHA was associated with slower rates of telomere shortening, which is a basic DNA-level marker of aging.
DHA & EPA LOWER INFLAMMATORY CYTOKINES
One study found that fish oil higher in DHA than EPA lowered inflammatory cytokines, such as IL-6and IL-1β associated with neurodegenerative and Autoimmune diseases
They note the brain normally contains DHA, but not EPA, though both DHA and EPA plasma concentrations increased significantly for participants
NUTRITION
Ordinary types of cooked salmon contain 500–1500 mg DHA and 300–1000 mg EPA per 100 grams. Additional top fish sources of DHA include
tuna, bluefish, mackerel, swordfish, anchovies, herring, sardines, and caviar.
Diets that consist of high doses of omega-3 fatty acids help prevent strokes. There are fewer strokes in countries where people consume high amounts of omega-3 fatty acids, such as Japan and Sweden
DISCOVERY OF ALGAE-BASED DHAIn the early 1980s,
NASA sponsored scientific research in search of a plant-based food source that could generate oxygen and nutrition on long-duration space flights.
This research led to the development of an algae-based, vegetable-like oil that contains two essential polyunsaturated fatty acids, DHA and ARA (arachidonic acid), which can now be found in health supplements.
USE AS A FOOD ADDITIVE
DHA is widely used as a food supplement
It was first used primarily in infant formulas. In 2004, the US Food and Drug Administration endorsed qualified health claims for DHA.
2007 DHA-fortified dairy items milk, yogurt, cooking oil started
to appear in grocery stores.
STUDIES OF VEGETARIANS AND VEGANS
While .there is little evidence of adverse health or cognitive effects due to DHA deficiency in adult vegetarians or vegans, fetal and breast milk levels remain a concern
Vegetarian diets typically contain limited amounts of DHA, and vegan diets typically contain no DHA.
Vegetarians and vegans have substantially lower levels of DHA in their bodies, and short-term supplemental ALA has been shown to increase EPA , but not DHA.
However, supplemental preformed DHA, available in algae-derived oils or capsules, has been shown to increase DHA levels.
DHA is believed to be helpful to people with a history of heart disease.
For premature infants, and to support healthy brain development especially in young children along with supporting retinal development.
Some manufactured DHA is a vegetarian product extracted from algae, and it competes on the market with fish oil that contains DHA and other omega-3's such as EPA.
Both fish oil and DHA are odorless and tasteless after processing as a food additive.
THANK
YOUDR.GEETA
JAISWAL
![Omega 3 Fatty Acids, Gestation and Pregnancy [Autosaved]](https://img.pdfslide.us/doc/110x75/55cf923b550346f57b94c951/omega-3-fatty-acids-gestation-and-pregnancy-autosaved.jpg)
