Among the "super foods", after spirulina, chlorella, and super fruit, here is DHA. DHA, a nutritional miracle, is still little known, omega-3 but is becoming more and more followers. Judge instead.
DHA, or docosahéxaéonique acid - not to be confused with DHEA - is one of the three omega-3s necessary for the proper functioning of the body.
Omega-3s are polyunsaturated fatty acids (PUFAs), the precursor of which is alpha-linolenic acid (ALA).
Since this can not be synthesized by the body, needs must be covered by food. In addition, the conversion of ALA to DHA in our body is limited by various factors. But we find DHA in fish and algae.
What is DHA? What is his role ?
DHA:
ensures the fluidity of the membranes;
is essential for brain function (97% of the 14% of omega-3 in the brain is DHA)
participates in the transmission of nerve impulses;
is essential to the eye: in the retina, 93% of omega-3 is DHA (4)
DHA and DHEA
DHA is the most abundant omega 3 in human cell membranes because it is one of the essential elements of cellular functionality.
DHA and omega-3
Omega-3s are so-called essential long-chain polyunsaturated fatty acids (PUFAs n-3), because they are essential for the good health of the body that makes them, but in very insufficient quantities. This is why omega-3 must be provided by the diet, under penalty of significant deficiencies that cause real dangers for the body.
Other fatty acids, such as saturates (AGS), are not "essential".
The three omega-3 constituents of PUFAs:
- Alpha-linolenic acid (ALA): it is absolutely essential because the human body does not know how to make it. He is the precursor of the other two omega-3s. It must absolutely be brought by food.
- Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA): they can be synthesized by our body from ALA. But conversion of ALA to DHA is insufficient to cover needs. It is therefore also necessary to bring DHA by the diet.
Docosahexaenoic acid (DHA) is a long-chain omega-3 polyunsaturated fatty acid that in particular makes up the cells.
Present in large quantities in the brain, DHA plays many structural and functional roles. Thus, it would slow cognitive decline with age.
DHA also has non-specific functions that would also allow it to contribute to a protective effect against neurodegenerative diseases.
The sources of DHA
Plant DHA or animal DHA?
DHA does not exist in all omega-3 sources. There are none in foods of terrestrial plant origin, but there are those of animal, terrestrial or marine origin.
To simplify, to obtain DHA, there are two main possibilities: either fish oil (animal DHA) or extracts of micro-algae (marine plant DHA).
DHA of animal origin
Omega-3s of terrestrial animal origin are concentrated in offal (liver, kidney, brain, etc.). But they are much less consumed since the different health crises (mad cow, ...).
Omega-3s of marine animal origin are present in fish oils, especially in oily fish (mackerel, herring, salmon). They particularly like to eat plankton and algae that contain ALA, and convert it into DHA and EPA in larger amounts than the human body can.
We just need to eat these fish to benefit from a good intake of omega-3, especially DHA.
But it is not so simple ... Fish oil has the risk of containing residues of heavy metals such as mercury, PCB or pesticides. These pollutants accumulate in fact in fish fats. Thus, the richest omega-3 fish have the highest risk factor for contamination.
Another concern: it takes half a ton of fish to get a liter of oil. The production of DHA from fish is therefore not environmentally friendly. It helps to compound the problem of overfishing in our oceans against which fishing quotas are trying to fight.
Another marine animal source of DHA is phytoplankton and krill. But here too, the disappearance of this natural food for marine animals would contribute to the extinction of many species.
DHA of plant origin
Omega-3s of terrestrial vegetable origin are present in rapeseed, nut, soya, or, of course, margarine oils containing these vegetable oils.
Spirulina, chlorella
There are also sources of omega-3 marine plant origin, and especially DHA: these are micro-algae, such as Spirulina, Chlorella, and Schyzochitrium. They have many advantages:
- An ecological culture: advances in biotechnology now make it possible to cultivate micro-algae in a bioreactor, in a controlled environment and 100% clean, with no risk of residues.
- CO2 reduction: the production of one tonne of microalgae absorbs 2.2 tons of CO2, thus reducing the carbon footprint.
- An oxygen production: micro-algae have been involved in the production of oxygen since their appearance 3.5 billion years ago.
- Important concentrations: the concentrations of DHA in oils extracted from micro-algae are higher than those of fish oils.
Through its preservation of biodiversity and its guaranteed sanitary quality, it is this category of DHA of marine vegetable origin that consoGlobe has selected for its shop.
It is a pure DHA, derived from a micro-algae type Schyzochitrium, without toxic substance, and durable and non-allergenic.
Why take DHA?
Omega-3 fatty acids are all good for your health, but especially docosahexaenoic fatty acid, DHA.
DHA is important throughout life:
- it allows a greater membrane fluidity,
- it participates in neurotransmission and synaptic plasticity at the cerebral level,
- it influences the carbohydrate metabolism thus regulating the glucose supply to the brain,
- it promotes neurogenesis (creation of new neuronal cells),
- it contributes to neuronal survival.
EFSA has found other virtues at DHA, based on the many studies on the subject:
- it reduces the blood pressure,
- it reduces the blood concentration to triglycerides,
- it contributes to the development of the brain. Several studies show that DHA stimulates, even in low doses, the production of the LR11 protein that naturally protects the brain.
- it contributes to the development of the eye.
The action of DHA is so decisive that it has also been shown to be able to slow the progression of Alzheimer's disease in mice (La Ferla study, for Martek Bio sciences Corporation, 2006). These results suggest that people with a family history of Alzheimer's disease would benefit from eating a diet rich in omega 3.
Omega-3s are effective in preventative mode
An Italian study conducted on 7,000 patients and reported by Que Choisir shows that the chances of survival for subjects at high cardiovascular risk is a little higher if they follow a regular treatment based on omega 3 (1 g / day) only for those who only use a placebo. This is not the case of the conventional drug pathway with statins (Rosuvastatin 10 mg / day) that provide nothing compared to placebo.
The health benefits of DHA in details
DHA and the nervous system
Our brains and neurons need DHA every day because it is the most abundant polysinsaturated fatty acid in the brain.
- DHA is a structural and functional element of the brain of all cell membranes and neurons. DHA is incorporated into the nervous system during fetal life, in the third trimester of pregnancy, and during the first years of life.
- DHA is an essential constituent of the membranes of our cells, especially neurons in the brain.
DHA and the cardiovascular system
- More than 30 years ago, it was noted that Eskimos, and the Japanese (especially Okinawa Islanders), heavy consumers of fish, had very little myocardial infarction.
- According to EFSA, studies with DHA have shown a decrease in triglycerides and an action on blood pressure.
DHA and eyes
DHA is one of the major membrane constituents of retinal cells.
DHA and the child's brain
- DHA has a beneficial effect on vision.
Omega-3s, especially DHA, are crucial for the growth of children and their brains, especially during the fetal period. DHA is a key nutrient for a balanced diet in the 3rd trimester of pregnancy, for the baby, but also for the mother.
After birth and during the infancy of the baby, omega-3 and especially DHA continue to play important roles for the growth and development of the child. It is therefore advisable for young mothers to practice breastfeeding, since breast milk is naturally very rich in omega-3 and omega-6).
And for those who are not breastfeeding, let them reassure themselves: a lot of milk-based infant formula contains it in synthetic form. Manufacturers have requested authorization to add the health claim for DHA to infant foods, including follow-up formula, for children 6 to 12 months of age. EFSA has given the following statement to baby food containing DHA: "contributes to the normal visual development of infants up to 12 months of age".
DHA and diet: how much to consume?
Recommended daily intake of DHA
............. ALA / DHA ...... ..For adults and seniors: the DHA pool must be maintained by our diet.
. Women: 1,600 mg / 250 mg
. Men: 2,000 mg / 250 mg
Our intake of DHA is sorely lacking in our modern diet. To cover the daily recommended contributions, the National Health Nutrition Program recommends eating fish at least twice a week.
But often, that's not enough. The DHA is too often lacking in our plate, all food surveys show: our consumption of omega-3 is far from the recommended intake.
Foods bringing omega-3s *
Foods that are naturally rich in omega-3s are quite limited: they are mainly rapeseed, nuts, and soybean oils, for ALA, and fatty fish for EPA and DHA. In fact, our intake of ALA is 2 to 10 times lower than the recommendations, according to consumer surveys. As for the contributions in EPA and DHA, there are great individual differences, and in some cases they can be almost null.
Food / Portion /% ANC **
- Walnut oil: 10 ml / 60% (ALA)
- Rapeseed oil: 10 ml / 40% (ALA)
- Dry walnuts: 20 g / 60% (ALA)
- Flaxseed: 10 g / 100% (ALA)
- Cooked salmon: 100 g / 800% (DHA)
- Spinach: 150 g / 10% (ALA)
- OMEGA 3 DHA : 1g / 100% * (DHA) (2)
The nutritional values of the DHA
- Caloric value for 100 gr: 3616 Kj / 861 Kcal
- Caloric value per capsule 30.8 Kj / 7.31 K cal
- Protein 0 g / 0 mg
- Carbohydrates 6.7 g / 36 mg
- Lipids 92.4 g / 483 mg
- Fibers 4.4 g / 23 mg
- DHA 38.21 g / 200 mg
- Omega 3 41.39 g / 216 mg
- Omega 6 17.54 g / 92 mg
- For 100 g / per capsule
DHA and pregnant or lactating women
Recommended daily intake of DHA: 2000 to 2200 mg / 250 mg
The fatty acid composition of the amniotic fluid and breast milk is very dependent on the diet of the pregnant and lactating woman. A pregnant woman has her own reserves of omega-3s, but these are not necessarily sufficient to meet her needs and those of the fetus.
It is therefore essential for every woman of childbearing age to take care of her omega-3 diet, especially DHA, because these are essential to ensure good brain development for her baby.
The positive effects of DHA provided by phospholipids:
The DHA provided by phospholipids has:
- better accretion in the cell membranes,
- better resistance to oxidation,
- a maintenance of the arachidonic acid / DHA ratio in the membranes,
- no gastric reflux (compared to forms of fish oil intake) when ingested (dietary supplement, oral cosmetic),
- a New Food status since June 2010 (see the AFSSA website).
Physiological effects observed (mechanisms) following the intake of DHA
- Improvement of breathing (microcirculation, patent of use filed in Europe and North America).
- Best recovery at the sportsman (micro-circulation).
- Better visual acuity in the elderly person: micro-circulation, accretion of DHA in the retina which is the richest tissue in DHA (1),
- Improvement of the coat in animals and hair regrowth.
- Improvement of scarring in animals, topically in the form of liposomes.
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