What are omega-3s?
Omega-3s are a family of polyunsaturated fatty acids. Three of them have shown significant activity in humans: alpha-linolenic acid (ALA, 18:3 ω-3), eicosapentaenoic acid (EPA 20:5 ω-3) and docosahexaenoic acid or (DHA 22:6 ω-3). Only ALA is considered essential (and must therefore be provided by the diet), because from it the body can (in theory) synthesize the other two.
Omega-3s are important because they are inserted into the phospholipids that make up our cell membranes. The fact that these fatty acids are unsaturated gives these membranes more flexibility, greater fluidity and better chemical exchanges with the outside. This fluidity is particularly important in blood vessels and neurons.
Signs of a deficiency
1. Dryness and irritation of the skin
A deficiency in omega-3 could be detected in people who suffer from dryness and irritation of the skin. Indeed, omega-3 supplementation has been found to improve these symptoms, suggesting deficiency..
Moreover, some more serious skin conditions also seem to be improved by supplementation. For example, a study of people with atopic dermatitis showed that supplementing with hemp oil for 20 weeks daily reduced dryness and itching, allowing participants to reduce their need for medication.
Similarly, the condition of psoriasis sufferers could be improved by taking an omega-3 supplement.
Diet affects mental health, in fact studies have compared the Mediterranean diet and the traditional Japanese diet to a typical “Western” diet and have shown that the risk of depression is 25 to 35% lower in those who follow a traditional diet. Among the parameters that differentiate these diets is the quality of the fats and particularly the omega-3 content of the diet.
Several quality studies have already shown that omega-3 supplementation could improve depression (6) and at the same time other studies have shown that a satisfactory level of omega-3 helps to maintain a feeling of well-being and satisfaction.
3. Weight gain
There is little evidence to show that weight gain is directly linked to a deficiency in omega-3. Nevertheless, several studies have shown that omega-3 fatty acids promote lipolysis, i.e., the availability of fat for energy, an interesting asset to facilitate fat loss during a diet.
Thus, in a clinical trial conducted on about forty people, the group that received olive oil lost an average of 5.8% of its weight, compared to 7.2% for the group that took omega-3.
An observational study of over 23,000 people suggests that high intakes of omega-3 fatty acids are associated with an attenuation of the genetic association with long-term weight gain.
4. Dry eyes
Omega-3 fatty acids play a role in eye health, including maintaining eye moisture with tear production.
There are multiple causes of dry eye syndrome, so omega-3 deficiency alone cannot be responsible. On the other hand, as a recent meta-analysis that gathered the results of 17 clinical trials with more than 3,000 patients indicates, supplementation is effective and very useful in combating dry eye as a symptom.
5. Dry, brittle and fragile hair
Just as omega-3 fatty acids help retain moisture in the skin, they also help nourish the hair. Changes in hair texture, integrity and density can indicate low omega-3 status.
A 6-month study supplemented 120 participants with omega-3 daily. At the end of the study, researchers observed reduced hair loss and increased hair density compared to the control group.
How to confirm a deficiency?
By deduction, if the consumption of foods that are sources of omega-3 is low (fatty fish, seafood, rapeseed oil, nuts) we can suspect an omega-3 deficiency even if no clinical signs are present. In addition, the consumption of processed foods rich in omega-6 can also indicate an omega-3 deficiency. Indeed, an excess of omega-6 hinders the transformation of ALA into EPA and DHA. Thus, vegetarians and vegans are a population at risk of deficiency.
To confirm a deficiency through blood tests, laboratories measure the fatty acids contained in the red blood cells. They reflect the diet followed during the 3 months preceding the analysis and allow to detect an imbalance in the diet.
How to compensate for a deficiency?
More than the absolute intake of omega-3, the most important thing for the body is to ensure a good omega-6/omega-3 ratio. It is essential to reduce the intake of omega-6, which means reducing the proportion of ultra-processed foods, avoiding cooking with sunflower oil, corn oil, grape seed oil, palm oil and margarines.
By consuming foods rich in ALA on a daily basis, one ensures, a priori, the synthesis of other omega-3 (it seems, however, that the conversion is not always done well). To do this, it is necessary to include in one’s diet oils rich in omega-3 (rapeseed oil, flaxseed oil, walnut oil, perilla oil), as well as nuts and seeds (walnuts, chia seeds, flaxseed, hemp seeds).
For a good intake of EPA and DHA fatty acids (which are the forms of omega-3 directly available to the body), be sure to eat fatty fish (salmon, herring, trout, mackerel, sea bass, sardines) twice a week, preferring small fish at the beginning of the food chain, which contain fewer heavy metals. Otherwise, and in particular in the absence of fish consumption, it will be necessary to make sure to consume animal products fed with grass and flaxseed, the Bleu-blanc-cœur network and certain organic products (to be verified) ensure this quality of products.