I have always been sceptical about this type of blood test (es https://omegaquant.com). I would be interested in your opinion. Could they be a useful tool for assessing e.g. EPA/DHA intake in subjects on a vegetarian/vegan diet?
I have used this type of test only once in a young patient who recently had a myocardial infarction. After this cardiovascular event the patient decided to become a vegan but to eat occasional oily fish only for health reasons.
I thought the test in this type of patient might be useful in deciding whether to start omega-3 supplementation.