Why not just eat blackcurrants rather than wasting money on blackcurrant oil capsules? Blackcurrants are a good source of vitamin A, some of the B vitamins, vitamin C, iron and (antioxidant) polyphenols - all of which have health benefits; blackcurrant seeds (from which I guess the oil is extracted) contain omega-6 fatty acids which are also regarded as beneficial. However the best way of ensuring a beneficial intake of these sorts of nutrients is to eat a wide range of fruit, vegetables and nuts as part of your daily diet!
Eric from GuitarLoot
Renaissance and Baroque freak; classical guitars by Lester Backshall (2008), Ramirez (Guitarra del Tiempo 2017),
Yamaha (SLG 130NW silent classical guitar 2014).