Ah, just been looking at the differences between the oil and the extract, so perhaps will have to give both a try. They mention more types of extracts if you scroll down in the article below
https://www.quora.com/Will-using-gra...e-seed-extract
Jeff Holderness
, President, Psquare Scientific. Doctorate on effects of OPCs on immune cells.
Water-dissolved grape seed extracts: These will contain most of the OPCs from grape seed capsules. However, some of the larger and more active OPCs are not very well dissolved in water and they will not be included. OPCs can also degrade/lose structure more quickly in water. If you do go with a water-dissolved extract, make sure it is a fresh batch.
Grape seed oil: This is great for cooking or use in salad dressings. There may be other health benefits of grape seed oil, but OPCs are not soluble in oil and thus grape seed oil contains only trace amounts of OPCs.
Regardless of which source you choose, make sure to check for OPC content on the bottle. You want to find supplements with 95% or more OPCs for you to have the best chance of activity. You can also check the results from our test of more than 20 different suppliers of grape seed to find the most active in our cell activation assay.