I grabbed the first google result that showed up and it says grape seed oil is 70 percent polyunsaturated fat. Omega 6 polyunsaturated fat is inflammatory in large amounts, so not looking good for this product. Fairly high omega 6 polyunsaturated fat in sesame seed oil, too, although it's so strongly flavored that who would use very much of it, I just add a little for flavoring in some dishes. For making home made mayo and dressings I've found avocado oil is mild in flavor and much lower in polyunsaturates. EVOO is a good oil but I find the taste too strong for mayo. Coconut is a good healthy oil but too stiff when cooled for stuff like mayo making.