The Fat Profile
Grape seed oil is mostly polyunsaturated fats (PUFA) with only small amounts of saturated and monounsaturated fats. This makes it a terrible cooking oil because PUFAs are highly unstable, which means they are likely to oxidize when exposed to heat and light. Consuming oxidized fats should be avoided because it results in oxidized cholesterol in our blood, and that’s the stuff that will latch onto the insides of our arteries, causing inflammation and plaque build-up.
Omega-6 vs. Omega-3 Fats
As if that weren’t bad enough, the PUFAs contained in grape seed oil are almost entirely omega-6 fats, a type of PUFA that is particularly inflammatory. One of the main problems with the current Standard American Diet (SAD) is the fact that it is extremely high in omega-6 and low in omega-3 fats. Ideally, one should maintain a balance of at least as many omega-3 as omega-6 fats, if not more.
Mark Sisson rejected grape seed oil as a healthy option in his guide to oils.
