Hi, the fish oil is a natural blood thinner, and I was told to stop them 10 days prior to surgery. I have just recently fallen and broken my arm in several places, and because I am on fish oil, I have really bled badly into the tissues around the fractures. The bruising is still bad and this happened 3 weeks ago. Things like Asprin can also thin your blood, so listen to your doctors. I also agree with Lorraine about the immune boosters and chemo. Depending on what they are, some will counteract what the chemo is trying to do, so when in doubt, always discuss first with your oncologist, and understand why he doesn't want you to take certain supplements. Love Chris xx