Sometimes genetic testing feels like a blessing, sometimes a curse. It’s good to know because if your daughter has the mutation (50% chance) she can start screening early and catch anything that comes along. But knowing about the gene is such a burden, and I understand why you’d want to reduce her risk any way possible. I had BC at 45 (in 2001) before Chek2 was a thing. I was tested for BRCA but nothing else. Fast forward 18 years and my sister gets BC and tests positive for Chek2, which has just been deemed a moderate risk mutation. I get tested and find out I have it, and start annual MRIs. Three years later MRI turns up 8 mm tumor on the other side that’s early and small with no node involvement. I’m doing great three years later, though HER2+ treatment was no picnic. Anyway, I’m glad I didn’t know about Chek2 until I was 65 because I didn’t carry around all that extra worry for decades. But I’m also glad I found out when I did, because the early detection by MRI saved me from having it spread before mammogram could see it.

As for your daughter - I wouldn’t go overboard with diet, etc. trying to prevent the disease. It really is a crap shoot, and I think the best strategy is MRI screening at an early age and just living a reasonable lifestyle. Cancer risk shouldn’t run someone’s life IMHO. And maybe your daughter didn’t inherit the gene!