Soy can cause issues in people who are sensitive to phytoestrogens (so I'd think breast issues would be more likely than prostate issues) but for people without such sensitivities, there shouldn't be a problem.

Soy is also an issue for people on synthetic thyroid hormones, as it binds to the hormone and prevents its uptake in the body.

I avoid eating much soy because the phytoestrogens are bad news for a hypercoagulability disorder I have.

Heterozygous Factor V Leiden here, two clots in my right leg (calf and thigh) although they were likely from causes other than the disorder (BC pills for the first, and an injury for the second). I was on warfarin for a while but it does NOT play nicely with my body, so I'm not on it anymore. I treat with diet and lifestyle, and have been clot-free since 2008.

I'll eat soy when it occurs as a flavoring, like in Asian food (which I love) but I'm almsot kind of glad to have an excuse not to eat tofu, as I never particularly liked it anyway.

I was on the pill when I had my first clot at 37. I'd also been exposed to a lot of secondhand smoke during that timeframe, and then pulled (and probably micro-tore) a muscle in my right calf. Got a DVT there as a result, though it didn't migrate as I was treated in time.

Got off the pill, spent six months on warfarin, felt kind of crummy but didn't make the connection at the time between that and the warfarin. Was taken off warfarin and went about my business.

Injured my left knee several years later and spent time in physical therapy for it. Was still rehabbing the knee when I broke my right ankle, and found walking on crutches difficult because my knee didn't want to cooperate fully so I wound up in a wheelchair for several weeks. Between the broken bone (which can potentially cause a clot in anyone) and being wheelchair-bound (ditto), I developed a DVT in my right thigh. This time I was tested for abnormal clotting factors and they discovered the FVL. I spent another five months on warfarin, but this time I felt so damn lousy that I started looking up why. Turned out that I was experiencing a whole slate of side-effects from the medication, and I went to my doc and told him I wasn't willing to take it anymore. Interestingly enough, it didn't seem to even be doing what it was supposed to all that well anyway as they could never get my prothrombin time up where they wanted it no matter how high they raised my dose, so keeping me on it would've been something of an exercise in futility.

I keep tabs on my diet instead, balance my intake of anti-clotting foods and supplements to offset my intake of foods containing Vitamin K (I love spinach, for example, but it has a ton of K so I have to offset that with capsaicin and garlic, which I fortunately also love) and thus far I'm doing fine. I take grapeseed and horse chestnut, both of which seem to have really helped with things like swelling in the right leg -- I rarely have to wear a pressure stocking now. And I'm careful to avoid sitting still for long periods, etc.