There has been a lot of chatter on the Internet that type 2 diabetics who eat soy products can reverse the disease. Like a lot of the chatter on the Internet about type 2 diabetes, it's an exaggeration based on an important fact.
The bottom line about soy and type 2 diabetes is that if you are newly diagnosed with type 2 diabetes, and your problem is something called insulin resistance rather than deterioration of the insulin-making cells of your pancreas, soy products actually do help. There seem be chemicals in soy, especially fermented soy products like miso, that protect the insulin-making beta cells from attack by free radicals and by the immune system.
That doesn't mean you can eat a nibble of tofu and then gallon of ice cream and expect everything to be hokey-dorey. You still need to deal with the basic problem, insulin resistance. But if you DO deal with insulin resistance, then soy can help you get rid of type 2 diabetes practically as soon as it starts.
If you have had type 2 diabetes for more than a year or two, then the benefits of soy are a lot less clear. And there is no benefit in the highly processed soy proteins and fake meats that used to be so popular among vegans.
Moreover, you don't have to eat huge amounts of soy. As little as 15 grams (half an ounce) may be enough. But that little bit of soy, along with a lot of dietary restraint, may be what you need to get rid of your early-stage type 2 diabetes for good.
Kwak JH, Lee JH, Ahn CW, Park SH, Shim ST, Song YD, Han EN, Lee KH, Chae JS. Black soy peptide supplementation improves glucose control in subjects with prediabetes and newly diagnosed type 2 diabetes mellitus. J Med Food. 2010 Dec;13(6):1307-12.