If you're going to introduce legumes into your diet you need to know about lectins, particularly phytohaemagglutinin (PHA). Beans in general - and especially kidney beans - are high in this. It can cause extreme stomach upset.
You can reduce lectins by soaking beans for a few hours or overnight - and *discarding* the soak water.
If you get a new Instant Pot for Xmas and decide to make red beans in it - BEWARE. The recipe booklet will tell you you can cook unsoaked kidney beans. Don't do that. Rinse, soak, discard water - now you can make the dish. PHAs are also broken down by cooking, so hours on the stove gets rid of a lot of it.
FWIW, I got an instant pot specifically for cooking legumes. I still soak / discard. It's still a 'win' (easier to control texture plus no major stove mess to clean up).
And yes, there are lectins in a lot of the plant based foods we eat (even gluten is a lectin), but like everything else, the poison is in the dose.
More on PHA: https://en.wikipedia.org/wiki/Phytohaemagglutinin