Slow carb means you don't eat anything that quickly converts to sugar. Starch is sugar. Bread, potatoes, rice (those are the main ones) - they all convert fairly quickly to sugar. Brown rice is better than white, but apparently brown can still breakdown pretty quickly.
So if you're eating slow carb that means veggies, beans, and meat and fish if you eat meat and fish. If you don't eat animals, you're basically left with greens and beans. Fruit is a tricky category because it can spike the blood sugar.
Generally its probably pretty obvious that its better to eat slow or low carb foods whenever possible. But it's hard for some people who want to eat slow carb vegan. Eggs are pretty important for getting protein, but if you're vegan or want to be you can't eat eggs. So you only have beans left, really.
I think the main thing is that you can't eat junk. Maybe you don't need to go all out and restrict your diet, but at least don't eat a lot of bread, even brown bread - and limit your rice, too. It's sad isn't it? It just comes down to basically eat salads all the time!:)