The phrase "tummy issues" means having problems with your stomach, such as feeling sick, having pain, or experiencing digestion troubles. Full definition
«I find that pets with tummy issues tend to benefit greatly after just a few doses of a probiotic supplement,» she says. (rodalesorganiclife.com)
He really seemed to love it too, until he started having a lot of tummy issues after eating! (babygaga.com)
You can get a lot of popular dried fish treats which are low in fat but for some reason they can cause tummy issues too, so you really need to be careful. (cavaliermatters.org)