Sweat is the natural way for your body to regulate its temperature. But perspiration has its problems. It picks up whatever is on your skin – dirt, dust, grime. If you let it settle on your skin, it can cause more irritation, so be sure to dry yourself off or do a quick wash as soon as possible after sweating.
If you have sensitive skin or a condition like eczema, sweat can cause burning and itching. And because there are so many opportunities to sweat in the summer, it's essential you mitigate times where you'll sweat. On the hottest of days, consider combining trips outside, wear loose clothing made of cotton, and again, stay hydrated.
And if you're wearing sunscreen with petroleum or mineral oil, you could accidentally block your pores, which can block sweat from escaping your skin. That's when acne, or worse, an angry heat rash, can appear.
So be aware of increased perspiration during the summer. Of course, you could try to shower every time you get sweaty, but even that can be problematic.