The GMO controversy is such: a litmus test. The conflict is favored by Big Ag, who wants to brand all who disagree with them as Luddites.
On the other side, we have people vehemently opposed to GMOs who understand very little about them.
As usual, the truth is more complicated.
As regards health, the health/gmo connection is weak. First because we don't really have studies asking those questions (intellectual property laws) and second because there is no healthy gmo food. Because, healthy food doesn't grow in enormous, humus stripped, de-mineralized fields sprayed with herbicides and pesticides.
People have the right to trust their intuition, the medical establishment, inherited wisdom, and tarot cards if they want. But a rational thought decision making process can weigh and contrast the ideas given. We can make good decisions.
So pursue healthy food. "Natural" foods and pharmaceuticals are dangerous, but nature has no incentives to hide its perils. Synthetic foods are dangerous, but they are convenient for both consumers and marketers. Remember that nature bats last (there are no silver bullets without hidden side effects) and pursue real food.
Real food is grown in well mineralized, humus rich soil. Real breeds of animals don't need wormers or growth hormones. Real food is usually grown by real people not huge corporations. Real food goes bad if left alone, and real food isn't precooked. If you are worried about health, choose real food, skip the doritos and soda, and gmo or not won't even be a question.
And don't polarize. Find a place to stand where you are comfortable, arriving at decisions that you really believe.