I once had to deal with this issue with an employee who happened to be a very prickly minority. His problem was not body odor, it was too darn much cologne. He was a heavy smoker, and would bathe himself down with cologne after an (unauthorized) smoke break. We dealt with it for a long time. He implied, when I tried to discuss this with him, that I was saying all people of his race stink. It was a circular argument. Finally we sort of resolved it as he got over feeling mistreated and wanting to hit at us for the aggrivation privilege.
I do want to say though, that if this is a recent thing, like since Christmas, it might be that your employee has changed cosmetic and hygiene routines. Lots of stuff is coming up lately about how there is no need to shower daily (wildly disagree here!) and that your skin does so much better if you do not. And that crazy stuff they have just started selling and advertising heavily lately that's supposed to be deodorant for your whole body, including those parts they hint about and don't quite mention. ...Well, that stuff is deodorant, NOT an antiperspirant. And I had to learn myself during adolescence, and have had to pass on and give many lectures to smelly teenagers, deodorant doesn't always work. Antiperspirants are often what is required, some people, depending on body chemistry and what they eat, etc. have a stronger body odor than others, and a sweet little deodorant does NOT do the trick for some of us.
Natural is not always nicer. I had some idiot try to tell me when I had breast cancer that it could be from the antiperspirants I had used all my life, "They cause cancer, you know!" But I wouldn't be shy about saying something. It might "hurt her feelings" but I'm sure you're not the only one who has noticed.