By now, the benefits of breastfeeding are pretty well known—it provides complete nutrition for baby, can increase baby’s intelligence, reduces the risk of developing allergies—and more benefits are being discovered everyday, like how breastfed babies are less likely to become obese adults.

If you are breastfeeding or are planning on it, you may want to know how your diet—even foods that are good for you—may cause tummy upset for your little one. Eating onions, garlic, broccoli and peppers can cause gas and fussiness in baby. Dairy products in your diet can cause an allergic reaction, including diarrhea, a rash, cough or congestion. Citrus fruits can cause fussiness, vomiting, skin rashes and sniffles.

Of course, this doesn’t mean cutting these foods out altogether as they are healthy for you, but if they seem to be causing your baby upset, you can cut back on them one at a time until you find the culprit and limit that one while breastfeeding.