Though dozens of countries around the world require genetically modified food to be labeled, the US is not one of them. In the absence of lables, here are our best tips for avoiding GMOs when you shop:

1. Look for the Non-GMO Project label: The Non-GMO Project label provides consumers with independent, third-party assurance that a product contains no GMOs. The Project tests high-risk ingredients in the products that bear its label, to ensure that they contain less than 0.9 percent GMOs (allowing for low levels of unintentional contamination).

2. Be wary of unverified non-GMO claims: A company may legally label its products as being GMO-free without having to perform testing or otherwise prove to a third-party that is the case.

3. Buy organic: USDA-certified organic products cannot intentionally contain GMOs. The USDA doesn’t require testing for GMOs, so accidental contamination of organic products may occur.

4. Avoid high-risk ingredients: These nine ingredients are all considered high-risk for GMOs. Avoid non-organic versions of these, whole and in ingredient lists.

5. Avoid non-organic processed foods: The list of hidden GM ingredients in processed foods is long, ranging from ascorbic acid to xanthan gum. Get a full list of ingredients to avoid in the Non-GMO Shopping Guide.

6. Look at the price-look-up (PLU) sticker: If it shows a four-digit number, the produce is conventionally grown without GMOs, and a five-digit number beginning with “9” means 100-percent organic. Technically, a five-digit number beginning with “8” means it is genetically modified, but since such labeling is voluntary, Consumers Union’s Dr. Michael Hansen says he doesn’t know of a single example of such a label existing.