Word’s out about the dangers of taking some other meds while on antiretroviral combos. Some foods, too, can wreak havoc on an HIV drug’s effectiveness—you’ve likely been warned to avoid grapefruit juice, which can inhibit the ability of a crucial enzyme (cytochrome P450 3A, or CYP3A) to break down both protease inhibitors and non-nucleoside reverse transcriptase inhibitors. Well, the bad news is, grapefruit juice is just one culprit. There are hundreds of fruits and vegetables that contain CYP3A-inhibiting compounds (and so may increase a drug’s toxicity and side effects). But the good news is that of those studied so far, few harbor levels high enough to alarm.

According to chemist and nutrition researcher Chester Myers, PhD, pill-poppers should be wary of garlic, blackberries, black cherries, broccoli, elderberries, cocoa, kale, onions, red wines, tea, blueberries and apples. Not that you have to purge these from your diet immediately and entirely. “If you’re having drug side effects,” Myers says, “avoid large servings of any of these foods. And don’t combine more than a couple at any meal.” And stay tuned: Future research may augment or diminish these culinary cautions. One final worry for your list: The opposite effect—inducing, or speeding up, CYP3A’s work—can also limit a drug’s effectiveness by clearing antiretrovirals from the body too quickly. But so far, the only food-derived compounds that have been found to do this are in licorice and one of its components, glycyrrhizin.