Q: Should you line the pan with aluminum foil, or would it be healthier to switch to parchment paper?
A: Yes, when roasting vegetables, parchment paper is better than foil. Recent research in the International Journal of Electrochemical Science suggests that when we use aluminum foil during cooking, some aluminum leaches into food. Leaching increases with higher heat (roasting and broiling) and acidity (tomatoes, vinegar, vitamin C–rich produce).
Is aluminum leaching into food bad? Maybe. The average person consumes between 7 and 9 milligrams of aluminum each day through diet. The Food and Drug Administration considers such levels generally safe, and the Alzheimer’s Association concludes that this normal exposure to aluminum is not a significant risk factor in Alzheimer’s disease.
However, the Center for Disease Control’s Agency for Toxic Substances & Disease Registry suggests that consuming higher levels of aluminum than average may be linked to nervous system, brain, and bone diseases. People who cook often with aluminum foil (and aluminum pots and pans) risk more exposure than normal to the metal. So, although some aluminum in the diet is inevitable, keep exposure minimal with simple changes such as switching to parchment paper over foil when roasting.
Parchment paper can tolerate temperatures up to 420°F. But note: don’t confuse parchment paper with waxed paper, which can’t withstand high temperatures and will smoke in the oven.
Tip: When roasting, choose oils with higher smoke points (such as canola, sunflower, safflower, grapeseed, and refined coconut oil) to avoid an “off” flavor.
About our expert
Health-food junkie Dawn Jackson Blatner, RDN, CSSD, LDN, is creator of the weekly e-newsletter Nutrition WOW and author of The Flexitarian Diet.