The fat difference
Grilling cooks food on a raised surface, so rendered fat drips down and away instead of pooling around the food the way it does in a frying pan. For fattier cuts of meat, that alone can meaningfully lower the fat left on the plate. Pan-frying, especially in oil or butter, adds fat rather than removing it. The difference is most pronounced with naturally fatty cuts like sausage or a marbled steak, where a significant portion of the rendered fat simply drips through the grate rather than staying on the plate.
The char tradeoff
High, direct heat creates its own issue: charring and blackened grill marks contain compounds (heterocyclic amines and polycyclic aromatic hydrocarbons) that research has linked to health concerns when eaten often and in quantity. This is mainly a concern with very high heat and visibly burnt spots, not a light sear, and the risk scales with how often and how charred, not with a single cookout.
What the smoke adds
Part of where these compounds come from is fat dripping onto the heat source and producing smoke that then rises back up and coats the food, which is a mechanism specific to open-flame grilling that pan-frying doesn't share in the same way. Using a drip pan, or grilling over indirect heat rather than directly above the flame, reduces how much of that smoke actually reaches the food, which is a more targeted fix than simply lowering the temperature across the board.
A reasonable middle ground
Trimming visible fat before grilling, keeping the heat moderate rather than scorching, and cutting off any heavily blackened bits after cooking address most of the downside without giving up the technique. Marinating beforehand also appears to reduce char-compound formation somewhat, giving you two easy levers instead of one. Flipping food more frequently helps too, since it spends less continuous time against the hottest part of the grate. Between the two methods, grilled lean protein with the char kept in check is generally the better everyday choice over regularly pan-frying in added oil.
What about a grill pan indoors?
A ridged grill pan used on a stovetop gets some of the same fat-drainage benefit as an outdoor grill, since rendered fat pools in the channels between the ridges rather than surrounding the food. It doesn't produce the same smoke exposure an open flame does, which arguably makes it the lower-char-compound option of the two, even though it lacks the same flavor most people associate with outdoor grilling. For someone without regular access to an outdoor grill, it's a reasonable middle path between grilling and standard pan-frying.
Gas versus charcoal
Charcoal grilling generally produces more smoke and a higher likelihood of char-compound formation than gas grilling, since charcoal burns less evenly and tends to run hotter in unpredictable spots. This doesn't mean charcoal needs to be avoided, but it does mean the moderate-heat, drip-pan, and trim-the-char habits described above matter somewhat more with charcoal than with a gas grill, where temperature is easier to control precisely and keep at a steadier, moderate level throughout the cook.
Processed meats add a separate concern
Hot dogs, sausage, and other processed meats carry their own separate health considerations tied to sodium and preservation methods, independent of whatever cooking method is used on them. Grilling a hot dog doesn't remove the concerns already baked into the product before it hit the grill, which is worth remembering since grilled food in general has a healthier reputation that doesn't automatically transfer to every item that happens to go on the grate. The fat-and-char considerations discussed above apply most clearly to whole cuts of meat, fish, and poultry — a genuinely different category from a processed product that starts out with its own separate list of considerations.
Fish and vegetables on the grill
Fish and vegetables tend to spend less time over direct heat than a thick cut of meat, which naturally limits how much char-compound-forming exposure they get compared to a well-done steak left on the grate for a long stretch. Grilled vegetables in particular are a genuinely strong choice from a health standpoint, since they pick up the same smoky flavor without the fat-dripping mechanism that produces the smoke exposure linked to those compounds in meat. Rounding out a mixed grill with more vegetables and fish, and less meat cooked to a heavily charred finish, shifts the whole plate toward the more favorable end of this tradeoff without giving up the format entirely.
A foil packet or a fish basket also helps here, since it shields more delicate fish from the direct flame while still picking up some grilled flavor from the heat and smoke around it, and it makes a genuinely delicate fillet far less likely to fall apart or stick to the grate partway through cooking.
