The Real Reason You're Not Allowed To Bring Cheesecake On An Airplane

The family is demanding you fly in with your world-famous cheesecake for the summer reunion. Guess what. You're off the hook. Cheesecake on a plane is a hard no — at least in your carry-on, but really, who's going to pack cheesecake in checked luggage? And cheesecake isn't the only unexpected food item on TSA's no-fly list. In fact, the Transportation Security Administration's Liquids Rule (aka 3-1-1 Rule) applies to more foods than you may think. And it's in no way arbitrary.

Established in 2006, the TSA's 3-1-1 Rule stems from the attempted bombing of airlines operating between the U.S. and the U.K. According to The New York Times, in August 2006 British investigators intercepted a group of terrorists who planned to board planes with hand luggage containing explosive liquids, basically smuggling the makings of a bomb onto the aircraft in plain sight. In the immediate aftermath of the thwarted bombing attempts, the U.S. banned all liquids, gels, and lotions (except prescribed medicine and children's beverages) from carry-on luggage.

After extensive testing, the 3-1-1 Rule as we know it today emerged as a loosening of restrictions to accommodate the flying public (via USA Today). It may seem restrictive, but it's a far cry from the original emergency protocol — even with its inclusion of banned or limited liquid and liquid-adjacent foods.

I'm good with the toiletries part. I have the 3-1-1 Rule down pat. But cheesecake? Really?

We hear you. It seems a little bit of a reach, but the rigorous testing that led to the 3-1-1 Rule — the calculations that determined, yes, we can travel with our favorite moisturizer or cologne in our hand luggage (especially good news for die-hard carry-on-only travelers) — is designed to proactively address all potential workarounds. While cheesecake isn't specifically named on the TSA's banned-items list, it's apparently liquid-adjacent enough that it could be of interest to individuals with malicious intent (via AirHelp).

Some would argue cheesecake falls under the TSA's rule for creamed and soft cheeses which stipulates a carry-on allowance of 3.4 ounces. Other foods on the list include gravy, hummus, jams, jellies, and peanut butter. But unlike gravy or peanut butter, cheesecake (or any creamy cheese for that matter) is tough to measure by liquid volume. For reference Cool Conversions estimates one ounce of cream cheese equals approximately 1.1 U.S. fluid ounce.

And then there's the question of squeezing that 3.4-liquid-ounce serving of cheesecake into a container you can fit into your quart-size toiletries bag. Sure, you might be able to convince a sympathetic TSA agent you're hand delivering your signature cheesecake at the request of your beloved great-grandmother, but is it worth the effort? Better to err on the side of caution and make the cake when you reach your destination.