You need one of those small insulated lunch bags and a blue ice pack. It’ll keep it cold.
This subject has come up before, and I think the general consensus was that making ‘gotcha’ brownies with massive amounts of laxative could be considered assault, but just making something that you would conceivably eat yourself was okay. I would try tuna or chicken salad with lots of tabasco or hot peppers mixed in.
Stealing lunches is never okay.
It may be of some interest for you to know that sugar free candy with the ingredients sorbitol, maltitol, or xylitol can cause truly spectacular flatulance and uncontrollable diarrhea if eaten in large doses (say, 10-12 pieces). When I use the words “spectacular” and “uncontrollable”, I may be understating it a bit. Also helpful to point out that many popular candies (such as Reese’s cups) are exact replicas of their sugar free counterparts.
I had a diabetic friend who spent a long, sad evening in the bathroom because of this. There is nothing like killing all of one’s household plants and crapping the bed to give a person a sense of remorse and desire to live a more honest life. You will be doing him a favor.
Also works on annoying bosses, especially before a big meeting.
I am hesitant to ask for an explanation.
I don’t understand all these people going “Is it possible that this person just really needs the food?” Come on! Like others mentioned, this person in his workplace is working and therefore earning money and should be able to buy their own foods to bring in as lunch. You can get a cheap loaf of bread for less than a dollar and some cheap lunch meat or peanut butter and bam, lunch. If a person is that hard up for money that they’re willing to steal the food of others, they either need to prioritize their budget or at least have the gall to ask a person for some of their lunch and not steal it. Stealing somebody else’s lunch is like stealing the energy they need for that time period and the money they spent to make that lunch (even if it isn’t much) and just makes you a dick.
“Spectacular” and “toxic”.
A good dollop of Dave’s Insanity Sauce or Scorned Woman should do the trick very nicely. 
BTW I presume that once you’ve caught the thief, if he or she reports to you, you’ll be firing them, right? 
I say put mealworms in your sandwhich. That would probably disgust most lunch thieves.
My thoughts exactly. I work in a supermarket. & recently lunches have gone missing. I’d rather go hungry than steal from my workmates - most of who are on minimum wage. (the managers & office staff have a separate lunchroom)Plus there is usually bread, margarine, tomato sauce & sometimes breakfast cereal provided. If the bakery overcooks their cakes they will be there too. Sometimes date expired but still safe other food as well.So if the person stolen from doesn’t want that food they have to spend their timed lunch buying more food & getting it “stickered” by a supervisor to show its been paid for. There were already cameras in the lunchroom, but now they are getting one trained on the fridge.
Good Lord.
When this happened while I was in elementary school, my mom left a nasty note in my lunchbox, and the thieves actually took the note to the principal and complained. And thus my lunch was never again stolen!
So, any idea if your coworkers are as idiotic as my classmates?
I would bet that the thefts have nothing to do with food (and the stolen lunches are doubtlessly thrown away, not eaten) but instead someones warped urge to dominate and abuse a coworker…
As you and others have stated, these people are employed, and food is inexpensive, no one working would have to resort to theft to keep from going hungry.
That said, if the OP could find the thief, it would be kosher in my book to pay his (the thiefs) parked car a little visit during a work break, to check it for fresh key scratches.
I’ve never seen anything like my work place - even at other supermarkets. Every checkout has a camera trained on it. & there are cameras everywhere else too - with the exception of the toilets & locker rooms.
A potted meat sandwich should fix this person.
The last time someone stole a sandwich from my lunch they ruined the other ones in the bag. I had like 4 sandwiches in the bag for my lunches that week. The person that stole food regularly in the place had plenty of money to buy their own food, they just didn’t care that the food was somebody else’s if they wanted it. They also ate food directly from on the table and didn’t clean their greasy food remains off the table. They were worse than a pig.
Make the catfood/pepper sandwich and see if it stops. If it doesn’t invest in an insulated lunch bag and keep your lunch in your desk.
No, only if you go through with it. There’s no harm in merely thinking about it.
Do not do this. This is illegal. This is unethical. This is disproportionate to the theft. And many workplaces have cameras covering the parking lot.
Yes. Intentional infliction of nervous shock.
Insurace does not cover intentional injury to another person.
Now, now. You’re crimping the style of the Masters of the Dysproportionate Response.
Cat food? Sure! (I saw District 9, after all!) Besides, US cats often eat better than 4th world citizens.
Hot sauce? Yah, you betcha! I love the burn. My normal lunch is toxic to many.
Property damage or bodily harm? Not so much.
Who said anything about injury? Eating cat food never hurt anyone. (Viktor Belenko, the Soviet defector, says it tastes pretty good).
Laws vary by jurisdiction blah blah this is not legal advice but usually (usually) for an Intentional Infliction of Emotional Distress claim, usually (usually) the plaintiff must experience “extreme emotional distress” and the defendant’s conduct must be “extreme and outrageous.”