I got very good at making oatmeal over the course of the month. Kathleen Elkins/Business Insider For the month of January, I took the "Elon Musk Challenge" and ate on $2 a day.

I was skeptical heading into the experiment. It sounded dreadful — and impossible — but surprisingly, a $2-a-day food budget is more than possible.

Perhaps even more surprising was what I found to be the hardest part of the challenge. It wasn't coping with hunger pains or sacrificing chocolate, one of the many luxury items that I take for granted. It wasn't even the monotony of eating the same nine foods day after day.

The hardest, most uncomfortable part of the month was accepting free food from other people.

The Elon Musk challenge, as I interpreted it, is about utilizing your resources and problem solving in order to make $2-a-day work. For that reason, I figured food offered to me would be fair game, hence a rule that I established prior to starting: I can accept food from other people or any freebies.

While I was never actively seeking free meals, some very generous friends concerned about my protein and caloric intake helped out along the way, offering snacks and treating me to the occasional meal over the course of the month. Plus, what were they going to do when I showed up to hang out at a restaurant or bar, only to order a free cup of water because I couldn't afford anything on the menu?

Sure, I could have avoided going out to restaurants or bars all together, but if you want to interact and socialize with your friends, it often means eating and drinking with them.

My friends were nice enough to include me in the fun, buying me something or sharing whatever they had ordered, but it's strange being completely reliant on others for money. It's straight up awkward when the check comes and you can't contribute.

I was treated to this fluffy omelet, bowl of hearty oats, and giant cup of ice cream over the course of the month. Kathleen Elkins/Business Insider

Don't get me wrong, it was more than exciting to dig into a fluffy omelet or topping-heavy bowl of ice cream for a change — and I couldn't have been more appreciative of my friends — but it didn't quite feel right. While hard to pinpoint the exact emotion, it's a combination of guilt, embarrassment, and hopelessness.

It's highly uncomfortable having people pay for you.

As thrilling as those supplemental meals were, I'm not sure if they were worth the discomfort that was part of the package.