Sunday marked the high holiday of the stoner year – 4/20. And while the tide may be turning toward marijuana legalization, even casual pot users need to be aware that the drug can take a toll on their minds.

Before pot-smokers and supporters roll their eyes, here’s something to consider: Harvard researchers found abnormalities in areas of the brain that affect emotion, motivation and decision-making for college-aged adults who smoked marijuana casually, according to a study published April 15 in The Journal of Neuroscience.

The study defines casual smoking as lighting up fewer than four times a week on average. That seems right in the ballpark for plenty of GW students, which is why this new information should give even the most ardent legalization supporters pause.

While we may not know everything about how smoking affects the brain, there is certainly evidence to prove that it does in some way, and that can’t be taken lightly. Especially as our knowledge of marijuana develops, it’s up to those who choose to smoke to be mindful of these side effects.

We’re already in the midst of the the march toward legalization, with Colorado and Washington legalizing pot in 2012 and the D.C. Council voting in March to decriminalize small amounts of the drug.

Americans are realizing much of what they thought about pot for decades is false. For instance, it’s impossible to physically be addicted to it the way you can be with other, harder drugs. An analysis by American Scientist concluded that it was as addictive as caffeine.

But this changing attitude should not prevent a serious discussion about the way marijuana may affect our minds. Pot has been too strongly demonized for decades, but as far-reaching legalization draws nearer, let’s get our facts straight.

With legalization, rates of pot consumption will likely increase. As with any other substance, we should continuously seek to learn as much as we can about its effects on our bodies.

“It took us 40 years to convince people that smoking cigarettes was bad for them and by then, people had all these negative effects,” Dr. Jodi Gilman, the author of the Harvard study, told PolicyMic. “I don’t want it to take 40 years to figure out the effects of marijuana.”

It’s almost uncool, especially at a liberal school, to mention pot’s negative side effects. Those voices get lost in the tide of pro-marijuana support. But in the end, marijuana is a psychoactive drug, just like alcohol, caffeine and nicotine.

The difference is that these drugs are legal, and are surrounded by an expansive body of near-conclusive research. We’re fairly confident about the extent of their effects. Studies about marijuana use are still being released frequently, often with conflicting results.

It’s hard to know what information we’ll have about pot the next time 4/20 rolls around, or how many more states will have legalized the drug. That makes it especially important for casual users to stay up-to-date with what they’re putting in their bodies, and adjust their smoking habits accordingly.

Claude Khalife, a freshman majoring in international affairs, is a Hatchet opinions writer.