Study: Marijuana legalization ➡️ increased consumption

Adults in states where weed is legal use it 24% more than in states where it's illegal.

Why it matters: While it seems obvious, a new study presents strong evidence that legalization causes increased use at a time when marijuana consumption is rising across the country.

• Researchers at the University of Minnesota and the University of Colorado studied marijuana use by more than 3,400 adult twins — ideal subjects who tend to share genes, socioeconomic status and parental influences.

State of play: Michigan is one of 19 states where marijuana is legal for recreational use; 37 states have legalized medicinal use.

• Recorded marijuana use nationwide is at an all-time high among adults aged 19-30, with 43% using in the past year and 29% in the last month.

Yes, but: All that weed use might not be a bad thing.

• Study co-author John Hewitt said in a statement that increased use, "may be associated with less alcohol-related problems, and otherwise does not, in general, seem to have adverse consequences."