news World NewsNewsLegalization Using alcohol and bud simultaneously not associated with engaging in certain risky activities: study Another study found that those who combine substances were more likely to drink heavier and more often compared to those who drank only alcohol. Author of the article:Angela Stelmakowich There were differences in SAM days for those younger than 21 and those 21 and older. / PHOTO BY WILDPIXEL / ISTOCK / GETTY IMAGES PLUS