For LGBTQ+ teens, what parents think mattered — but only for the use they hadn't planned
We asked 82 LGBTQ+ teens every morning what they planned to use that day. Parental disapproval shaped the days they hadn't planned on—and made no difference to the days they had.
Nearly everyone who studies teen substance use asks about peer influence and parental disapproval. Less is known about when those influences actually operate. This study points to an answer: they show up most in the moments a young person hadn't already decided.
Eighty-two lesbian, gay, bisexual, queer, and pansexual teens aged 15 to 19 who were regularly vaping or smoking answered questions on their phones every morning for a month. Each morning they reported what they'd used the day before and what, if anything, they planned to use that day. Before the month started, we asked how many of their friends used, and how wrong they thought their friends and parents would find it.
Plans mattered enormously. On days a teen woke up intending to use nicotine, cannabis, or alcohol, they were far more likely to do so — nine or ten times the odds, consistently across all three.
But the social influences worked differently depending on whether use was planned.
Teens who believed their parents strongly disapproved of nicotine were much less likely to use it on days they hadn't planned to. Among those who saw their parents as permissive, unplanned nicotine use was near-certain; among those who saw parents as strongly disapproving, it dropped to about one day in five. On planned days, what parents thought made no difference at all.
Friends worked the other way, and specifically LGBTQ+ friends. The more sexual minority friends a teen believed used nicotine, the more likely they were to use on days they hadn't planned to — rising from about 15 percent to about 55 percent as that number went from one friend to nine. Beliefs about heterosexual friends showed no such effect. For alcohol, friends' use predicted planned drinking rather than unplanned.
Two things we expected and didn't find: seeing nicotine posts on social media wasn't related to daily use, and beliefs about what LGBTQ+ friends thought of using weren't either — largely because almost everyone in the sample described their LGBTQ+ friends as approving, leaving too little variation to detect anything.
Why it matters
Unplanned use is where these influences live. That's an argument for interventions that arrive in the moment—refusal skills, correcting inflated estimates of how much friends actually use—rather than only in a weekly session. It's also a reason to involve parents, whose disapproval appears to do real work even with teens who may not be out to them, or who assume it wouldn't matter.
What this doesn't tell us
Eighty-two teens, most of them White and cisgender, all of whom were already using nicotine regularly and had experienced recent anti-LGBTQ+ stress. The findings may not extend to LGBTQ+ young people who use less, or to a more racially diverse group. We measured beliefs about friends and parents once, at the start, so we can't see how they shifted. And this is observational: we can say that teens who perceived stronger parental disapproval used less unplanned nicotine, not that changing a parent's stance would change a teen's behavior.
Mereish EH, Parnes JE, Rentería R, Miranda R Jr. Planned versus unplanned daily substance use among sexual minority youth: the moderating role of social norms. Clinical Psychological Science, 2025.
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Cannabis lifted mood most when young people felt worst—or best
Youth often say cannabis helps them feel better. Tracking 85 young people five times a day showed the lift was biggest at their emotional extremes—and smallest when they felt ordinary.
Young people commonly say they use cannabis to feel better, or to stop feeling bad. Both are true, it turns out, but not evenly. What cannabis did to mood depended almost entirely on how a young person was feeling right before they used.
Eighty-five people aged 15 to 24 who were using cannabis at least twice a week and wanted to cut back carried a handheld device for about a week. It prompted them roughly five times a day to rate how they were feeling, and they also reported just before and just after each time they used. This was before any treatment started, so we were watching ordinary life, not a response to therapy.
Cannabis use was followed by a rise in good feelings—energized, happy, sociable, relaxed—and a drop in bad ones. But the size of the mood lift traced a U-shape. It was largest when someone had felt unusually low for them, and also largest when they had felt unusually good. When mood was around a person's ordinary baseline, using barely moved it.
The pattern for bad feelings depended on how severe someone's cannabis problems were. Among those with more symptoms of cannabis use disorder, using was followed by a drop in negative feelings whether they had felt unusually bad or unusually calm beforehand. Among those with fewer symptoms, cannabis only relieved negative feelings when they were already elevated.
Why it matters
The standard account is that people start using for pleasure and later use mainly to escape discomfort. That's not what we found. The pleasure effect stayed just as strong across the whole range of severity — the relief effect got added on top of it. That's a different picture of how a cannabis problem takes hold, and it suggests treatment has to address both, not assume one has replaced the other.
It also points somewhere clinically useful: the moments when a teen is feeling flat, not just the moments they're distressed, may be when cannabis is most reinforcing.
What this doesn't tell us
Eighty-five people, about a week of data each, and no experiment—we observed what people reported, so we can't say cannabis caused the mood changes, only that they followed use. Everyone here was already trying to cut back, and anyone with a co-occurring psychiatric diagnosis was excluded, which leaves out many young people we see clinically. Participants recorded their own use without any verification, and we didn't know the potency of what they used. Some of the mood swings we measured may simply be ordinary teenage variability rather than anything to do with cannabis.
Emery NN, Carpenter RW, Acuff S., Meisel SN, DeFalco A, Soyster PD, Miranda R. Jr. The effect of cannabis use on the time course of positive and negative affect in the daily life of youth. Psychopharmacology, 2026
Cutting back on cannabis was linked to more trouble sleeping—but only in the first two weeks
Young people often say cannabis helps them sleep. We followed 65 teens and young adults every morning for six weeks to see what actually happened when they cut back—and found the hardest stretch comes early.
Young people often say cannabis helps them sleep, and that stopping makes sleeping harder. If that's true, sleep could be one reason treatment is hard to stick with. We wanted to see what actually happened, day by day, while young people were trying to cut back.
Sixty-five people aged 15 to 24 who wanted help reducing their cannabis use answered questions on a handheld device every morning for six weeks while receiving counseling. Each morning they reported how much cannabis they'd used the day before, how long they'd slept, and how much trouble they'd had sleeping.
Two things stood out. Early in treatment—roughly the first two weeks—participants reported less trouble sleeping on days they used more cannabis than their own usual amount, about 14 percent less per additional gram. The flip side is that cutting back was linked to more difficulty sleeping, right at the point when people were working hardest to change. That effect faded: after about day 13, how much someone used stopped predicting their sleep either way, and reported sleep trouble declined steadily across the six weeks.
Second, simply skipping cannabis on a given day wasn't linked to sleep at all—not to how long people slept, not to trouble sleeping. Participants used on about 60 percent of days and rarely went more than a day or two without, so most may not have gone long enough without cannabis for withdrawal-related sleep problems to appear.
One unexpected result: drinking alcohol was tied to shorter sleep across much of the study, more consistently than cannabis was.
What this means in practice
the first two weeks look like the moment to talk with young people about sleep — what to expect, and skills to manage it — rather than waiting for it to come up.
What this doesn't tell us
This is a small study, and everyone in it was already seeking treatment—we can't say whether the same pattern holds for young people who aren't. The data were collected between 2009 and 2012, and both cannabis products and how young people use them have changed considerably since. And because this looks at what people reported day to day rather than testing a sleep treatment, it can't tell us whether helping someone sleep better would reduce their cannabis use.
Parnes JE, LeCavalier KNS, Meisel SN, Miranda R. Dynamic associations between cannabis use and sleep in adolescents and young adults during a cannabis intervention trial. Journal of Research on Adolescence, 2025.