Experts Warn of Dangers of Cannabis Use for Developing Brains

Rutgers physician shares facts about marijuana risks for teens and young adults under 25.

Published on Feb. 13, 2026

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A Rutgers Health physician is warning about the risks of cannabis use, especially for people under 25 as their brains are still developing. She cites concerns about addiction, mental health issues, intellectual impairment, and poor performance linked to regular cannabis use in young people. The physician also notes that cannabis products today are much more potent than in the past, further increasing the risks.

Why it matters

As more states legalize recreational marijuana, health experts are concerned about the potential impacts on young people whose brains are still maturing. Increased potency of cannabis products and the prevalence of use among teens and young adults raise serious public health concerns that require greater education and awareness.

The details

According to Jill M. Williams, a professor in the Department of Psychiatry and the director of the Division of Addiction Psychiatry at Rutgers Robert Wood Johnson Medical School, regular cannabis use has been linked to the development or worsening of several mental health conditions, including depression, anxiety, suicidal thoughts and psychosis. She notes that starting cannabis use at an early age puts someone at higher risk for addiction, as well as other consequences. The THC potency of cannabis products has also increased dramatically, from around 4% in the 1990s to 25% or higher today, further elevating the risks. Edibles and vaping can deliver even higher THC concentrations up to 80-90%.

  • Cannabis was legalized for recreational use in New York and New Jersey 5 years ago.

The players

Jill M. Williams

A professor in the Department of Psychiatry and the director of the Division of Addiction Psychiatry at Rutgers Robert Wood Johnson Medical School.

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What they’re saying

“Since the brain is not fully developed until about the age of 25, there is concern about how cannabis, as well as any other substance, can affect these processes of brain maturation.”

— Jill M. Williams, Professor, Department of Psychiatry and Director, Division of Addiction Psychiatry, Rutgers Robert Wood Johnson Medical School (Mirage News)

The takeaway

As cannabis use becomes more widespread, especially among young people, greater education and awareness is needed about the potential risks to developing brains. Health experts caution that the increased potency of today's cannabis products can lead to addiction, mental health issues, and impaired cognitive function, underscoring the importance of responsible use and policies that prioritize public health.