Month: February 2022

A forest fire in northern California and a mile-long glacier breaking apart appear in your news feed. The stark reminders of climate change are constant, and may cause additional stress to your daily tasks. For example, in surveying your shopping cart filled with wipes, sandwich bags, and packets of baby food, you may question your choices, knowing that the plastic in those items will never break down completely. You may feel guilty about driving the short distance to the store, or you may struggle to stop worrying about how your actions will affect future generations.

What is climate anxiety?

Climate anxiety, or eco-anxiety, is distress related to worries about the effects of climate change. It is not a mental illness. Rather, it is anxiety rooted in uncertainty about the future and alerting us to the dangers of a changing climate. Climate change is a real threat, and therefore it's normal to experience worry and fear about the consequences. Anxiety about the climate is often accompanied by feelings of grief, anger, guilt, and shame, which in turn can affect mood, behavior, and thinking.

How common is climate anxiety?

According to a survey by the American Psychological Association, more than two-thirds of Americans experience some climate anxiety. A study published by The Lancet found that 84% of children and young adults ages 16 to 25 are at least moderately worried about climate change, and 59% are very or extremely worried. This makes sense, as children and young adults will disproportionately suffer the consequences of environmental changes. A 2021 UNICEF report estimates that one billion children will be at "extremely high risk" as a result of climate change. Children and young adults are also particularly vulnerable to the effects of chronic stress, and climate anxiety may affect their risk of developing depression, anxiety, and substance use disorders.

How does climate change affect mental health?

In addition to existential worries and fears about the future, climate change can affect mental health directly (such as through natural disasters or heat) and indirectly (through displacement, migration, and food insecurity). Rising temperatures have been associated with increases in emergency department visits for psychiatric reasons, and may impair cognitive development in children and adolescents. Furthermore, food insecurity is associated with depression, anxiety, and behavioral problems.

How can you manage climate anxiety?

As uncertainty and a loss of control characterize climate anxiety, the best treatment is to take action. On an individual level, it’s therapeutic to share your worries and fears with trusted friends, a therapist, or by joining a support group. You can also make changes to your lifestyle consistent with your values. This may include deciding to take fewer flights, joining a protest, or increasing public awareness about climate change through advocacy. Joining an organization like The Good Grief Network can help you process feelings related to climate anxiety and connect with others to take meaningful action.

How can you help a younger person?

Climate anxiety disproportionately affects children and youth. To be an ally for a child, adolescent, or younger adult with climate anxiety, you can consider showing your support in the following ways:

• Validate their concerns. “I hear you, and it makes sense that you are worried (or angry) about this issue.”
• Help direct their efforts to advocacy groups. Spend time together researching organizations that they can get involved with.
• Educate yourselves on steps you both can take to minimize your impact on the environment.
• Support your loved one’s decisions to make changes to their lifestyle, especially changes they can witness at home.
• Spend time in nature with your family, or consider planting flowers or trees.

The bottom line

Climate anxiety is rife with uncertainty, but taking action may help you feel in control. Talk with others, join forces, and make lifestyle changes based on your values.

About the Author

Stephanie Collier, MD, MPH, Contributor

Dr. Stephanie Collier is the director of education in the division of geriatric psychiatry at McLean Hospital; consulting psychiatrist for the population health management team at Newton-Wellesley Hospital; and instructor in psychiatry at Harvard Medical School. … See Full Bio View all posts by Stephanie Collier, MD, MPH

As of June 2022, 37 US states have passed medical cannabis laws and 19 states have legalized recreational cannabis. Cannabis has proven beneficial for a range of conditions such as childhood seizure disorders, nausea, vomiting, and loss of appetite in people with HIV/AIDs.

In the meantime, a new generation of cannabis products has exploded onto the scene, driven by marketing that fuels a multibillion-dollar industry. The average content of THC (tetra-9-tetrahydrocannabinol, the psychoactive and potentially addictive chemical in cannabis) in smoked whole-plant products has risen from 1% to 4% in the 1970s to 15% to 30% from today’s cannabis dispensaries. Edibles and vapes may contain even higher concentrations of THC.

While public perception that cannabis is a harmless substance is growing, the long-term benefits and risks of cannabis use remain unclear. However, one consistent pattern of research has emerged: heavy long-term cannabis use can impact midlife cognition.

New research on cannabis use and cognition in midlife

Recent research published in The American Journal of Psychiatry closely followed nearly 1,000 individuals in New Zealand from age 3 to age 45 to understand the impact of cannabis use on brain function. The research team discovered that individuals who used cannabis long-term (for several years or more) and heavily (at least weekly, though a majority in their study used more than four times a week) exhibited impairments across several domains of cognition.

Long-term cannabis users’ IQs declined by 5.5 points on average from childhood, and there were deficits in learning and processing speed compared to people that did not use cannabis. The more frequently an individual used cannabis, the greater the resulting cognitive impairment, suggesting a potential causative link.

The study also found that people who knew these long-term cannabis users well observed that they had developed memory and attention problems. The above findings persisted even when the study authors controlled for factors such as dependence on other drugs, childhood socioeconomic status, or baseline childhood intelligence.

The impact of cannabis on cognitive impairment was greater than that of alcohol or tobacco use. Long-term cannabis users also had smaller hippocampi (the region of the brain responsible for learning and memory). Interestingly, individuals who used cannabis less than once a week with no history of developing dependence did not have cannabis-related cognitive deficits. This suggests there is a range of recreational use that may not lead to long-term cognitive issues.

More studies are needed on cannabis use and brain health

The new research is just one of several studies suggesting there is a link between long-term heavy cannabis use and cognition. Still, future studies are needed to establish causation and explore how long-term cannabis use might impact the risk of developing dementia, since midlife cognitive impairment is associated with higher rates of dementia.

What should you do if you experience cognitive effects of cannabis?

Some people who consume cannabis long-term may develop brain fog, lowered motivation, difficulty with learning, or difficulty with attention. Symptoms are typically reversible, though using products with higher THC content may increase risk of developing cognitive symptoms.

Consider the following if you are experiencing cannabis-related cognitive symptoms:

• Try a slow taper. Gradually decrease the potency (THC content) of cannabis you use or how frequently you use it over several weeks, especially if you have a history of cannabis withdrawal.
• Work with your doctor. Be open with your doctor about your cognitive symptoms, as other medical or psychiatric factors may be at play. Your doctor can also help you navigate a cannabis taper safely, and potentially more comfortably, using other supportive means. Unfortunately, most patients are not comfortable talking with their doctors about cannabis use.
• Give it time. It may take up to a month before you experience improvements after reducing your dose, as cannabis can remain in the body for two to four weeks.
• Try objective cognitive tracking. Using an app or objective test such as the mini-mental status exam to track your brain function may be more accurate than self-observation. Your mental health provider may be able to assist with administering intermittent cognitive assessments.
• Consider alternative strategies. Brain function is not static, like eye color or the number of toes on our feet. Aerobic exercise and engaging in mindfulness, meditation, and psychotherapy may improve long-term cognition.

Cannabis is an exciting yet controversial topic that has drawn both hype and skepticism. It is important for individuals and healthcare professionals to place emphasis on research studies and not on speculation or personal stories. Emerging studies suggesting the connection between long-term heavy use of cannabis and neurocognition should raise concern for policymakers, providers, and patients.

About the Authors

Kevin Hill, MD, MHS, Contributor

Dr. Kevin Hill is director of addiction psychiatry at Beth Israel Deaconess Medical Center, and an associate professor of psychiatry at Harvard Medical School. He earned a master’s in health science at the Robert Wood Johnson … See Full Bio View all posts by Kevin Hill, MD, MHS

Michael Hsu, MD, Guest Contributor

Dr. Michael Hsu is a resident psychiatrist and is currently the chief resident of outpatient psychiatry at Brigham and Women's Hospital, a teaching hospital of Harvard Medical School. After graduating from the University of Pennsylvania with … See Full Bio View all posts by Michael Hsu, MD