Smartphones, social media, and adolescent health outcomes

The negative health consequences of social media use in adolescents and young adults are increasingly being recognized. In a previous American Family Physician Blog post on screen time use in children, Dr. Lilian White mentioned a correlation between greater social media use and reduced life satisfaction in adolescents. A 2017 Curbside Consultation discussed the relationship between social media use and mood disorders, fueled by the fear of missing out (FOMO), and reviewed resources and tools for unplugging or limiting time spent on social media.

Recently, a prospective cohort study in JAMA Network Open used objective data from a “digital phenotyping” app to evaluate the effects of a 1-week social media detox intervention on mental health. 373 U.S. young adults aged 18 to 24 years with smartphones completed a 2-week baseline assessment of their use of Facebook, Instagram, Snapchat, Tik Tok, and X. The optional intervention decreased 295 participants’ daily social media screen time from 1.9 to 0.5 hours. These changes were associated with statistically significant reduced symptoms of anxiety by 16.1%, depression by 24.8%, and insomnia by 14.5%.

Adolescents access social media platforms through smartphone apps. Another recent study examined associations of various health outcomes with smartphone ownership in a sample of more than 10,000 participants in the Adolescent Brain Cognitive Development Study. At age 12 years, 64 percent of children owned a smartphone. Compared to those without a smartphone, smartphone owners had higher risks for depression (odds ratio=1.31), obesity (OR=1.40), and insufficient sleep (OR=1.62). Risks of obesity and insufficient sleep increased with earlier age at smartphone acquisition, and the 1546 children who acquired a smartphone between the ages of 12 and 13 had worse mental health and sleep outcomes than the 1940 children who remained without smartphones at age 13.

Restricting use during school hours does not appear to affect overall smartphone or social media use or mental health. A cross-sectional study in the United Kingdom compared students at 20 secondary schools with restrictive phone policies (recreational use not permitted) with those at 10 schools with policies permitting recreational phone use. 1227 students age 12 to 15 years participated in the study, which assessed mental wellbeing using the Warwick-Edinburgh Mental Well-Being Scale. Students who attended schools with restrictive policies compensated for lower phone use during school hours by using their phones and accessing social media more after school and on weekends. Not surprisingly, there were no differences in mental well-being between the groups.

On December 10, Australia implemented the world’s first ban on social media accounts for children younger than age 16. Instagram, Facebook, Threads, Snapchat, YouTube, TikTok, Kick, Reddit, Twitch and X were all required to deactivate existing accounts for younger children and use age verification software for new accounts to avoid millions of dollars in fines. The potential health benefits of this policy remain to be seen.

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This post first appeared on the AFP Community Blog.

Shared decision making for colorectal cancer screening tests

Most of the major cancer types have a single recommended screening test. For breast cancer, mammography. For cervical cancer, cytology and/or human papillomavirus testing. For lung cancer, low-dose computed tomography (CT). Colorectal cancer is unique in that physicians and patients have a menu of acceptable screening options, ranging from various stool-based tests to CT colonography, colonoscopy, and most recently, a blood test for circulating tumor DNA.

Guidelines recommend shared decision making with average-risk adults aged 45 to 75 years to select a colorectal cancer screening strategy that aligns with patients’ preferences and values. A recent scoping review of 28 studies in the United States and Canada explored factors that play important roles in these conversations. Researchers identified 4 domains that influence patients’ decision making: test attributes (accuracy, cost, convenience, and complications); recommendations from their personal physician; fear, discomfort and embarrassment for some regarding colonoscopy and stool tests; and external factors (culture, family input, socioeconomic status, and transportation access).

The U.S. Preventive Services Task Force assigned a “C” grade (offer selectively, individualized decision) to colorectal cancer screening in adults aged 76 to 85 years due to a small net benefit of screening in this age group. A cluster randomized trial in older adults evaluated the effect of physician training in shared decision-making on receipt of patient-preferred colorectal cancer screening (which could include no testing) and on overall screening rates. At 12 months, about half of patients in each group had received their preferred approach, with no significant difference between the groups in test uptake.

A pitfall for clinicians is limiting patients’ test options to colonoscopy due to a belief that it is the “gold standard” test, even though no data have demonstrated clear superiority over fecal immunochemical tests. An editorial in the September 2025 issue of American Family Physician discussed optimizing the role of noninvasive colorectal cancer screening tests, and an editorial in the October 2025 issue reflected on downsides of colonoscopy as a primary screening strategy. For patients who choose to undergo colonoscopy, adherence to evidence-based surveillance guidelines is critical to preventing harms associated with repeating colonoscopy at inappropriately short intervals.

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This post first appeared on the AFP Community Blog.

My favorite public health and health care books of 2025

This year's best of list includes only three titles that were actually published in 2025. Six books were written by doctors, and two provide complementary perspectives on the infamous Andrew Wakefield and the epidemics of vaccine-preventable diseases resulting from falsified research and shameless self-promotion of a thoroughly debunked theory. As always, books are listed alphabetically by title. For more favorite reads, feel free to browse my lists from 2024, 2023, 2022, 2021, and previous years.

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1. Booster Shots: The Urgent Lessons of Measles and the Uncertain Future of Children’s Health, by Adam Ratner

2. The Doctor Who Fooled the World: Andrew Wakefield’s War on Vaccines, by Brian Deer

3. Dopamine Nation: Finding Balance in an Age of Indulgence, by Anna Lembke

4. Dr. Mutter’s Marvels: A True Tale of Intrigue and Innovation at the Dawn of Modern Medicine, by Cristin O’Keefe Aptowicz

5. Facing the Unseen: The Struggle to Center Mental Health in Medicine, by Damon Tweedy

6. Gettysburg Surgeons: Facing A Common Enemy in the Civil War’s Deadliest Battle, by Barbara Franco

7. My Father’s Brain: Life in the Shadow of  Alzheimers, by Sandeep Jauhar

8. One by One by One: Making A Small Difference Amid A Billion Problems, by Aaron Berkowitz

9. A Return to Healing: Flexner, Osler, and How American Medicine Went Astray, by Andy Lazris and Alan Roth

10. Slow Cooked: An Unexpected Life in Food Politics, by Marion Nestle

Upcoming article on mental health disorders during the Civil War

 

Update: The full article is now available in the Winter 2025 issue of the Journal of Lancaster General Hospital.

State and federal support for primary care: meaningful but insufficient

For a clear-eyed view of the U.S. health system factors that have collectively conspired to cripple primary care, the five-part New England Journal of Medicine series "The Primary Care Puzzle" by cardiologist and medical reporter Dr. Lisa Rosenbaum is a worthwhile read. Although I would usually frown on a subspecialist writing a pessimistic view of the problems in my field of medicine (family medicine comprising the majority of primary care in Lancaster and elsewhere), Rosenbaum has interviewed all of the key informants and gets most of the story right.

Since it has become clear that primary care is a common good, like law enforcement and public libraries, it's fair to ask what state and federal governments have been doing to support high-quality primary care. A systematic review in JAMA Health Forum discussed 5 federally-supported programs in primary care "transformation" from 2011 to 2021: 4 demonstration projects in paying primary care practices prospectively and EvidenceNOW Advancing Heart Health, which focused on improving cardiovascular outcomes. The numbers of participating practices ranged from 500 to nearly 3000. None of these programs was a failure or an unqualified success (improving health outcomes, the patient and clinician experience, or saving the system money).

The Trump administration has shown little interest in supporting primary care beyond allowing persons to use health savings accounts to pay membership fees to direct primary care practices. This change will help some access primary care, but huge funding cuts to Medicaid and premium subsidies for health insurance marketplace plans will result in millions more losing access to their doctors. (Further damaging to primary care are the hostile takeover and suspension of activities of the Advisory Committee on Immunization Practices and the U.S. Preventive Services Task Force, respectively.)

States have taken different approaches to better resource primary care. Oregon, Delaware, Colorado, and California recently passed legislation aiming to gradually increase the proportion of all health care spending on primary care from 5-7% to 11.5% to 15% over the next decade. Delaware and Rhode Island have combined primary care spending targets with caps on overall health care spending increases.

In September, the Milbank Memorial Fund published a policy menu for states looking to strengthen primary care, organized by 5 priority areas and spotlighting examples of policy actions taken by states that are diverse geographically and ideologically:

1. Make and Keep Primary Care a Top Policy Priority

2. Pay Primary Care More and Differently

3. Make It Easier for People to Access Their Primary Care Clinician

4. Expand and Support and Current and Future Primary Care Workforce

5. Build Provider Capacity to Provide Patient-Centered, Whole-Person Care

These initiatives are a good start, but they are not nearly enough to close the gap between the inadequate primary care workforce we have and the one we need to make the lagging U.S. competitive internationally in health care spending and outcomes.

Hepatitis B vaccine birth dose protects infants against lifelong health consequences

Since 2018, the American Academy of Pediatrics and the Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) have recommended universal hepatitis B vaccination of medically stable newborns weighing at least 2,000 grams within 24 hours of birth. After the unprecedented wholesale dismissal and replacement of the ACIP membership in June 2025, the American Academy of Pediatrics posted a fact sheet on its website emphasizing the significance of the hepatitis B vaccine birth dose and infant series in preventing acquisition of chronic infection. Although the U.S. Preventive Services Task Force recommends screening for hepatitis B virus at the first prenatal visit, a recent study found that more than 1 in 7 pregnant patients are never tested; some women do not receive any prenatal care or become infected later in pregnancy.

Perinatal hepatitis B infection has lifelong health consequences; 90% of infected infants develop chronic hepatitis B, and 15% to 25% of those die from cirrhosis or liver cancer in adulthood. In addition to being vertically transmitted from infected mothers, hepatitis B virus can also be passed on to infants through incidental contact with blood or body fluids of infected household members. The birth dose thus functions as a safety net for thousands of children who, before 1990, were being overlooked by risk factor–based vaccination strategies. Since its implementation in the United States, the birth dose has not only been associated with higher completion rates for the full hepatitis B vaccine series but also higher odds of receiving all recommended vaccines by age 19 months. A study of birth dose use in Washington, DC, found that vaccine refusals declined from 12.1% in 2017 to 4.1% in 2020 and remained below 4% in 2021 and 2022.

Nonetheless, when the reconstituted ACIP met in September 2025, it came close to voting to delay the first dose of hepatitis B vaccine to 1 month of age in infants born to hepatitis B surface antigen-negative mothers. This occurred despite the presentation of a systematic review by CDC staff that found no increased risk of any serious safety outcome when the vaccine was administered within 24 hours of birth. As highlighted in an in-depth analysis of the meeting by former ACIP members, the new committee repeatedly ignored its established processes for evaluating evidence and deliberating recommendations. Family physicians and former ACIP workgroup members Doug Campos-Outcalt and Jonathan Temte observed in a JAMA Viewpoint: “The evidence-based processes used by the ACIP were adopted to prevent exactly what happened at the first 2 meetings this year: presentation of anecdotes, selective quoting of single studies, and a lack of in-depth evaluation of some of the evidence presented.”

Ultimately, the ACIP deferred its vote on hepatitis B vaccine, preserving access to the birth dose for now. But in October, nearly all of the CDC staff that provided logistical support and subject-matter expertise to the ACIP was laid off, imperiling production of the 2026 vaccine schedules and making future departures from evidence-based recommendations more likely.

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This post first appeared on the AFP Community Blog. On December 2, the Vaccine Integrity Project posted an independent review of data on the efficacy, safety, and public health impact of hepatitis B vaccine at birth. In a decision analysis posted as a preprint, authors affiliated with the Hepatitis B Foundation projected that "delaying Hep B vaccination to 12 years for infants of both HBsAg-negative and HBsAg-unknown parents resulted in an additional 2,351 acute infections, 744 deaths, and $368 million in excess costs."