Wednesday, October 01, 2025

Loneliness in U.S. adults linked with amount, frequency of social media use

Oregon State University

Social media and loneliness — image:
TikTok, Instagram, Facebook and similar platforms are apparently no antidote for the global loneliness epidemic, according to Oregon State University research that linked increases in social media use with a greater likelihood of feeling alone.
view more
Credit: Steve Lundeberg, Oregon State University

CORVALLIS, Ore. – TikTok, Instagram, Facebook and similar platforms are apparently no antidote for the global loneliness epidemic, according to Oregon State University research that linked increases in social media use with a greater likelihood of feeling alone.

The study led by Jessica Gorman of the OSU College of Health, published today in the International Journal of Environmental Research and Public Health, featured more than 1,500 U.S. adults ages 30-70 and builds on a 2017 study by co-author Brian Primack that looked at young adults.

As in the previous study, two different measures of social media use – time and frequency – each correlated with loneliness; that is, many short “checks” are just as apt to be associated with loneliness as a few long sessions.

“I wasn’t sure if we would see as strong a relationship between social media and loneliness for 60-year-olds that we saw with 18-year-olds, but we did,” Primack said. “Those who were in the upper 25% based on frequency of social media use, compared with those in the lower 25%, were more than twice as likely to test as lonely.”

The findings have important public health implications, the authors say, given loneliness’ high cost to society. This is especially true because the study used survey weights to make the findings nationally representative of all U.S. adults.

Loneliness, characterized by the subjective experience of insufficient social connections and resources, is linked to a range of negative health consequences including cardiovascular disease, substance use, poor mental health and intimate partner violence. A 2023 advisory from the U.S. Surgeon General estimated the health impact of loneliness to be equivalent to smoking 15 cigarettes a day, and it identified social media use as a loneliness risk factor.

Americans were already growing lonelier before COVID-19, the authors note, and the pandemic worsened the trend. In the United States, an estimated 50% of the adult population is lonely.

“Most prior research on social media use and loneliness has focused on youth and young adults,” Gorman said. “Even after adjusting for all measured sociodemographic factors among the people in our study – gender, age, sexual orientation, educational attainment, employment status and marital status – we found a significant association between people being lonely and people being on social media frequently or for extended periods.”

For context, estimates suggest it’s not uncommon for a person to check in with social media between 100 and 200 times a day and to spend two to four hours on their platforms of choice. Older adults, as “digital immigrants,” may be less adept than younger social media users, which could be one factor behind the connection to loneliness in the older population, the researchers say.

“There hasn’t been enough research on adults, who use social media a lot and experience harm due to loneliness,” Primack said. “An important caveat is that this was a correlational study, so we can’t say whether using social media leads to loneliness or whether lonely people seek out more social media. It may be a combination.”

Although this study cannot determine why the connection exits, it does recommend caution around heavy social media use among U.S. adults, Gorman added. The results also suggest that, if it’s primarily a case of lonely people seeking out more social media, doing so doesn’t make the loneliness go away.

Also contributing to the study, which was funded by the National Institutes of Health, were OSU’s Hyosin Kim, Kari-Lyn Sakuma, Geethika Koneru, Memuna Aslam and Cesar Arredondo Abreu.

Journal

International Journal of Environmental Research and Public Health

DOI

10.3390/ijerph22101510

Method of Research

Survey

Subject of Research

People

Article Title

Time and Frequency of Social Media Use and Loneliness Among U.S. Adults

Article Publication Date

1-Oct-2025

Gene editing, traditional crossbreeding produce disease-resistant cacao plants

Novel approach could revolutionize sustainable chocolate production while addressing global food security, researchers report

Penn State

image:
Mycelium of phytophthora palmivora, which can give rise to cacao black pod disease, grows from an agar plug, infecting a cacao leaf 48 hours after inoculation.
view more
Credit: Mark Guiltinan/Penn State

UNIVERSITY PARK, Pa. — In a development that could help protect one of the world's most beloved agricultural commodities, a research team at Penn State has successfully created disease-resistant cacao plants using gene-editing technology. According to the researchers, the innovation promises to help resolve a significant problem for the global chocolate industry, worth over $135 billion annually, which faces threat from the phytophthora species, a fungal-like pathogen that gives rise to the destructive black pod disease that can cause yield losses of up to 30% worldwide.

In findings recently posted online in Plant Biotechnology Journal in advance of print publication this fall, the researchers reported that they edited the gene TcNPR3 in cacao plants, ultimately resulting in cacao plants that had 42% smaller disease lesions when infected with phytophthora, compared to non-edited plants.

“Cacao farmers, particularly those with limited economic resources, struggle to implement expensive disease-control measures,” said team leader Mark Guiltinan, professor of plant molecular biology in the College of Agricultural Sciences and first author on the study. “And many genetic modification approaches are met with stigma because foreign DNA is left in the final product. Our approach could solve both of those problems.”

The researchers employed CRISPR-Cas9, a gene editing technology that acts like “molecular scissors” to precisely modify DNA sequences in the genome, or the complete instructions encoding proteins and more, of living cells and organisms. This usually works by cutting unwanted genes out of the genome and splicing in transgenes, which are genes from other organisms or modified in the lab to achieve the desired functionality. However, this breakthrough represents the first demonstration of genome-edited, transgene-free cacao plants, meaning the plant’s DNA was altered without leaving any foreign DNA in the final product, addressing regulatory concerns and consumer acceptance.

The team specifically edited the gene TcNPR3, which is involved in the plant’s defense system, in plant cells, grew the cells into full plants and confirmed that they were less susceptible to the disease in lab tests using plant leaves, called foliar assays. The team crossed these edited plants with non-transgenic — normal cacao plants — resulting in non-transgenic offspring with the desired genetic changes. The researchers sequenced the genomes of parent and offspring plants and found that some offspring retained the beneficial gene edit but no longer had any foreign DNA — they were “clean” edits. The researchers analyzed the clean edits’ gene expression and found increased expression of genes involved in plant defense, with some genes downregulated, suggesting TcNPR3 may both suppress and activate certain genes.

“Our research team targeted the gene TcNPR3 because we learned from earlier studies that it acts as a molecular ‘brake’ on the plant’s natural defense system,” Guiltinan said. “NPR3 proteins — the family to which TcNPR3 belongs — are negative regulators of plant immunity, essentially preventing plants from mounting robust defenses against pathogens when they’re not immediately under attack.”

Think of NPR3 as a security system that’s set to “standby mode,” he explained. Disrupting the gene turns on its “high alert” mode, increasing the plant's natural defenses and making the plant less susceptible to pathogen attacks.

Perhaps more novel than using CRISPR-Cas9 technology to precisely mutate the TcNPR3 gene, Guiltinan said, was using traditional plant breeding to eliminate the foreign DNA sequences associated with the gene-editing machinery.

The result — cacao plants that contain only the desired genetic modifications without any transgenic elements — establishes a significant regulatory precedent, Guiltinan said, because the U.S. Department of Agriculture (USDA) has determined that these edited plants are not subject to biotechnology regulations since they contain no foreign genetic material — only precise edits to native cacao genes. After review of extensive data in the study manuscript, the USDA officially stated that it does not consider the genome-edited cacao lines to meet the same regulation requirements as genetically modified plants. However, the plants may still come under regulation by the U.S. Food and Drug Administration, Guiltinan said, “but that is down the line.”

This regulatory clarity removes a major barrier to adoption, Guiltinan suggested, adding that next the team will have to test the lines outside on research stations in tropical areas.

“We need to assess the plants’ performance outside of our greenhouses,” he said. “If successful, our hope is that someday soon, farmers and consumers can benefit from these disease-resistant plants to improve their livelihoods and protect the environment.”

Guiltinan and his team are assessing additional targets to increase disease resistance, as well as exploring new methods of genome editing, with the goal of developing a second generation of genome-edited cacao lines in the coming years.

“We're not just creating better cacao plants — we’re exploring how modern biotechnology can work within existing regulatory frameworks to address real-world agricultural challenges,” Guiltinan said. “Traditional breeding approaches are slow, often taking decades to develop new resistant varieties. For the millions of farmers who depend on cacao cultivation, and the billions who enjoy chocolate, this research offers hope for a more sustainable and secure future — one precise genetic edit at a time.”

Other members of the team contributing to the research were: Lena Landherr, assistant research professor in plant science; Siela Maximova, research professor of plant biotechnology and co-director of the Endowed Program in the Molecular Biology of Cocoa at Penn State’s Huck Institutes of the Life Sciences; Dante DelVecchio, graduate student in plant science; Aswathy Sebastian, bioinformatics analyst at the Huck Institutes; and Istvan Albert, research professor of bioinformatics at the Huck Institutes.

This research was supported by the Huck Institutes of the Life Sciences and the Penn State Endowed Program in the Molecular Biology of Cacao.

The fungal disease black pod rot, shown here in cacao seed pods, is a serious problem in all areas of the world where the crop is grown. Caused by the fungus phytophthora, black pod rot causes pod losses of up to 30% and kills as many as 10% of the trees annually.

Credit

Plant Village/Penn State