In today’s fast-paced and increasingly disconnected world, feelings of loneliness and social isolation have become all too common. While we often think of loneliness as an emotional state, new research from UCLA Health suggests that it can have profound effects on our physical health as well, particularly when it comes to our eating habits and risk of obesity. “Researching how the brain processes loneliness and how this is related to obesity and health outcomes hasn’t been done,” says senior study author Arpana Gupta, a researcher and co-director of the UCLA Goodman-Luskin Microbiome Center, in a media release.

Using functional magnetic resonance imaging (fMRI), UCLA Health researchers observed that when shown images of food, especially sweet treats, the brains of lonely individuals showed heightened activity in regions associated with processing internal states, such as hunger and appetite, as well as increased attention and motivation toward external food cues. At the same time, brain areas responsible for exerting self-control and making healthy decisions showed decreased activity. This imbalance in brain function may help explain why people who feel socially isolated are more likely to engage in unhealthy eating behaviors, such as having intense food cravings, using food as a reward, and even displaying signs of food addiction.

The study found that these altered brain responses were associated with a higher body fat percentage in lonely individuals. However, the impact of loneliness goes beyond just physical health. Researchers also discovered that the brain changes linked to social isolation were associated with poorer mental health outcomes, including increased anxiety and reduced positive emotions and psychological resilience. This suggests that loneliness may create a vicious cycle where unhealthy eating behaviors are used as a coping mechanism for dealing with the negative feelings that arise from feeling disconnected from others.

Dr. Gupta explains, “These findings are interesting because they provide evidence for what we intuitively know. When people are alone or lonely, it impacts more than how they are feeling; they underreport what they eat, their desire to eat, and their cravings, especially for unhealthy foods.” So why might feelings of loneliness lead to such dramatic changes in brain function and behavior? One theory is that when we feel socially isolated, our brains may enter a sort of “self-preservation mode.” This heightened state of vigilance and reactivity could drive us to seek out quick sources of comfort and energy, such as sugary or high-calorie foods. Over time, this pattern of eating can lead to weight gain and increase the risk of obesity-related health problems.

“If you have more cravings, you eat more and may have more anxiety or depression, which may lead you to eat more,” says study lead author Xiaobei Zhang, a postdoctoral researcher at UCLA Health Sciences. The findings of this study underscore the importance of addressing the growing problem of loneliness and social isolation in our society. While it may be tempting to turn to food for comfort during times of stress or loneliness, it’s crucial to find healthier ways to cope with these feelings and maintain social connections.