The Perfect Hug Length to Improve Immunity and Reduce Stress

A simple embrace acts as free medicine, even against viruses.

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In a carefully controlled laboratory at Carnegie Mellon University, researchers exposed more than 400 healthy volunteers to the common cold virus. However, before the viral exposure, researchers spent two weeks meticulously tracking something most scientists might overlook: whether the participants had been hugged each day.

The focus was not sentimental, but rather, to see whether a simple embrace could serve as a miniature vaccine against disease. The research, along with other studies, shows that the right frequency and duration of hugs can prime your immune system, lead to better heart health, and even help heal emotional wounds.

Can a Hug Defeat a Virus?

Carnegie Mellon’s study lead researcher, Sheldon Cohen, had a hunch that physical touch might be one of the key ways that social support protects us from stress-induced illness.

His team exposed participants to the common virus and, for 14 consecutive days, asked them about their daily conflicts, social interactions, and, yes—whether anyone had hugged them that day.

The results: Cohen’s hypothesis proved prescient. Participants who were hugged on most days had about 60 percent lower odds of becoming infected than those who were rarely hugged. Additionally, those who did get sick recovered more quickly and had stronger immune responses than those who received fewer hugs.

These findings suggest that hugging, in addition to being an affectionate human behavior, is also a surprisingly effective defense against stress-related illness, boosting the immune system.

The Science Behind the Embrace

When we hug someone, a cascade of events unfolds in our bodies and brains, affecting us on multiple levels—neurobiological, neurochemical, and social.

Neurobiologically, hugging stimulates a network of sensory nerves under the skin, particularly a specialized group called C-tactile afferents, sometimes referred to as “cuddle nerves.”

These nerves are especially responsive to gentle, affectionate touch and send signals directly to the insular cortex, the brain’s center for emotional processing. When triggered, cuddle nerves also release endorphins, the body’s natural painkillers that help boost mood. Cuddle nerves are optimized to create a sensation of comfort, reinforcing our drive to seek and enjoy close physical contact with others.

On a neurochemical level, hugging triggers the release of several “feel-good” chemicals. Chief among these is oxytocin, often dubbed the “love hormone,” which enhances feelings of bonding, trust, and safety.

In addition, hugging releases dopamine, which is associated with pleasure, and serotonin, which stabilizes mood and promotes happiness. From a social and psychological standpoint, hugs convey support without the need for words, serving as nonverbal affirmations of shared emotion, reinforcing social bonds.

When researchers tested different types of hug styles and durations, they discovered precise requirements: one-second hugs felt unsatisfying and provided minimal benefit. At the same time, five to 10 seconds proved optimal before longer contact became uncomfortable.

For intimate relationships, 20-second embraces produce the strongest measurable effects.

Health Benefits Wrapped in Every Hug

In a 2023 study published in the International Journal of Environmental Research and Public Health, more than 100 first-year college students who received more daily hugs from friends, roommates, and family members had reduced morning stress levels the following morning compared with days when they received fewer hugs.

Conny Wade, a functional medicine practitioner and health coach, said physical touch also improves cardiovascular health by increasing heart rate variability (HRV).

“Heart rate variability is a crucial measure of how well your body responds to stress. Your HRV should be as high as possible,” she told The Epoch Times.

Earlier research from 2003 found that couples who had 10 minutes of hand holding followed by a 20-second hug with their partner before giving a speech had lower blood pressure and heart rate by half compared with those who sat quietly without contact. These results suggest that affectionate touch provides physiological protection, which partially explains the heart health benefits associated with supportive relationships.

Regular affectionate contact produces benefits that extend far beyond stress reduction and a healthier heart. People who receive consistent physical comfort—whether from humans, pets, or even weighted blankets—sleep more soundly and wake more refreshed than those lacking such contact.

Hugging on a regular basis can also help reduce inflammation, Wade said.

“Inflammation is largely caused by chronic stress, and chronic inflammation has been connected to a variety of health issues, including depression and autoimmune diseases,” she said.

Indeed, a 2020 study found that hugging was significantly associated with lower pro-inflammatory molecules.

Healing Trauma Through Touch

Mental health specialist Stacey Ross witnessed profound transformations when her clients with anxiety, depression, post-traumatic stress disorder, and addiction received a gentle, comforting touch.

“[It] can remind their brain what it feels like to be safe and loved,” Ross told The Epoch Times.

This isn’t merely psychological. Neuroplasticity research shows that repeated positive experiences reshape neural pathways.

Healing happens because consistent physical comfort creates new neural patterns that support emotional recovery. The brain’s ability to change and adapt through experience means that regular affectionate touch can gradually rewire damaged stress responses and emotional regulation systems.

For trauma survivors, physical affection provides a pathway to healing that bypasses the need to process painful memories through words alone.

Regardless of context, hugging is a powerful tool for enhancing well-being across all ages. The prescription requires no special training, expensive equipment, or pharmaceutical intervention. Next time you feel like taking medicine, remember the one that’s just around your shoulders.