Oromia, Ethiopia — Irreechaa is the annual Oromo thanksgiving festival celebrated at the banks of rivers and lakes across Oromia. Its rituals — communal chanting, the dipping of fresh green grass into water, and the gathering of communities at the water’s edge — are not merely symbolic acts of cultural identity. A growing body of scientific research reveals that these elements engage powerful psychophysiological mechanisms that promote mental well-being, reduce stress, and foster social connection.

The Sound of Chanting: Reducing Stress and Anxiety

Chanting, a central practice in Irreechaa’s riverside ceremonies, has been shown to produce measurable reductions in stress and anxiety. A randomized controlled trial conducted in Australia found that just twelve minutes of group chanting — whether vocal or silent — resulted in significant decreases in cortisol levels and self-reported anxiety . The reduction in cortisol, the body’s primary stress hormone, was similar for both vocal and silent chanting. However, self-reported anxiety decreased more following vocal chanting, suggesting that the act of voicing — singing the Marewoo songs of Irreechaa — amplifies the psychological benefit .

The study also found that altruism scores increased following both vocal and silent chanting, indicating that the ritual practice fosters pro-social tendencies . Group synchronisation, a feature of communal chanting, is thought to promote cooperation and feelings of connection to others . This aligns with the experience of Irreechaa participants, who sing together in a shared expression of gratitude and hope.

Research specifically examining Irreechaa notes that “chanting reduces stress hormones and triggers dopamine, promoting transcendence” . The sonic dimensions of the ritual, combined with its setting at the water’s edge, create what researchers describe as an immersive environment that unites communities and reinforces cultural identity .

The Touch of Fresh Grass: Tactile Contact and Relaxation

The fresh green grass carried by Irreechaa participants — dipped into the water as an offering and symbol of renewal — also carries documented psychological benefits when touched. A 2024 study published in the Journal of Urban Health investigated the effects of tactile interaction with real grass versus artificial grass among older adults. The findings showed that touching real grass produced a heightened sense of relaxation and calmness, increased mean systolic blood pressure reduction, and upward trends in brainwave patterns associated with relaxation .

A separate study involving young adults found that five minutes of tactile stimulation with real landscape grass, applied through the palm of the hand, produced significant reductions in diastolic blood pressure, increased alpha brainwave activity (a marker of relaxed alertness), and alleviation of anxiety compared to a control condition . The researchers concluded that “palming grass — the act of touching grass with one’s hand — has a calming effect on both physiological and psychological responses to stress” .

For Irreechaa participants, the act of holding grass and dipping it into the water is thus not only a spiritual gesture but a tactile experience with measurable calming effects on the nervous system.

The Presence of Water: Blue Space and Restoration

Irreechaa’s setting at rivers and lakes — Irreechaa Malkaa — places participants in what researchers call “blue spaces,” environments featuring water. A systematic evidence map of blue space research confirms that contact with water environments is associated with mental health benefits, including reduced stress and enhanced well-being .

A landmark 19-country study involving over 17,000 participants found that all blue space settings were recalled as restorative, with rural rivers and canals among the most restorative . Perceived safety was the quality most strongly associated with restoration, and actively engaging with the water was associated with greater restoration than remaining on land . The study also found a reciprocal relationship between restoration and nature connectedness — the more restored an individual felt, the more connected to nature they became, and vice versa .

Research specifically examining Irreechaa notes that “water’s acoustic properties (transmitting sound four times faster than air) create immersive ritual environments,” and that the natural water setting “engages biophilia, enhancing mental well-being” . The riverside location of Irreechaa thus amplifies both the sonic and the restorative dimensions of the festival.

The Synergy of Sound, Grass, and Water

What makes Irreechaa psychologically powerful is not any single element in isolation, but their combination. The ritual brings together vocal chanting, tactile contact with fresh grass, and immersion in a water environment — a multisensory experience that engages multiple pathways to well-being simultaneously.

Research on Irreechaa explicitly describes this synergy: “water’s fluidity and reflectivity, paired with the resonance of sound, create multisensory rituals that deepen spiritual engagement” . The study notes that “psychologically, chanting and singing reduce stress and trigger dopamine release, fostering emotional uplift and communal bonding,” while “natural water settings engage biophilia, enhancing mental well-being and aligning with the spiritual clarity sought in rituals” .

The communal dimension is equally important. Group chanting, being a synchronous activity, promotes feelings of social connection and altruistic tendencies . For a community gathering after the isolating rainy season, this reconnection — through shared sound, shared touch of grass, and shared presence at the water — serves as a collective psychological renewal.

A Culturally Rooted Pathway to Well-Being

For the Oromo people, Irreechaa is a spiritual and cultural celebration. The scientific evidence now confirms what generations have experienced intuitively: the ritual’s elements — sound, grass, and water — are also powerful tools for mental health. In a context where formal mental health services are scarce, Irreechaa offers an accessible, culturally meaningful pathway to stress relief, emotional restoration, and social connection.

The psychological power of Irreechaa lies in its integration of body, mind, and community — a holistic approach to well-being that modern research is only beginning to fully understand.