For generations, families across cultures have relied on simple, time-honored home remedies to comfort loved ones during cold and flu season, and among the most curious yet enduring of these traditions is the practice of sticking whole cloves into a peeled onion and leaving it in a room overnight. The advice is often delivered with quiet confidence, passed down from grandparents or older relatives who swear by its soothing effects: “Place a clove-studded onion near the bed, and it will help draw out the sickness.” At first glance, the ritual may sound like an artifact from a medieval apothecary or a relic of folk medicine rooted in superstition. Yet its persistence across generations suggests that it fulfills needs that extend beyond measurable medical outcomes. Before the rise of antibiotics, antiviral medications, and electric humidifiers, households relied heavily on sensory remedies—strong smells, warming broths, herbal infusions, and symbolic gestures—to create an environment of healing. The onion-and-cloves practice belongs to this lineage. While modern science does not support the idea that onions can “absorb” viruses from the air or that cloves can cure respiratory infections simply by sitting in a room, the ritual embodies a fusion of cultural tradition, chemistry, and psychological reassurance. It transforms ordinary kitchen ingredients into a symbolic act of protection and care. In an age when medical knowledge was limited and illness could feel mysterious and frightening, such rituals provided families with a sense of agency. Even today, when scientific explanations are readily available, the practice continues—not necessarily because people believe it performs miracles, but because it carries emotional resonance, familiarity, and comfort.

The traditional preparation of this remedy is remarkably simple, and its simplicity contributes to its accessibility and endurance. A whole onion—typically white or yellow—is peeled, exposing its moist, layered surface. Into this surface, six to twelve whole cloves are inserted, spaced evenly around the bulb like aromatic pins. The prepared onion is then placed on a saucer or shallow bowl and positioned near a bed, on a nightstand, or in a living space where someone is resting. It may remain there overnight or for up to two days before being discarded. Advocates of the remedy attribute a variety of benefits to this small act: they claim it absorbs germs from the air, clears nasal passages, neutralizes stale odors, and promotes deeper sleep. Historically, such beliefs were influenced by the once-dominant miasma theory, which held that diseases were spread through “bad air.” During outbreaks like the 1918 influenza pandemic, people reportedly placed sliced onions in rooms with the hope that they would trap harmful vapors. Although germ theory later clarified that viruses and bacteria spread through specific biological mechanisms rather than vague atmospheric corruption, the association between strong-smelling plants and purification persisted. In many cultures, aromatic substances—garlic, onions, herbs, and spices—were thought to repel illness. The clove-studded onion fits comfortably within that tradition. It required no specialized tools, cost very little, and symbolized attentive care. Even if the practice did not physically remove pathogens from the air, it offered something arguably just as valuable in times of uncertainty: the reassurance that someone was actively trying to help.

When examined through a scientific lens, onions and cloves do possess chemical properties that partially explain why the ritual might feel plausible. Onions are rich in sulfur-containing compounds that give them their sharp odor and cause tears when chopped. They also contain quercetin, a flavonoid antioxidant studied for its anti-inflammatory and antimicrobial properties. Laboratory research has demonstrated that onion extracts can inhibit certain bacteria—such as Escherichia coli and Staphylococcus aureus—when applied directly in controlled environments. However, these antimicrobial effects occur primarily in situations involving direct contact or concentrated extracts, not when an intact onion simply sits exposed in a room. The volatile compounds released into the air are minimal and disperse quickly, far below levels needed to neutralize airborne pathogens. Similarly, onions do not function as passive “sponges” that absorb viruses or bacteria floating in the air. Claims that an onion left overnight will turn dark because it has absorbed germs are explained more simply by oxidation and environmental moisture. Exposure to air causes enzymatic browning and textural changes, processes unrelated to disease capture. While onions undeniably contain biologically active compounds, the conditions under which they meaningfully inhibit microbes differ greatly from the context of a bedside remedy. Understanding this distinction helps separate the chemical reality from the folklore, without dismissing the cultural value of the tradition itself.

Cloves, too, contribute their own intriguing chemistry to the practice. Derived from the dried flower buds of the Syzygium aromaticum tree, cloves contain a potent compound known as eugenol. Eugenol has been studied extensively for its antibacterial, antifungal, anti-inflammatory, and mild antiviral properties. Clove oil remains in use today in dental settings for its numbing and antiseptic qualities, particularly for temporary relief of toothaches. The warm, spicy scent of cloves is not merely pleasant; it arises from volatile aromatic compounds that can stimulate sensory pathways in ways that feel soothing or invigorating. Yet, as with onions, the effectiveness of cloves depends on concentration and method of application. The antimicrobial benefits of eugenol are most pronounced when it is extracted and applied directly or used in sufficient vaporized concentrations. Whole cloves embedded in an onion release only trace amounts of aroma into a room, insufficient to disinfect the air or prevent infection. What they do provide, however, is a distinct sensory experience. The combined scent of onion and clove creates a pungent, warming atmosphere that some people perceive as clearing or invigorating. Smell is closely tied to memory and emotion, and familiar aromas can evoke feelings of safety, childhood, and care. In this way, cloves contribute less to pathogen elimination and more to environmental comfort. Their role in the ritual is symbolic as well as sensory—an aromatic reinforcement of the intention to nurture and heal.

Although the onion-and-cloves remedy lacks the medical potency often attributed to it, dismissing it outright overlooks subtler yet meaningful benefits. One of these benefits is mild aromatherapy. Strong scents can stimulate nasal passages and create the subjective impression of clearer breathing, even if they do not reduce viral load or inflammation. Additionally, onions naturally release a small amount of moisture as they sit exposed, which may slightly increase humidity in a confined space. While this effect is minimal compared to a dedicated humidifier, even small changes in air moisture can feel soothing in a dry bedroom, particularly during winter months when heating systems reduce indoor humidity. The ritual itself also carries psychological weight. Preparing the onion requires intentional action—peeling, placing cloves, arranging it carefully by the bed. These gestures communicate care and attention, reinforcing social bonds between caregiver and patient. Placebo effects, often misunderstood as imaginary, are in fact powerful demonstrations of the mind-body connection. When individuals believe they are being supported or protected, stress levels may decrease, and comfort may increase. Reduced stress can indirectly support immune function by lowering cortisol levels and improving rest. Thus, while the onion-and-cloves practice does not cure colds or prevent infection, it can create an environment conducive to rest and emotional reassurance. In times of illness, comfort itself is therapeutic.

It is equally important to clarify the limitations and safe use of this tradition. The clove-studded onion does not cure viral infections, shorten illness duration, eliminate airborne pathogens, or replace medical treatment and proper hygiene. Colds and influenza are caused by viruses that spread primarily through respiratory droplets and contact with contaminated surfaces, not through ambient “bad air” that can be absorbed by vegetables. Standard preventive measures—handwashing, adequate ventilation, vaccination when appropriate, and medical care when symptoms worsen—remain far more effective. Additionally, any onion left exposed for more than twenty-four to forty-eight hours can begin to harbor bacteria or mold due to its moisture content. For safety, it should be discarded promptly and never consumed after sitting out. Those who appreciate the aromatic qualities of onions and cloves might consider alternative methods that offer more tangible respiratory relief, such as simmering onion, garlic, cloves, and ginger in water to create steam. Inhaling warm steam increases humidity, helps loosen mucus, and provides temporary relief from congestion more effectively than a stationary raw onion. Yet even with these limitations acknowledged, the cultural and emotional dimensions of the clove-studded onion remain significant. It represents continuity between generations, a tactile expression of care, and a reminder that healing is not solely biochemical but relational. The remedy’s endurance speaks less to its antimicrobial power and more to its symbolic resonance. Ultimately, it is best understood not as a cure but as a comforting ritual—a small act of warmth that bridges folk wisdom and modern knowledge, preserving a sense of home and human connection in moments of vulnerability.