Flies are drawn to the human face because it offers a combination of warmth, moisture, and readily available nutrients. The warmth from your body, especially the heat around the head, is a strong signal for insects seeking a host. Flies are also attracted to the carbon dioxide you exhale, which helps them locate you. Your face provides a rich source of sweat, containing salts, proteins, and sugars that flies consume for hydration and nourishment. To gain relief from these pests, employ strategies involving physical exclusion, topical repellents, and managing personal attractants.
Physical Barriers for Protection
Physical shields are one of the most effective non-chemical methods for keeping flies away from your face. Head nets are a simple, portable solution that completely isolates your head from surrounding insects. These nets are typically made of polyester or nylon mesh and include a drawstring to secure the bottom around your neck or shirt collar.
For maximum protection against the smallest pests like gnats, midges, and no-see-ums, look for an ultra-fine mesh with a density of at least 900 holes per square inch (psi). When using a head net, wear a wide-brimmed hat underneath. The brim keeps the netting away from your skin, preventing flies from landing and biting through the mesh where it touches your face.
The choice of clothing and headwear can also serve as a barrier. A wide-brimmed hat, even without a net, offers protection by shielding your face and creating a moving shadow that can disrupt a fly’s approach. Wearing light-colored clothing is recommended, as darker colors tend to absorb more heat and may be more attractive to some insects. Ensuring your shirt collar is high or using a buff/neck gaiter can prevent flies from crawling up from the neck area to the face.
Applying Topical Repellents
Topical insect repellents offer a reliable chemical defense, but they must be applied correctly, especially around the sensitive facial area. The most effective active ingredients include DEET, Picaridin (or Icaridin), and Oil of Lemon Eucalyptus (OLE/PMD). Repellents work by creating a vapor barrier that confuses the fly’s sensory organs, masking the attractive scents of your skin and breath.
Never spray a repellent directly onto your face, as this risks inhalation and direct contact with the eyes and mouth. Instead, spray a small amount onto your hands first, and then carefully rub a thin, even layer onto exposed facial skin. When using lotions or creams, apply a small amount to your fingertips and lightly spread it across your forehead, cheeks, and chin.
Avoid applying repellent near your eyes, nostrils, or mouth, and use it sparingly around your ears. Do not apply repellent over cuts, wounds, or irritated skin, as this increases the risk of irritation or absorption. For most situations, a concentration of 20% to 30% DEET or 10% to 20% Picaridin provides sufficient protection and longevity. Applying more than the recommended amount does not increase efficacy but may increase the potential for skin irritation.
Minimizing Attractants
Flies rely heavily on scent and chemical cues to locate food and moisture sources, so managing your personal environment helps reduce your attractiveness. Human sweat contains salts, lactic acid, and other organic compounds that flies seek out for nutrients. Wiping down your face with a cool cloth or using a fan to increase evaporation minimizes the buildup of these attractive secretions.
Flies are also drawn to specific odors, including highly scented products like perfumes, colognes, and some hairsprays or lotions. Avoiding these strong fragrances when spending time outdoors significantly reduces the number of flies that approach your head and face. Similarly, the plume of carbon dioxide you exhale serves as a long-range beacon for many flying insects.
While you cannot stop breathing, managing your exertion level can help. Reduced physical activity leads to less heavy breathing and less sweat production, lowering the intensity of these attractant signals. Certain natural scents like eucalyptus, peppermint, and lavender are known to be repulsive to flies, and incorporating these into your routine provides an extra layer of defense.