What causes a bad odor on the face?

Generally, an unusual odor on the face may be caused by inadequate cleansing, excessive hormone secretion, seborrheic dermatitis, periodontitis spreading to facial areas, or secondary infection from rosacea. It is recommended to seek medical attention promptly, identify the underlying cause, and receive appropriate treatment under a doctor's guidance. Specific analyses are as follows:

1. Inadequate Cleansing: When facial oils, sweat, dust, and residual cosmetics accumulate over time, they can promote bacterial growth that produces odor. Cleanse your face every morning and evening with a gentle facial cleanser, paying special attention to oily areas such as the T-zone. After wearing makeup, use a proper makeup remover to thoroughly cleanse the skin and prevent clogged pores.

2. Excessive Hormone Secretion: Hormonal fluctuations during puberty or menstruation can increase sebaceous gland activity, leading to excess oil production and subsequent odor after oil breakdown. Maintain a regular sleep schedule and avoid staying up late. Eat a light diet, reduce intake of high-fat and high-sugar foods, use oil-control and moisturizing skincare products, and periodically blot excess facial oil with oil-absorbing sheets.

3. Seborrheic Dermatitis: Abnormal sebum secretion triggers inflammation, resulting in greasy red patches on the face accompanied by flaking and odor. Patients should follow medical advice to apply medications such as tacrolimus ointment, pimecrolimus cream, or vitamin B6 ointment, and choose fragrance-free, gentle skincare products.

4. Periodontitis Spread: Odors produced by bacteria in periodontal disease can spread through the respiratory tract to the face, particularly noticeable around the nose and mouth area. Patients should use prescribed medications such as metronidazole mouthwash, amoxicillin capsules, or tinidazole tablets, maintain oral hygiene with regular teeth cleaning, and rinse the mouth after meals.

5. Secondary Infection from Rosacea: Rosacea causes blood vessel dilation and compromises the skin barrier, making it prone to secondary bacterial infections that produce odor. Follow a physician’s instructions to use medications such as clindamycin gel, doxycycline tablets, or azelaic acid cream. Avoid sun exposure and irritating foods like spicy dishes.

In daily life, keep indoor spaces well-ventilated and avoid hot, humid environments that worsen oiliness. Carry a gentle hydrating facial mist for timely moisture replenishment. Drink plenty of water to support metabolism, and maintain both oral and facial cleanliness to reduce odor at its source.