Orange Tongue: Causes, Symptoms, and Treatments

An unusual orange tint on your tongue can be surprising, but it's often a temporary and harmless issue. While a healthy tongue is typically pink with a thin whitish coating, various factors can cause it to change color. In many cases, an orange tongue is simply related to diet or oral care habits. However, it can sometimes signal an underlying health concern that needs attention. The human mouth is a complex ecosystem housing billions of bacteria, fungi, and viruses that make up the oral microbiome. When this delicate balance is disrupted—whether by external substances, internal physiological shifts, or systemic illness—the visible characteristics of your oral tissues, particularly the highly vascular and textured surface of the tongue, can change dramatically. Monitoring these changes provides valuable, non-invasive insight into your overall physiological state.

This article explores the common causes of an orange tongue, associated symptoms, effective treatments, and prevention strategies to help you understand what this change might mean for your health. We will delve into the anatomical and microbiological mechanisms behind tongue discoloration, examine how everyday habits and medical conditions contribute to the phenomenon, and outline evidence-based approaches to restoring a healthy oral environment.

What is an Orange Tongue?

An "orange tongue" refers to a noticeable orange discoloration on the top surface of the tongue. This can appear as a light yellow-orange film, a bright orange coating, or rusty-colored patches. The tongue's surface is covered in tiny bumps called papillae, which can trap food debris, bacteria, and dead cells. When these substances accumulate, they can create a colored coating. Underneath the visible coating, the tongue's mucosa remains richly supplied with blood vessels, nerves, and specialized sensory receptors that govern taste, texture, and temperature perception.

While a white or yellow coating is more common, an orange hue can develop under certain conditions. Most causes are related to a surface coating that can be cleaned off, but persistent discoloration should be evaluated by a healthcare professional. From a clinical perspective, the orange coloration typically stems from one of three pathways: exogenous staining (pigments adhering to the keratinized surface of filiform papillae), endogenous microbial pigmentation (chromogenic bacteria or fungi producing carotenoid-like compounds), or physiological changes in salivary composition and oral pH that alter light reflection and bacterial colonization patterns. Understanding which pathway is active is crucial for determining whether simple hygiene adjustments will suffice or if targeted medical intervention is required.

Common Causes of an Orange Tongue

Several factors, ranging from your diet to underlying medical conditions, can cause your tongue to turn orange. The following breakdown details the clinical mechanisms behind each cause, helping you identify potential triggers in your daily life or medical history.

1. Dietary Factors and Food Dyes

One of the most frequent causes is consuming foods or drinks with strong natural or artificial pigments. The filiform papillae on the dorsal surface of the tongue act like microscopic bristles, easily trapping particulate matter and liquid dyes. When highly concentrated pigments come into prolonged contact with these keratinized structures, they adhere rapidly and create a vivid discoloration.

• Colored Foods & Drinks: Orange soda, sports drinks, popsicles, and hard candies can temporarily stain the tongue. Many commercial beverages contain synthetic dyes such as Sunset Yellow (E110), Orange B, or Red 40 mixed with Yellow 5 to achieve vibrant shades. These food colorants are water-soluble and bind readily to the glycoproteins in saliva and the epithelial surface.
• Foods Rich in Beta-Carotene: A high intake of foods like carrots, sweet potatoes, and pumpkins can sometimes impart an orange tint to the tongue and skin. Beta-carotene is a fat-soluble precursor to vitamin A that accumulates in tissues when consumed in excess. While typically associated with a generalized yellow-orange skin condition known as carotenoderma, localized oral staining occurs when concentrated carotenoid-rich juices or purees coat the tongue.
• Spices: Potent spices like turmeric, a key ingredient in curry, are known for their strong yellow-orange color and can easily stain your tongue. Curcumin, the active compound in turmeric, has a pronounced affinity for mucous membranes and dental enamel. Similarly, paprika, annatto, and saffron can leave temporary residues, especially when consumed in concentrated powder form or used in traditional cooking methods that involve prolonged simmering and coating of food particles.

If your orange tongue appears after eating, it is likely a temporary stain that can be removed by brushing your tongue and rinsing your mouth. Hydration and gentle mechanical debridement are usually sufficient to clear dietary pigments within 24 hours.

2. Poor Oral Hygiene

Inadequate oral care allows bacteria and food debris to build up on the tongue's surface. Certain pigment-producing bacteria (chromogenic bacteria) can thrive in this environment, creating a yellow, brown, or orange coating. The human tongue naturally harbors hundreds of bacterial species, but poor cleaning habits disrupt the normal desquamation process, where old epithelial cells naturally slough off. When this shedding is delayed, the papillae elongate, creating a rougher, more retentive surface.

A related condition is Black Hairy Tongue, where dead skin cells accumulate on the papillae, causing them to elongate. Although named for its dark appearance, this condition can also look brown, yellow, or orange if stained by food or bacteria. The elongated filiform papillae lose their natural exfoliation cycle due to mechanical friction absence, altered salivary pH, or oxidative stress. Chromogenic microorganisms such as Serratia marcescens, Bacillus species, and certain strains of Porphyromonas can colonize this hypertrophied tissue. These microbes produce metabolic byproducts, including porphyrins and carotenoids, that manifest as vivid surface pigmentation. Addressing the underlying hygiene deficit typically reverses the condition within one to two weeks.

3. Oral Thrush (Yeast Infection)

Oral thrush is a fungal infection caused by an overgrowth of Candida albicans yeast. It typically appears as creamy white patches on the tongue and inner cheeks. However, these patches can become stained by food or mix with bacterial pigments, giving them a yellowish or orange hue. Candida species are opportunistic commensal organisms, meaning they reside harmlessly in healthy mouths but proliferate rapidly when ecological balance is disturbed. The fungus forms biofilms that adhere tightly to the oral mucosa, creating a thick, adherent plaque.

Individuals with weakened immune systems, diabetes, or those taking antibiotics or corticosteroids are at a higher risk for oral thrush. Elevated blood glucose levels in poorly controlled diabetes provide a nutrient-rich environment for yeast proliferation. Broad-spectrum antibiotics eliminate competitive bacterial flora, while inhaled or systemic corticosteroids suppress local immune responses in the oral cavity. When thrush develops an orange tint, it often indicates a secondary bacterial colonization of the fungal plaques, creating a mixed biofilm that reflects light differently. Clinically, these stained plaques may not scrape off as easily as dietary debris and may leave an erythematous, sometimes bleeding base upon removal.

4. Acid Reflux (GERD)

Gastroesophageal reflux disease (GERD) allows stomach acid to flow back into the esophagus and mouth. This acidic environment can alter the oral microbiome and irritate the tongue, sometimes leading to a yellow or orange coating, particularly in the morning. The human mouth maintains a slightly alkaline resting pH (around 6.5 to 7.5), which supports healthy enzymatic activity and bacterial diversity. Chronic exposure to gastric contents, with a pH as low as 1.5 to 3.5, disrupts this equilibrium, causing mucosal irritation and compensatory changes in salivary composition.

If GERD is the cause, you may also experience heartburn, a sour taste, or a sore throat. The refluxate often carries partially digested food particles, bile salts, and pepsin, all of which can deposit on the posterior third of the tongue. Additionally, the inflammatory response triggered by repeated acid exposure increases local blood flow and mucosal permeability, making the tissue more susceptible to staining from dietary residues and oral bacteria. Nighttime reflux is particularly problematic, as swallowing frequency decreases during sleep, allowing acidic material to pool in the pharynx and coat the dorsal tongue surface. Managing reflux through dietary modifications, elevation of the head of the bed, and proton pump inhibitors often resolves the accompanying oral discoloration.

5. Dry Mouth (Xerostomia)

Saliva is essential for cleaning the mouth and controlling bacteria. When you don't produce enough saliva, a condition known as dry mouth or xerostomia, bacteria and debris can accumulate on the tongue, forming a colored coating. Saliva serves as a natural mechanical cleanser, antimicrobial agent, and buffer. It contains immunoglobulins (IgA), lysozyme, lactoferrin, and mucins that continuously wash away microorganisms and prevent adhesion to oral surfaces. When salivary flow diminishes, these protective mechanisms fail, allowing rapid biofilm maturation and pigment deposition.

Dry mouth can be caused by:

• Dehydration
• Mouth breathing
• Certain medications (antihistamines, antidepressants, diuretics, antihypertensives)
• Medical conditions like Sjogren’s syndrome
• Radiation therapy to the head and neck region

Saliva production naturally decreases with age, and polypharmacy is a leading cause of drug-induced xerostomia. Over 400 commonly prescribed medications list dry mouth as a side effect. The resulting viscous, minimal saliva fails to adequately rinse the tongue, causing keratin buildup and creating an ideal environment for pigmented microorganisms. Patients with chronic xerostomia often develop a thickened coating on the mid-dorsal tongue that ranges from yellow to orange. Artificial saliva substitutes, sugar-free xylitol lozenges, and prescription sialagogues like pilocarpine can stimulate flow and restore natural cleansing mechanisms.

6. Smoking and Tobacco Use

Tobacco products contain tar and nicotine that stain teeth and the tongue's surface, often resulting in a brown, yellow, or orange color. Tobacco smoke introduces thousands of chemical compounds into the oral cavity, including polycyclic aromatic hydrocarbons, heavy metals, and reactive oxygen species. These substances directly damage the epithelial lining of the mouth and impair local immune surveillance, increasing susceptibility to microbial overgrowth and keratin hyperplasia.

Smoking also contributes to dry mouth and alters the balance of oral bacteria, increasing the likelihood of discoloration. The heat and chemical irritation from tobacco stimulate compensatory hyperkeratinization, where the tongue produces excess protective keratin. This thicker keratin layer is more prone to trapping tar particles and bacterial byproducts. Vaping and smokeless tobacco are not exempt from causing oral discoloration; flavoring agents, propylene glycol, and nicotine salts can still alter oral pH, reduce salivary flow, and deposit colored residues. Cessation remains the most effective intervention, with noticeable improvement in tongue color and texture typically occurring within two to four weeks of complete tobacco abstinence.

7. Medications and Supplements

Certain substances can discolor your tongue:

• Antibiotics: Some antibiotics, like rifampin, can turn bodily fluids, including saliva, orange. Others can disrupt oral flora, allowing pigment-producing bacteria or yeast to overgrow. Rifampin and rifabutin specifically bind to red blood cells and tissues, producing a characteristic orange-red hue that is completely harmless and reversible. Tetracyclines and broad-spectrum penicillins may indirectly cause discoloration by eliminating commensal bacteria that normally compete with chromogenic species.
• Bismuth Subsalicylate: Found in products like Pepto-Bismol, this ingredient can cause a temporary black or dark-orange discoloration on the tongue. Bismuth reacts with trace amounts of sulfur produced by oral bacteria to form bismuth sulfide, which appears as dark specks or a diffuse coating. As the compound degrades and mixes with oral debris, it can present as a rusty orange-brown shade.
• Vitamins and Supplements: High-dose vitamin B supplements or liquid iron can sometimes stain the tongue. Chewable vitamins with added dyes can also be a culprit. Iron supplements, particularly ferrous sulfate liquid formulations, contain strong oxidizing properties that can temporarily tint the oral mucosa. Multivitamin formulations often use food-grade colorants that adhere to tongue papillae, especially when the tablets are allowed to dissolve on the tongue before swallowing.

8. Other Underlying Health Conditions

In rare instances, an orange tongue may signal a systemic health issue:

• Jaundice: Caused by high levels of bilirubin in the blood due to liver or gallbladder problems, jaundice turns the skin and whites of the eyes yellow. It can also cause a yellow-orange tinge on the mucous membranes, including the tongue. Bilirubin accumulation occurs when hepatic excretion is impaired, red blood cell breakdown accelerates, or biliary obstruction prevents normal pigment elimination. When serum bilirubin exceeds 2.5 mg/dL, mucosal tissues begin to exhibit visible pigmentation. This presentation requires immediate clinical evaluation, as it often indicates hepatitis, cirrhosis, choledocholithiasis, or hemolytic anemia.
• Geographic Tongue: This harmless condition creates map-like patches on the tongue. While the patches are typically red or pink, they can sometimes appear orange or become stained by food. Also known as benign migratory glossitis, it involves localized loss of filiform papillae, creating smooth, erythematous areas with slightly raised, white or yellow-orange borders. The exact etiology remains unclear, but it is strongly associated with psoriasis, fissured tongue, and certain genetic markers. The altered surface topography of affected patches readily absorbs dietary pigments, resulting in transient orange discoloration during active phases.

Symptoms Associated with an Orange Tongue

Pay attention to other symptoms that can help identify the cause. The clinical presentation of tongue discoloration rarely occurs in isolation. Associated symptoms provide crucial diagnostic clues that differentiate benign staining from pathological conditions requiring intervention.

• Visible Coating or Furry Texture: Suggests a buildup of debris or black hairy tongue. A coating that scrapes off easily with minimal bleeding typically indicates superficial staining or mild microbial overgrowth. If the coating is thick, tenacious, or leaves an erythematous base after removal, fungal or bacterial biofilm involvement is more likely.
• Bad Breath (Halitosis): Often linked to bacterial overgrowth. Volatile sulfur compounds produced by anaerobic bacteria metabolizing proteins on the tongue are the primary culprits. Persistent halitosis accompanying orange discoloration strongly suggests inadequate desquamation and active microbial fermentation on the dorsal tongue surface.
• Taste Changes: A metallic, foul, or acidic taste may accompany the discoloration. Altered gustatory function, or dysgeusia, frequently occurs when the papillae are coated with biofilm or when systemic conditions like GERD or medication use alter receptor sensitivity. Patients often report diminished sweet or salty perception and heightened bitterness.
• Soreness or Pain: Can indicate an infection like thrush or another form of inflammation (glossitis). Pain suggests mucosal breach, immune activation, or neuropathic irritation. Burning mouth syndrome, nutritional deficiencies (particularly B12, iron, or folate), and localized infections all present with discomfort that correlates with visible changes.
• Dry Mouth: A sticky, parched feeling points to xerostomia. Reduced salivary clearance directly correlates with coating thickness. Patients may report difficulty swallowing dry foods, increased water intake, or reliance on artificial moisturizers.
• Systemic Symptoms: Fever, sore throat, or yellowing of the skin/eyes warrants immediate medical attention. Constitutional symptoms indicate that the oral manifestation is part of a broader systemic process, such as infectious mononucleosis, viral hepatitis, or autoimmune dysregulation.

When to See a Doctor or Dentist

While often harmless, you should seek professional advice if specific thresholds are met or warning signs emerge. The mouth is frequently the first anatomical region to display manifestations of systemic disease, making professional evaluation essential when home management fails.

• The orange color persists for more than a week despite good oral hygiene.
• You experience pain, soreness, or difficulty swallowing.
• You have a fever, yellowing of the skin or eyes, or other systemic symptoms.
• The tongue has a very thick, hairy coating that doesn't improve.
• You have a weakened immune system or other chronic medical conditions.

During a clinical evaluation, your dentist or physician will perform a comprehensive oral examination, assess your medical and medication history, and evaluate for signs of systemic disease. They may utilize special lighting, magnification, or intraoral photography to document changes. If an infectious process is suspected, a swab for Gram stain, fungal culture, or rapid antigen testing may be performed. Blood work could be ordered to check liver function, glucose levels, nutritional markers, or autoimmune antibodies if indicated. Early intervention prevents complications such as deep tissue infection, persistent dysgeusia, or progression of undiagnosed systemic conditions.

Diagnosis and Treatment

A healthcare provider will diagnose the cause through a physical examination and medical history. In some cases, a tongue swab or blood test may be necessary. Treatment focuses on addressing the underlying cause, and clinical protocols are highly individualized based on diagnostic findings.

• Improve Oral Hygiene: Gently brush your tongue with a soft-bristled toothbrush or use a tongue scraper daily. Mechanical debridement should be performed using gentle, front-to-back strokes to avoid gag reflex stimulation or mucosal trauma. Copper or stainless steel scrapers are often recommended over plastic due to their antimicrobial properties and superior biofilm removal efficiency. Over-scrubbing should be avoided, as it can cause microabrasions that facilitate pathogen entry and worsen inflammation.
• Stay Hydrated: Drink plenty of water to combat dry mouth and help rinse away debris. Aim for 8 to 10 glasses of water daily, adjusting for activity level and climate. Sipping water throughout the day maintains mucosal hydration better than consuming large volumes intermittently. Adding a pinch of salt and baking soda can create a mild alkaline rinse that neutralizes acids and loosens adherent debris.
• Adjust Your Diet: Avoid foods and drinks known to cause staining. Rinsing your mouth with water after meals can help. Incorporating fibrous, crunchy foods like apples and raw vegetables can provide natural mechanical cleaning during mastication. Limiting refined sugars reduces substrate availability for fermentative bacteria that contribute to biofilm thickness and pigment production.
• Treat Infections: Oral thrush requires antifungal medication, while other bacterial issues may resolve with improved hygiene or medicated mouthwashes. Nystatin oral suspension or clotrimazole troches are first-line for candidiasis, typically prescribed for 7 to 14 days. For severe or refractory cases, systemic fluconazole may be necessary. Chlorhexidine gluconate rinses (0.12%) are effective for bacterial overgrowth but should be limited to short-term use to prevent staining and taste alteration.
• Manage GERD: Lifestyle changes and medications like antacids or PPIs can control acid reflux. Avoid eating within three hours of bedtime, elevate the head of your bed by 6 to 8 inches, and identify dietary triggers such as caffeine, alcohol, spicy foods, and fatty meals. Proton pump inhibitors reduce gastric acid production, while alginates form protective rafts that prevent refluxate from reaching the oral cavity.
• Quit Tobacco: Quitting smoking or chewing tobacco will improve tongue color and overall oral health. Nicotine replacement therapy, varenicline, and behavioral counseling significantly increase long-term cessation success. Within 48 hours of quitting, taste and smell receptors begin to regenerate, and mucosal blood flow normalizes, accelerating tissue healing.
• Address Medical Conditions: If the cause is a systemic issue like jaundice, treating the underlying condition is crucial. Multidisciplinary care involving hepatologists, gastroenterologists, or endocrinologists may be required. Resolution of oral symptoms typically parallels improvement in systemic markers once targeted therapy is initiated.

Watch a Video: How to Clean Your Tongue Properly

How to Prevent an Orange Tongue

Maintaining a healthy, pink tongue involves consistent good habits. Prevention strategies should focus on supporting oral microbiome diversity, optimizing salivary function, and minimizing exposure to exogenous irritants and staining agents.

• Clean Your Tongue Daily: Make tongue scraping or brushing part of your routine. Incorporate it after morning tooth brushing and before evening bedtime cleaning to remove overnight biofilm accumulation and daytime debris. Consistency is key; sporadic cleaning allows microcolonies to mature and produce visible pigmentation.
• Practice Good Oral Hygiene: Brush your teeth twice a day and floss daily. Use fluoride toothpaste and replace your toothbrush every three to four months, or sooner if bristles become frayed. Consider an electric toothbrush with oscillating-rotating heads for superior plaque removal. Daily interdental cleaning reduces the overall bacterial load that can migrate to the tongue surface.
• Stay Hydrated: Drink sufficient water throughout the day. Monitor urine color as a hydration indicator; pale yellow suggests adequate intake. Limit diuretic beverages like excessive coffee and alcohol, which can exacerbate fluid loss and reduce salivary secretion. Chewing sugar-free gum stimulates parasympathetic salivary flow, providing continuous natural cleansing.
• Eat a Balanced Diet: Limit sugary and artificially colored foods. Prioritize antioxidant-rich fruits and vegetables, lean proteins, and whole grains. Probiotic-rich foods like yogurt, kefir, and fermented vegetables can help restore healthy bacterial balance. Adequate intake of B vitamins, iron, and zinc supports rapid epithelial turnover and maintains mucosal integrity.
• Avoid Tobacco: Quitting is one of the best things you can do for your oral and overall health. If cessation is challenging, consult healthcare providers about pharmacological aids and support programs. Avoiding secondhand smoke exposure also reduces environmental irritation and oxidative stress to oral tissues.
• Get Regular Dental Check-ups: A dentist can spot early signs of trouble and provide professional cleanings. Schedule exams every six months, or more frequently if you have chronic conditions, dry mouth, or a history of oral pathology. Professional scaling removes calculus and deeply embedded pigments that home care cannot address, while oral cancer screenings ensure early detection of potentially serious mucosal changes.

Conclusion

Noticing an orange tongue can be alarming, but it is usually a harmless condition caused by dietary stains or a temporary buildup of bacteria. By practicing good oral hygiene, staying hydrated, and paying attention to what you consume, you can often resolve the issue on your own. The oral cavity is a highly responsive environment, and tongue discoloration serves as a visible indicator of ecological shifts, lifestyle factors, or physiological stressors. Implementing consistent, evidence-based care routines allows the tongue's natural exfoliation cycle and salivary defense mechanisms to restore optimal health.

However, if the discoloration persists or is accompanied by pain or other concerning symptoms, it's important to consult a dentist or physician to rule out any underlying health problems. Your tongue can be a window into your overall health, so a quick look in the mirror each day is a simple and effective wellness check. Proactive monitoring, combined with prompt professional evaluation when abnormalities arise, ensures that minor changes do not progress into complex clinical scenarios. Maintaining oral health is intrinsically linked to cardiovascular wellness, metabolic regulation, and immune function, making daily tongue care a small but powerful component of holistic health management.

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Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice. If you have a persistent orange tongue or other concerning symptoms, consult a healthcare provider or dentist for proper evaluation and treatment.

Frequently Asked Questions

Can an orange tongue be a sign of a serious medical condition?

In the vast majority of cases, an orange tongue results from benign causes like food dyes, poor hygiene, or dry mouth. However, it can occasionally indicate more serious systemic issues, particularly when accompanied by additional symptoms. Jaundice, stemming from liver dysfunction, biliary obstruction, or hemolytic disorders, can present with a yellow-orange mucosal tint alongside scleral icterus and skin discoloration. Persistent fungal infections may signal uncontrolled diabetes or immune compromise. If the orange coating fails to resolve with basic hygiene measures, is accompanied by pain, fever, difficulty swallowing, or unexplained weight loss, seeking medical evaluation is essential to rule out underlying pathology.

How long does it take for an orange tongue to go away?

The timeline for resolution depends entirely on the underlying cause. Dietary staining and mild debris accumulation typically clear within 24 to 48 hours after implementing thorough tongue cleaning and rinsing. If bacterial or fungal overgrowth is responsible, improvement usually occurs within 5 to 14 days of targeted treatment or enhanced oral care protocols. Medication-induced discoloration will fade gradually after discontinuation or course completion, generally taking 3 to 7 days for metabolic clearance. Chronic conditions like GERD, xerostomia, or black hairy tongue may require several weeks of consistent lifestyle modification and medical management before the tongue returns to a normal appearance.

Is it safe to scrape an orange tongue every day?

Yes, daily tongue scraping is not only safe but highly recommended by dental professionals for maintaining oral health. When performed correctly using a dedicated tongue scraper or a soft-bristled toothbrush, the process removes accumulated biofilm, dead cells, and trapped food particles without damaging the delicate mucosal tissue. It is important to use gentle, consistent pressure and avoid aggressive back-and-forth scrubbing, which can cause microtears, increase inflammation, or trigger the gag reflex. Cleaning the tongue should be incorporated into a twice-daily oral hygiene routine, preferably before brushing teeth to maximize the removal of odor-causing compounds and pigment-retentive debris.

Can dehydration cause my tongue to look orange?

Absolutely. Dehydration significantly reduces salivary flow, compromising the mouth's natural cleansing and antimicrobial functions. When saliva becomes thick and scant, the tongue's papillae dry out and fail to shed normally, creating a rougher surface that traps dead cells, bacteria, and food residues. This concentrated environment accelerates pigment formation and staining. Mild dehydration can cause a dry, sticky sensation and a faint yellowish-orange film, while severe or chronic fluid deficit leads to a thicker, more pronounced coating. Rehydrating through consistent water intake, avoiding excessive caffeine or alcohol, and using saliva stimulants like xylitol gum typically reverses dehydration-related tongue discoloration within a few days.

What oral hygiene products work best for removing tongue discoloration?

The most effective approach combines mechanical cleaning with targeted antimicrobial support. A high-quality stainless steel or copper tongue scraper efficiently removes biofilm and debris. Pair this with a gentle, alcohol-free mouthwash containing essential oils (like eucalyptol, menthol, thymol) or cetylpyridinium chloride, which reduces bacterial load without causing mucosal irritation or drying the tissue. Chlorhexidine gluconate (0.12%) can be used short-term under dental supervision for stubborn bacterial overgrowth. Baking soda rinses (½ teaspoon dissolved in warm water) help neutralize acidic environments that favor pigment-producing microbes. Avoid products with harsh alcohols, strong astringents, or excessive flavoring agents, as they can disrupt the oral microbiome and exacerbate discoloration by triggering compensatory dryness.