The Primary Cause: Excessive Dietary Intake
The most common reason for carotenemia is consuming too many foods rich in carotene. Carotenoids are pigments found in many fruits and vegetables. When eaten in large amounts for a long time, these fat-soluble compounds build up in the bloodstream and deposit in the skin's outer layer, causing a yellow-orange color. This is most visible on the palms, soles, and face. Reducing intake of these foods will gradually restore normal skin color.
High-Carotene Foods
Foods commonly linked to carotenemia include carrots, sweet potatoes, pumpkin, winter squash, and dark, leafy greens like spinach and kale. Orange fruits such as cantaloupe, apricots, papaya, and mangoes are also high in beta-carotene. Other sources can include certain nutritional supplements and red palm oil.
Who is Most Susceptible?
Infants and young children, often due to consuming pureed carrots or sweet potatoes, are frequently affected. Vegetarians, vegans, and individuals on restrictive diets focusing on high-carotene foods may also be more prone to this condition.
Secondary Causes: Underlying Medical Conditions
Carotenemia can also arise from medical conditions that disrupt the body's processing of carotene, even with a normal diet.
Metabolic and Systemic Diseases
Conditions that can interfere with the conversion of carotene to vitamin A or affect lipid levels include hypothyroidism, diabetes mellitus, and anorexia nervosa. Liver and kidney diseases, along with rare inborn errors of metabolism, can also contribute to carotene accumulation.
Carotenemia vs. Jaundice
It's important to distinguish carotenemia from jaundice. A key difference is that carotenemia does not cause yellowing of the whites of the eyes (sclera), while jaundice does.
| Feature | Carotenemia | Jaundice |
|---|---|---|
| Skin Color | Yellow-orange pigmentation | Yellowish pigmentation |
| Location | Concentrated on palms, soles, and face | Widespread pigmentation |
| Sclera (Whites of Eyes) | Spared, remains white | Yellowing of the sclera |
| Cause | Excessive carotene intake or metabolic issue | High bilirubin levels due to liver or bile duct issues |
| Health Impact | Benign and harmless | Can indicate a serious underlying disease |
How Carotene Affects the Skin
Carotenoids are absorbed into the skin's outer layer, the stratum corneum, when blood levels are high. This accumulation of pigment causes the characteristic color. The body regulates the conversion of carotene to vitamin A, which is why excessive carotene intake typically doesn't lead to vitamin A toxicity.
Resolution of Carotenemia
Diet-induced carotenemia resolves by reducing the intake of high-carotene foods. The color fades over several weeks or months as the carotene is processed. For secondary carotenemia, treating the underlying medical condition is necessary. The condition is reversible and benign. More details can be found on the NCBI website.
Conclusion
Carotenemia primarily results from eating too many carotene-rich foods, but can also be caused by conditions affecting carotene metabolism like hypothyroidism or diabetes. It's a harmless condition distinct from jaundice, particularly because the whites of the eyes remain unaffected. Dietary changes or addressing the underlying medical cause typically resolves the skin discoloration.
