What is Carotenemia?
Carotenemia is the medical term for the yellow-orange pigmentation of the skin (carotenoderma) that occurs from consuming an excessive amount of carotene over a prolonged period. This condition is most noticeable on areas of the body where the skin is thickest, such as the palms of the hands and soles of the feet, and around the nose. A key way to differentiate carotenemia from other conditions like jaundice is that the whites of the eyes (sclera) remain unaffected and white.
The primary cause is the consumption of foods and supplements rich in beta-carotene. The body converts beta-carotene, a provitamin, into active vitamin A. When the body has sufficient vitamin A, the conversion process slows, and excess beta-carotene accumulates in the bloodstream and is deposited in the outer skin layer and fat tissue, leading to carotenemia. Carotenemia is benign and resolves when high carotene intake is reduced.
Common Sources of Excess Carotene
Excess carotene intake comes mainly from food and supplements.
Dietary Sources of Carotenoids
Many colorful fruits and vegetables contain carotenoids and are common causes of carotenemia when consumed in large amounts.
- Orange and yellow vegetables like carrots, sweet potatoes, pumpkins, and squash.
- Leafy greens such as spinach and kale.
- Orange and yellow fruits like apricots, cantaloupe, and mangoes.
- Other sources include butter and eggs.
Supplemental Sources
While food sources are generally safe beyond skin discoloration, high-dose beta-carotene supplements carry risks. Studies have shown that high-dose beta-carotene supplementation increased the risk of lung cancer in smokers and those with asbestos exposure. Therefore, many health authorities recommend against using these supplements.
Carotenemia vs. Hypervitaminosis A
It is important to distinguish carotenemia from hypervitaminosis A (vitamin A toxicity), which is a serious health risk. Hypervitaminosis A is caused by excessive intake of preformed vitamin A, often from supplements or liver, and can have severe consequences.
Comparison Table: Carotenemia vs. Hypervitaminosis A
| Feature | Carotenemia | Hypervitaminosis A (Vitamin A Toxicity) |
|---|---|---|
| Cause | Excessive intake of provitamin A carotenoids (e.g., beta-carotene) | Excessive intake of preformed vitamin A (retinol) from supplements or animal sources |
| Toxicity | Generally considered harmless and nontoxic | Can be highly toxic and dangerous in both acute and chronic forms |
| Primary Symptom | Yellow-orange skin pigmentation (carotenoderma) | Severe headaches, blurred vision, dizziness, nausea, hair loss, liver damage, bone pain |
| Eyes | Sclera (whites of the eyes) are spared | Can cause changes in vision and papilledema |
| Resolution | Reversible by reducing carotene intake | Reverses upon stopping intake, but severe cases can cause permanent damage |
| High-Risk Group | Infants, young children, and those with high dietary intake | Individuals taking high-dose supplements or with liver disease |
How to Manage and Reverse Carotenemia
Managing diet-induced carotenemia involves adjusting dietary habits. Since the condition is harmless, medical treatment is usually unnecessary beyond reassurance.
Reducing the intake of carotene-rich foods and supplements allows the body to use or excrete stored carotenoids, causing the skin color to gradually fade over several weeks to months. A balanced diet with a variety of fruits and vegetables is recommended.
Individuals who smoke or have a history of asbestos exposure should avoid high-dose beta-carotene supplements due to increased health risks.
Other Considerations and Associated Conditions
While dietary carotenemia is benign, elevated carotene levels can occasionally indicate an underlying medical issue, known as secondary carotenemia. Certain conditions can hinder the metabolism and conversion of carotene to vitamin A, leading to its accumulation. These include hypothyroidism, diabetes mellitus, kidney or liver disease, and anorexia nervosa. Consulting a healthcare provider is necessary to address the underlying condition.
Conclusion
What does too much carotene do? It primarily leads to carotenemia, a harmless yellow-orange skin discoloration caused by excess beta-carotene intake. This is distinct from the dangerous vitamin A toxicity, which results from excessive preformed vitamin A. The body regulates beta-carotene conversion, preventing toxicity from food sources. While diet-induced carotenemia is reversible by reducing intake, high-dose beta-carotene supplements carry risks, particularly for smokers. A balanced diet is always preferable to high-dose supplements. Consult a healthcare provider with any health concerns.
For more detailed information on vitamin A and carotenoids, consult the official fact sheet from the National Institutes of Health.(https://ods.od.nih.gov/factsheets/VitaminA-HealthProfessional/)
