From the Guidelines
Carotenemia is not directly related to vitamin A levels but rather occurs due to excessive consumption of carotene-rich foods. Carotenemia is a benign condition characterized by yellowish discoloration of the skin, particularly on the palms, soles, and face, caused by high blood levels of carotene. While beta-carotene is a precursor to vitamin A, the body regulates the conversion of carotene to vitamin A, so carotenemia does not typically cause vitamin A toxicity or deficiency 1. The condition is harmless and resolves when carotene intake is reduced. Common sources of carotene include carrots, sweet potatoes, squash, and leafy green vegetables. Unlike jaundice, the yellowing in carotenemia does not affect the sclera (whites of the eyes). No specific treatment is needed beyond dietary modification, and the skin discoloration gradually fades over weeks to months after reducing carotene intake.
Some key points to consider:
- The recommended dietary allowance (RDA) for vitamin A is 700 µg/day for women and 900 µg/day for men, with a tolerable upper intake level of 3,000 µg/day 1.
- Excessive intake of carotene-rich foods can lead to carotenemia, but this is not typically related to vitamin A toxicity or deficiency.
- Carotenemia is a benign condition that resolves with dietary modification, and no specific treatment is needed beyond reducing carotene intake.
- It is essential to distinguish carotenemia from jaundice, as the latter can be a sign of a more serious underlying condition.
In terms of morbidity, mortality, and quality of life, reducing carotene intake is the most effective way to manage carotenemia, as it can help to alleviate the yellowish discoloration of the skin and improve overall quality of life. Additionally, a balanced diet that meets the recommended daily intake of vitamin A and other essential nutrients can help to prevent carotenemia and other nutrition-related disorders 1.
From the Research
Carotenemia and Vitamin A Levels
- Carotenemia is characterized by an abnormal yellowish orange pigmentation of the skin, most prominently seen on the palms and soles 2.
- It is caused by excessive intake of carotene-rich food such as oranges and carrots in most cases 2, 3.
- Pro-vitamin A carotenoids, such as beta-carotene, serve as precursors of vitamin A 4, 5.
- The conversion of beta-carotene to vitamin A is slow, and vitamin A poisoning does not occur despite massive doses of carotene 3.
- Carotenemia can be associated with several diseases, including hypothyroidism, diabetes mellitus, and anorexia nervosa, but these conditions do not cause carotenemia directly 2, 4, 3.
- In hypothyroidism, the beta-carotene serum level is significantly higher, while in hyperthyroidism, it is lower 6.
- The relationship between carotenoid intake and hypercarotenaemia is not fully understood, and some studies suggest that genetic factors may play a role in the development of hypercarotenaemia 4.
Vitamin A and Carotenemia
- Vitamin A levels are not significantly different in hyperthyroid, hypothyroid, and euthyroid patients, despite changes in beta-carotene levels 6.
- A vitamin A and protein-rich food seems to rule out any vitamin A deficiency in hyperthyroidism and hypothyroidism 6.
- The conversion of beta-carotene to vitamin A is accelerated by thyroxine and hyperthyroidism, respectively 6.