A carotenoid substance called zeaxanthin, when ingested orally at suitable dosages such as 30 to 100 mg/day for a span of 1 to 2 weeks, can provide effective protection against sunburns, and can give skin a darker tint that emulates a healthy suntan. In tests involving adults, it was found that zeaxanthin dosages of 30 to about 80 mg per day were sufficient to induce: (i) a mild but noticeable tinting, shading, or darkening of skin color, comparable to a mild suntan； (ii) a substantial increase in the person's ability to withstand elevated levels of sun or UV exposure； and, (iii) an increased ability of reddened and sunburned skin to convert into intact skin that looks browned and healthily tanned. Oral ingestion of dosages of zeaxanthin after a noticeable darkening of the skin has been achieved further enhances a tanned appearance and/or protects against sun damage.
