fect of β-carotene in smokers are somewhat conflicting. The results of ongoing studies may help resolve this issue. There also appears to be a relationship between the adverse effects of β-carotene and both smoking and alcohol consumption in the ATBC and CARET trials. In the ATBC trial, only those men who consumed more than 11 g/day of alcohol (approximately one drink per day) showed an adverse response to β-carotene supplementation (Albanes et al., 1996). In the CARET study, adverse effects were associated with the individuals in the highest quartile of alcohol intake (Omenn et al., 1996a).

Carotenodermia. Carotenodermia is characterized by yellowish discoloration of the skin that results from an elevation of plasma carotene concentrations. This condition has been reported in adults taking supplements containing 30 mg/day or more of β-carotene for long periods of time or consuming high levels of carotenoid-rich foods such as carrots (Bendich, 1988) and is the primary effect of excess carotenoid intake noted in infants, toddlers, and young children (Lascari, 1981). Carotenodermia is distinguished from jaundice in that the ocular sclera are yellowed in jaundiced subjects but not in those with carotenodermia. Carotenodermia is considered harmless and is readily reversible when carotene ingestion is discontinued.

Lycopenodermia. Lycopenodermia results from high intakes of lycopene-rich foods such as tomatoes and is characterized by a deep orange discoloration of the skin. Lycopene is a more intensely colored pigment than carotene and may cause discoloration at lower concentrations than other carotenoids (Lascari, 1981).

Other Adverse Effects. Allergic reactions, increased incidence of prostate cancer, retinopathy, leukopenia, and reproductive disorders have been associated anecdotally with high carotene consumption (Bendich, 1988; Kobza et al., 1973; Shoenfeld et al., 1982). None of these effects has been confirmed by clinical trials. There is no evidence of hypervitaminosis A in individuals consuming high levels of β-carotene or other carotenoids (up to 180 mg/day) (Lewis, 1972; Mathews-Roth, 1986; Mathews-Roth et al., 1972, 1974).

Dose-Response Assessment

The data on the potential for β-carotene to produce increased lung cancer rates in smokers are conflicting and not sufficient for a

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