人类是唯一的无差别类胡萝卜素积累者，所以人体积累了不同类型和浓度不同的膳食类胡萝卜素。过去，由于类胡萝卜素可以抑制单一分子氧(1O2)而被认为是生理抗氧化剂。在20世纪90年代，大规模干预研究未能证明补充β-胡萝卜素摄入量减少肺癌发病率，尽管其抗氧化活性被认为有助于预防氧化应激诱导的癌变。然而，随着1O2的病理生理作用的出现，以及膳食类胡萝卜素诱导抗氧化酶的能力被揭示出来，类胡萝卜素的抗氧化活性又引起了新的关注。本综述聚焦于来自水果和蔬菜的六种主要类胡萝卜素，并从促进健康和预防疾病的角度重新考察它们作为生物抗氧化剂的生理功能。β-胡萝卜素9'，10'-氧化酶衍生物通过促进抗氧化酶活性的增加来触发作用。叶黄素和玉米黄素在人类黄斑细胞中选择性积累，以充当抗氧化剂，保护免受光引起的黄斑损伤。番茄红素专属且浓度较高地积累在睾丸中，其抗氧化活性可能有助于消除氧化损伤。膳食类胡萝卜素在皮肤受光照后，在皮肤中持久沉积后展现出其抗氧化活性。应该确定适当的膳食类胡萝卜素摄入水平以预防疾病，因为如果过度积累，它们可能会产生有害的过氧化物作用。最后，预计很快将会理解人类为何是无差别类胡萝卜素积累者的原因。

Humans are unique indiscriminate carotenoid accumulators, so the human body accumulates a wide range of dietary carotenoids of different types and to varying concentrations. Carotenoids were once recognized as physiological antioxidants because of their ability to quench singlet molecular oxygen (1O2). In the 1990s, large-scale intervention studies failed to demonstrate that supplementary β-carotene intake reduces the incidence of lung cancer, although its antioxidant activity was supposed to contribute to the prevention of oxidative stress-induced carcinogenesis. Nevertheless, the antioxidant activity of carotenoids has attracted renewed attention as the pathophysiological role of 1O2 has emerged, and as the ability of dietary carotenoids to induce antioxidant enzymes has been revealed. This review focuses on six major carotenoids from fruit and vegetables and revisits their physiological functions as biological antioxidants from the standpoint of health promotion and disease prevention. β-Carotene 9',10'-oxygenase-derived oxidative metabolites trigger increases in the activities of antioxidant enzymes. Lutein and zeaxanthin selectively accumulate in human macular cells to protect against light-induced macular impairment by acting as antioxidants. Lycopene accumulates exclusively and to high concentrations in the testis, where its antioxidant activity may help to eliminate oxidative damage. Dietary carotenoids appear to exert their antioxidant activity in photo-irradiated skin after their persistent deposition in the skin. An acceptable level of dietary carotenoids for disease prevention should be established because they can have deleterious effects as prooxidants if they accumulate to excess levels. Finally, it is expected that the reason why humans are indiscriminate carotenoid accumulators will be understood soon.