The Role of Carotenoids in the Fight Against Oxidative Stress and Age-Related Diseases

By Donna Wright

Edited and approved by Stephen Rose, PhD

Carotenoids are natural pigments made by plants, algae, and certain bacteria. They are responsible for many of the red, orange, and yellow colors seen in foods, and more than 600 carotenoids have been identified. In human nutrition, carotenoids matter partly because some act as antioxidants and some can serve as precursors to vitamin A.[1,2]

Two major carotenoid groups are especially important in the diet: carotenes and xanthophylls. Carotenes, such as beta-carotene and lycopene, do not contain oxygen. Xanthophylls, such as lutein and zeaxanthin, do. Not every carotenoid has vitamin A activity, but several provitamin A carotenoids—including beta-carotene, alpha-carotene, and beta-cryptoxanthin—can contribute to vitamin A status.[1,3]

In practical terms, carotenoid-rich foods include carrots, sweet potatoes, pumpkin, tomatoes, leafy greens, yellow corn, peppers, egg yolks, and some fruits. The exact carotenoid profile varies by food. Leafy greens may look dominated by chlorophyll, but they still supply carotenoids, especially lutein and zeaxanthin.[1,3]

Why carotenoids matter in aging

Carotenoids are often discussed in the context of oxidative stress, a process that has been implicated in aging and in many age-related diseases. That does not mean carotenoids are a cure for aging. It means they are one part of a broader dietary pattern that may help limit oxidative damage and inflammation over time.[2]

Eye health: the strongest case

The clearest evidence for carotenoids in age-related health involves the eye. Lutein and zeaxanthin are the major carotenoids concentrated in the macula, where they help filter short-wavelength blue light and support antioxidant defense in retinal tissue.[4]

That biological role is supported by human clinical evidence. In the long-term AREDS2 follow-up, lutein and zeaxanthin were associated with a lower risk of progression to late age-related macular degeneration when compared with beta-carotene, and beta-carotene was linked to a higher lung-cancer risk in participants with a smoking history.[5] That does not mean carotenoids guarantee perfect vision or prevent all eye disease, but it does make lutein- and zeaxanthin-rich foods a sensible part of an eye-healthy diet.[4,5]

Cardiovascular health

A 2024 systematic review concluded that higher serum carotenoid levels are associated with lower cardiovascular risk factors and inflammatory markers, and that carotenoid-rich foods may be more useful than supplementation. At the same time, the review also noted that the effects of individual carotenoids on cardiovascular risk remain uncertain.[6]

Carotenoid-rich foods may support cardiometabolic health as part of a healthy diet. However, it is not reasonable to claim that carotenoids reliably “clear arteries,” treat high cholesterol, or prevent cardiovascular disease on their own.[6]

Cancer risk: food first, supplements with caution

Current umbrella-level evidence suggests that higher dietary intake and higher blood concentrations of carotenoids are associated with a lower risk of some cancers.[7]

It is also important to separate foods from supplements. In the same umbrella meta-analysis, high-dose carotenoid supplements—especially beta-carotene—were associated with increased risk of total cancer, lung cancer, and bladder cancer in some settings.[7] That concern is especially relevant for smokers and people with substantial asbestos exposure: in the CARET follow-up, beta-carotene plus retinyl palmitate was associated with increased lung-cancer incidence and higher all-cause mortality in high-risk participants.[8]

Carotenoid-rich foods fit well into a cancer-prevention diet, but high-dose beta-carotene supplementation is not a safe shortcut, especially for smokers.[7,8]

Immune function and vitamin A

Some carotenoids matter because they contribute to vitamin A intake, and vitamin A is essential for vision, epithelial integrity, growth, and immune function.[3] Carotenoids have also been studied for immunomodulatory and anti-inflammatory effects, but the human intervention evidence is still mixed and incomplete.[9]

That makes it fair to say carotenoid-rich diets can support normal physiology, including aspects of immune health.[3,9]

Should you rely on supplements?

Food should come first. Whole foods that contain carotenoids also bring fiber, minerals, and other phytochemicals that supplements do not fully replicate. Current reviews generally support increased intake of carotenoid-rich foods more strongly than routine supplementation for disease prevention.[6,7]

There are also safety nuances. Very high intake of beta-carotene-rich foods can lead to carotenodermia, a yellow-orange skin discoloration due to carotene deposition. It is usually harmless and reversible, but it shows that even food-based intake is not literally consequence-free.[10] Supplement use also deserves caution, particularly when products contain high doses of beta-carotene or preformed vitamin A.[7,8,10]

The bottom line

Carotenoids are not magic compounds, but they are biologically important and worth paying attention to. The strongest evidence supports a role for lutein and zeaxanthin in macular health, while broader evidence suggests that diets rich in carotenoid-containing foods may support healthy aging, cardiometabolic health, and lower risk of some chronic diseases.[2,4–7]

The safest and most defensible advice is simple: eat a varied diet rich in colorful fruits and vegetables, do not rely on supplements as a shortcut, and be especially cautious with beta-carotene supplements if you smoke or used to smoke.[6–8]

References

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Bakac, E.R.; Percin, E.; Gunes-Bayir, A.; Dadak, A. A Narrative Review: The Effect and Importance of Carotenoids on Aging and Aging-Related Diseases. Int. J. Mol. Sci. 2023, 24, 15199.

Olmedilla-Alonso, B.; Rodríguez-Rodríguez, E.; Beltrán-de-Miguel, B.; Estévez-Santiago, R. Dietary β-Cryptoxanthin and α-Carotene Have Greater Apparent Bioavailability Than β-Carotene in Subjects from Countries with Different Dietary Patterns. Nutrients 2020, 12, 2639.

Li, X.; Holt, R.R.; Hackman, R.M. Potential Roles of Dietary Zeaxanthin and Lutein in Macular Health and Function. Nutr. Rev. 2023, 81, 670–683.

Chew, E.Y.; Clemons, T.E.; Agrón, E.; Domalpally, A.; Keenan, T.D.L.; Vitale, S.; Weber, C.; Smith, D.C.; AREDS2 Research Group. Long-term Outcomes of Adding Lutein/Zeaxanthin and ω-3 Fatty Acids to the AREDS Supplements on Age-Related Macular Degeneration Progression: AREDS2 Report 28. JAMA Ophthalmol. 2022, 140, 692–698.

Sumalla-Cano, S.; Eguren-García, I.; Lasarte-García, Á.; Prola, T.A.; Martínez-Díaz, R.; Elío, I. Carotenoids Intake and Cardiovascular Prevention: A Systematic Review. Nutrients 2024, 16, 3859.

Sui, J.; Guo, R.; Li, Z.; Zhang, L.; Zhou, Y.; Chen, Y.; et al. The Efficacy of Dietary Intake, Supplementation, and Blood Concentrations of Carotenoids in Cancer Prevention: Insights from an Umbrella Meta-Analysis. Foods 2024, 13, 1321.

Goodman, G.E.; Thornquist, M.D.; Balmes, J.; Cullen, M.R.; Meyskens, F.L.; Omenn, G.S.; et al. The Beta-Carotene and Retinol Efficacy Trial: Incidence of Lung Cancer and Cardiovascular Disease Mortality During 6-Year Follow-up After Stopping β-Carotene and Retinol Supplements. J. Natl. Cancer Inst. 2004, 96, 1743–1750.

Medina-García, M.; Baeza-Morales, A.; Pascual-González, S.; Pérez-Sánchez, C.; Soler-Oliva, J.M. Carotenoids and Their Interaction with the Immune System. Antioxidants 2025, 14, 1111.

Kapsetaki, M.E. Diet-Induced Carotenodermia: A Literature Review. Int. J. Dermatol. 2024, 63, 161–168.