Avoid in individuals with a known allergy or hypersensitivity to lutein.

In general, lutein seems fairly safe. Purified crystalline lutein is generally recognized as safe (GRAS) based on animal toxicity studies.

Nevertheless, use cautiously in people at risk for cardiovascular disease due to the possibility of increasing cardiovascular disease risk in those with higher plasma lutein levels. Also, use cautiously in patients at risk for cancer due to the possibility of an increased cancer risk in those with higher plasma lutein levels.

Avoid in patients hypersensitive to lutein or zeaxanthin.

Due to the lack of available human studies, supplementation with lutein is not recommended in pregnant or breastfeeding women.

Lutein is likely safe when used at doses of up to 20 milligrams daily for up to nine weeks, or 15 milligrams three times weekly for up to two years. Purified crystalline lutein is generally recognized as safe (GRAS) based on animal toxicity studies.

Although there is no proven effective dose for lutein, lutein is commercially available in various doses. For instance, the manufacturer Twinlab (Ronkonkoma, NY) makes a 6 milligram or 20 milligram lutein preparation. Lutein 12-15 milligrams been taken by mouth for up to two years as an antioxidant and to treat cataracts. Lutein 10-40 milligrams daily has been used for six to 12 months in the treatment of eye disorders.

There is no proven safe or effective dose for lutein in children.

In humans, moderate consumption of various types of alcoholic beverages (red wine, beer, and spirits) may decrease plasma lutein/zeaxanthin.

Although not well studied in humans, lutein may alter blood sugar levels. Caution is advised in patients taking drugs for diabetes by mouth or insulin. Blood sugar levels should be monitored closely by a qualified healthcare professional, including a pharmacist. Medication adjustments may be necessary.

Although not well studied in humans, lutein may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs and their intended effects may be altered. Patients taking any medications should check the package insert and speak with a qualified healthcare professional, including a pharmacist, about possible interactions.

Cholesterol-altering medications, antioxidants, anti-cancer agents, cholestyramine, colestipol, mineral oil, nicotine, orlistat, and retinol all may alter lutein levels in the body. However, the effects of supplementation with lutein and these agents are unknown.

Alpha-tocopherol (vitamin E), antioxidants, anti-cancer agents, beta-carotene, cholesterol-altering herbs, carotenoids, mineral oil, retinol, and zeaxanthin all may alter lutein levels in the body. However, the effects of supplementation with lutein combined with these agents are unknown.

Lutein may interfere with the way the body processes certain herbs or supplements using the liver's "cytochrome P450" enzyme system. As a result, the levels of other herbs or supplements may become too high in the blood.

Dietary fiber may decrease the theoretical antioxidative effects of lutein supplements. Furthermore, the proposed antioxidant activity of lutein has the potential to inhibit fatty acid oxidation and increase levels of polyunsaturated fatty acids from supplements. Caution is advised due to possible additive effects.

Although not well studied in humans, lutein may alter blood glucose levels. Caution is advised when using herbs or supplements that may also alter blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.