Q: I take a daily multivitamin as well as extra vitamin C (500 mg) and vitamin E (400 IU). Is this too much?

Also, my husband’s optometrist suggested that he take lutein to prevent macular degeneration. Is there an established RDA for lutein?

Should vitamins be taken with water or juice? Is there a difference?

A: The amount of vitamins C and E you take is well below the UL (tolerable upper intake level).

Taking more than the UL increases the risk of adverse effects.

The UL for vitamin C is 2,000 mg.

The UL for vitamin E is 1,000 mg. Expressed in IU (international units), this amount would be 1,100 IU for synthetic vitamin E and 1,500 IU for natural vitamin E.

Your multivitamin likely provides the adult RDA (recommended dietary allowance): 60 mg of vitamin C and 30 IU of vitamin E.

Vitamin C (water-soluble) and vitamin E (fat-soluble) appear to work in a complementary manner.

In fact, some research suggests a benefit for the combination in Alzheimer’s disease, atherosclerosis (plaque buildup in arteries), colorectal cancer (along with vitamin A or a multivitamin), and sunburn prevention.

Lutein: There’s not enough information to establish an RDA for lutein, a carotenoid in the beta carotene family.

Lutein is present in the macula, the central area of the retina in the eye.

Some studies suggest that a lutein-rich diet may reduce the risk of developing both age-related macular degeneration and cataracts.

Getting 6 mg of lutein daily through either diet or supplements has been proposed, although lutein in supplement form has not been studied for this purpose.

Foods high in lutein include kale (44 mg/cup), spinach (26 mg/cup), and broccoli (3 mg/cup). You’ll find substantial amounts of lutein and a similar compound called zeaxanthin in spinach, kiwi fruit, grapes, orange juice, zucchini and squash.

Lutein supplements contain 6 to 20 mg of lutein. Some of them also contain zinc, copper, vitamin C and vitamin E.

Zinc may be a key player, and lutein supplements typically contain 15 mg of this mineral. Copper is included because zinc can lead to copper deficiency.

The multivitamin you take probably provides 15 mg of zinc (as well as copper). Check the list of ingredients on the label. If so, you may not need a zinc-fortified lutein supplement.

Juice or water?: Grapefruit juice and Seville orange juice have been found to increase blood levels of some drugs, but I’m unaware of such an effect on vitamins. To avoid any possibility of an interaction, you could use plain water to wash down your medications and supplements.

© 2004, Knight Ridder/Tribune Information Services.