Because people with scleroderma, a connective-tissue disorder characterized by hardened skin, have low levels of beta-carotene in their blood, some researchers speculate that beta-carotene supplements may be beneficial for those with the condition. Due to methodological flaws in the studies that have been conducted to date, however, research has not confirmed this theory. At this time, it is best to obtain beta-carotene from dietary sources and avoid supplementation until more information is available.
The richest sources of beta-carotene are yellow, orange, and green leafy fruits and vegetables (such as carrots, spinach, lettuce, tomatoes, sweet potatoes, broccoli, cantaloupe, and winter squash). In general, the greater the intensity of the color of the fruit or vegetable, the more beta-carotene it contains.