I'm debating whether to buy the full article because the assertion that "Carotenoids include nutrients like vitamin A, beta-carotene and lutein" (a line included in the news stories but not in the journal abstract) may be misleading in the context of the study.
It is true that lutein is a carotenoid, but lutein--like several other carotenoids, including zeaxanthin, astaxanthin and lycopene--is not converted to retinol. If vitamin A is the problem, then non-vitamin A carotenoids should not be a problem.
I would really like to know which carotenoids they evaluated. I just need to decide if I want to know $35 worth.
Edited to add: Okay, now I want a differential study to distinguish between those carotenoids that convert to retinol and those that don't:
http://foodforbreastcancer.com/studies/7389
"The women completed a mailed questionnaire at baseline which collected data concerning the frequency of antioxidant supplement use since diagnosis (multivitamins with or without minerals, vitamin C, vitamin E, beta-carotene, lycopene, combination multiple carotenoids (vitamin A, alpha-carotene, beta-cryptoxanthin, beta-carotene, lutein, lycopene, zeaxanthin), selenium, zinc, coenzyme Q10, and soy), as well as factors known to influence breast cancer risk."
Of course, with all the googling, I found other studies to indicate lutein may contribute to the development of lung cancer. Lycopene, on the other hand, has been demonstrated to suppress prostate cancer.
The one supplement I really want to take--astaxanthin--seems not to have been studied in this context at all.
My aching head...