Dietary betacarotene and lung cancer risk in U.S. non-smokers Mayne ST; Janerich DT; Greenwald P; Chorost S; Tucci C; Zaman MB; Melamed MR; Kiely M; McKneally MF, J Natl Cancer Inst., Jan 5 1994, 86(1)p33-8
The study suggested that beta carotene supplements reduce the risk of lung cancer in nonsmoking men and women.
Emerging role of beta-carotene and antioxidant nutrients in prevention of oral cancer Garewal HS; Schantz S
Arch Otolaryngol Head Neck Surg Feb 1995,121(2),p141-4
This study showed that beta-carotene produces regression of oral leukoplakia and plays a significant role in preventing oral cancer.
A preliminary trial of beta-carotene in subjects infected with the human immunodeficiency virus (HIV) Garewal H.S.; Ampel N.M.; Watson R.R.; Prabhala R.H.; Dols C.L. J. Nutr., 1992,122/3 SUPPL. (728-732)
There were eleven patients with HIV included in the study. Each subject received 60mg (100,000IU) of beta-carotene daily for four months. No toxicity was observed in the study, which showed an increased number of natural killer cells, which help defend the body.
Carotenoids and the Immune Response Bendich,A. Journal of Nutrition, 1989; 119;112-115.
The study showed that beta-carotene enhanced the activity of T cells and B cells, and boosted the tumor-destroying ability of macrophages, natural-killer cells, and cytotoxic T cells.
Serum carotenoids and coronary heart disease: The lipid research clinic’s coronary primary prevention trial follow-up study (LRC-CPPT) Morris D.L.; Kritchevsky S.B.; Davis C.E. JAMA, 1994, 272/18 (1439-1441)
The LRC-CPPT participants with higher serum carotenoid levels had a decreased risk of incident CHD, with the finding stronger among men who had never smoked.
Inhibitory effect of conjugated dienoic derivatives of linoleic acid and beta-carotene on the in vitro growth of human cancer cells Shultz TD; Chew BP;Seaman WR; Luedecke LO
Cancer Lett (NETHERLANDS) Apr 15 1992, 63(2)p125-33
Beta-carotene demonstrated an inhibitory effect on breast cancer cells (MCF-7)
Natural killer cell activity in elderly men is enhanced by beta-carotene supplementation American Journal of Clinical Nutrition (USA), 1996,64/5 (772-777)
This study showed that long-term beta-carotene supplementation enhanced natural killer (NK) cell activity in elderly men, which may be beneficial for viral and tumoral surveillance.
Dietary carotenoids and risk of coronary artery disease (CAD) in women Osganian SK, Stampfer MJ, Rimm E, et al
American Journal of Clinical Nutrition, 2003;77:1390-1399
Women with the highest dietary intake of beta-carotene and alpha-carotene were least likely to have fatal or nonfatal heart attacks. Those with the highest intake of beta-carotene were 26% less likely to have CAD than those with the lowest intake and those with the highest intake of alpha-carotene were 20% less likely to experience CAD.
Potent preventive action of alpha-carotene against carcinogenesis and the promoting stage of lung and skin carcinogenesis in mice are suppressed more effectively by alpha-carotene than by beta-carotene. Cancer Research 52: 6583-6587 December 1,1992
The mean number of hepatomas per mouse was significantly decreased by alpha-carotene supplementation as compared with that in the control group. On the other hand, beta-carotene at the same dose did not show any such significant difference from the control group.
Alpha-carotene, but not beta-carotene, reduced the number of lung tumors per mouse to about 30% of that in the control group.
Alpha-carotene was also found to have a stronger effect than beta-carotene in suppressing the promoting activity of 12-O-tetradecanoylphorbol-13-acetate on skin carcinogenesis in 7, 12-dimethylbenz(a) anthracene-initiated mice.
Intake of specific carotenoids and risk of lung cancer in 2 prospective US reports Michaud DS et al. American Journal of Clinical Nutrition 72(4):990-7 Oct 2000
Alpha-carotene and lycopene were significantly associated with a lower risk of lung cancer. Intake of beta-carotene, lutein, and beta-cryptoxanthin were also associated with a lower risk of lung cancer but the relationships were not statistically significant.
Beta-carotene prolongs survival, decreases lipid peroxidation and enhances glutathione status in transplantable murine lymphoma Basu M et al. Phytomedicine 7(2):151-9. Apr 2000
The authors concluded that the prolonged survival observed in beta-carotene supplemented animals may be attributed to the higher resistance offered by animals receiving beta-carotene towards lipid peroxidation-related tissue injury.