TY - JOUR
T1 - Citrus peel use is associated with reduced risk of squamous cell carcinoma of the skin
AU - Hakim, I. A.
AU - Harris, R. B.
AU - Ritenbaugh, C.
N1 - Funding Information:
This publication was made possible by National Cancer Institute Grant P01 CA-27502. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Cancer Institute. Address correspondence to Iman Hakim, M.D., Ph.D., M.P.H., Arizona Cancer Center, College of Medicine, 1515 N. Campbell Ave., PO Box 245024, Tucson, AZ 85724. Phone: (520) 626-5355. FAX: (520) 626-5348. E-mail: [email protected].
Funding Information:
The authors thank Dr. David Alberts (Div. of Cancer Prevention and Control) for support, Steve Rodney for assistance with data management, and Mary Lurie for assistance with interviewing and data entry. This research was supported by National Cancer Institute Grant K07 CA-76008.
PY - 2000
Y1 - 2000
N2 - Limonene has demonstrated efficacy in preclinical models of breast and colon cancers. The principal sources of d-limonene are the oils of orange, grapefruit, and lemon. The present case-control study was designed to determine the usual citrus consumption patterns of an older Southwestern population and to then evaluate how this citrus consumption varied with history of squamous cell carcinoma (SCC) of the skin. In this Arizona population, 64.3% and 74.5% of the respondents reported weekly consumption of citrus fruits and citrus juices, respectively. Orange juice (78.5%), orange (74.3%), and grapefruit (65.3%) were the predominant varieties of citrus consumed. Peel consumption was not uncommon, with 34.7% of all subjects reporting citrus peel use. We found no association between the overall consumption of citrus fruits [odds ratio (OR) = 0.99, 95% confidence interval (CI) = 0.73-1.32] or citrus juices (OR = 0.97, 95% CI = 0.71-1.31) and skin SCC. However, the most striking feature was the protection purported by citrus peel consumption (OR = 0.66, 95% CI = 0.45-0.95). Moreover, there was a dose-response relationship between higher citrus peel in the diet and degree of risk lowering. This is the first study to explore the relationship between citrus peel consumption and human cancers. Our results show that peel consumption, the major source of dietary d-limonene, is not uncommon and may have a potential protective effect in relation to skin SCC. Further studies with large sample sizes are needed to more completely evaluate the interrelationships between peel intake, bioavailability of d-limonene, and other lifestyle factors.
AB - Limonene has demonstrated efficacy in preclinical models of breast and colon cancers. The principal sources of d-limonene are the oils of orange, grapefruit, and lemon. The present case-control study was designed to determine the usual citrus consumption patterns of an older Southwestern population and to then evaluate how this citrus consumption varied with history of squamous cell carcinoma (SCC) of the skin. In this Arizona population, 64.3% and 74.5% of the respondents reported weekly consumption of citrus fruits and citrus juices, respectively. Orange juice (78.5%), orange (74.3%), and grapefruit (65.3%) were the predominant varieties of citrus consumed. Peel consumption was not uncommon, with 34.7% of all subjects reporting citrus peel use. We found no association between the overall consumption of citrus fruits [odds ratio (OR) = 0.99, 95% confidence interval (CI) = 0.73-1.32] or citrus juices (OR = 0.97, 95% CI = 0.71-1.31) and skin SCC. However, the most striking feature was the protection purported by citrus peel consumption (OR = 0.66, 95% CI = 0.45-0.95). Moreover, there was a dose-response relationship between higher citrus peel in the diet and degree of risk lowering. This is the first study to explore the relationship between citrus peel consumption and human cancers. Our results show that peel consumption, the major source of dietary d-limonene, is not uncommon and may have a potential protective effect in relation to skin SCC. Further studies with large sample sizes are needed to more completely evaluate the interrelationships between peel intake, bioavailability of d-limonene, and other lifestyle factors.
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U2 - 10.1207/S15327914NC372_7
DO - 10.1207/S15327914NC372_7
M3 - Article
C2 - 11142088
AN - SCOPUS:0033637602
SN - 0163-5581
VL - 37
SP - 161
EP - 168
JO - Nutrition and cancer
JF - Nutrition and cancer
IS - 2
ER -