Estimation of Furocoumarin Intake of the U.S. Population in the National Health And Nutrition Examination Survey
Authors: Melough Melissa Moser , Kim Kijoon , Cho Eunyoung , Provatas Anthony , Perkins Christopher , Park Min Kyung , Qureshi Abrar , Chun Ock K 
Published: November 2023

Furocoumarins are a group of naturally occurring toxins in foods that possess extensive phototoxic and photogenotoxic activities. Furocoumarins can intercalate into the DNA double helix, and may form adducts upon photoactivation. This activity may underlie the reported dose‐response relationship between overall citrus consumption and skin cancer, as many citrus foods are rich sources of furocoumarins. However, little is known about typical furocoumarin intake. The few published estimates of furocoumarin intake exhibit wide variation, and these studies considered only a small number of measured food items. Therefore, the aim of this study was to use a database of 29 popular food items measured for furocoumarin content assembled by our research group to estimate furocoumarin intake in the U. S. population using a nationally representative sample from the National Health and Nutrition Examination Survey (NHANES) 2011–2012.

Measurements of furocoumarin concentrations and distributions in 29 foods and beverages were linked to consumption data reported by participants in two 24‐hour dietary recalls in the NHANES survey. Average intake of furocoumarins among U.S. adults and children was 63.2 μg/day (standard error = 9.8). Among the 2,326 adults included in this analysis, 1,721 (74%) reported consuming dietary furocoumarins (109.9 μg/day; SE = 18.5). Among the lowest quintile of consumers, mean furocoumarin intake was 0.1 μg/day (range = 0.0 to 0.8 μg/day). Quintiles 2, 3, 4, and 5 had means (with ranges) of 0.7 μg/day (0.0 to 2.0), 2.3 μg/day (0.5 to 5.8), 11.1 μg/day (3.0 to 32.9), and 497.5 μg/day (23.0 to 7264.1 μg/day), respectively, exhibiting a skewed distribution of intake.

Trends toward greater intakes in Hispanics and in females were observed. Among the furocoumarins measured, bergamottin contributed most significantly to adults' intake (43.7 μg/day; SE = 7.2), followed by 6′7′‐dihydroxybergamottin (41.6 μg/day; SE = 9.6), bergaptol (11.4 μg/day; SE = 1.6), bergapten (5.5 μg/day; SE = 0.9), epoxybergamottin (3.1 μg/day; SE = 0.8), 8‐methoxypsoralen (2.7 μg/day; SE = 0.5), and psoralen (1.9 μg/day; SE = 0.5). The foods that contributed most significantly to furocoumarin intake among consumers were grapefruit (44.0 μg/day), grapefruit juice (16.9 μg/day), lime juice (8.1 μg/day), parsley (5.6 μg/day), lemon juice (3.9 μg/day), lime (0.9 μg/day), celery (0.8 μg/day), carrot (0.3 μg/day), and orange juice (0.1 μg/day).

Furocoumarin intake varies widely among the U.S. population in this cross‐sectional study, and is skewed toward the right with high intake among some consumers. This study provides a basis for further research on the impact of furocoumarin intake on drug interactions and skin cancer.

Support or Funding Information

Funding source: University of Connecticut Research Foundation Research Excellence Program (PI: Dr. Ock K. Chun); National Cancer Institute Omnibus R21 (PI: Dr. Eunyoung Cho)