British Journal of Nutrition

Full Papers

Long-term strict raw food diet is associated with favourable plasma β-carotene and low plasma lycopene concentrations in Germans

Ada L. Garciaa1a2, Corinna Koebnicka1a3, Peter C. Dagneliea4, Carola Strassnera1, Ibrahim Elmadfaa5, Norbert Katza6, Claus Leitzmanna1 and Ingrid Hoffmanna1 c1

a1 Institute of Nutritional Science, University of Giessen, Giessen, Germany

a2 Human Nutrition Section, Division of Developmental Medicine, University of Glasgow, Yorkhill Hospitals, Glasgow, UK

a3 Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA

a4 Department of Epidemiology, Maastricht University, Maastricht, The Netherlands

a5 Institute of Nutritional Sciences, University of Vienna, Austria

a6 Institute of Clinical Chemistry, University of Giessen, Germany


Dietary carotenoids are associated with a reduced risk of chronic diseases. Raw food diets are predominantly plant-based diets that are practised with the intention of preventing chronic diseases by virtue of their high content of beneficial nutritive substances such as carotenoids. However, the benefit of a long-term adherence to these diets is controversial since little is known about their adequacy. Therefore, we investigated vitamin A and carotenoid status and related food sources in raw food diet adherents in Germany. Dietary vitamin A, carotenoid intake, plasma retinol and plasma carotenoids were determined in 198 (ninety-two male and 106 female) strict raw food diet adherents in a cross-sectional study. Raw food diet adherents consumed on average 95 weight% of their total food intake as raw food (approximately 1800 g/d), mainly fruits. Raw food diet adherents had an intake of 1301 retinol activity equivalents/d and 16·7 mg/d carotenoids. Plasma vitamin A status was normal in 82 % of the subjects ( ≥ 1·05 μmol/l) and 63 % had β-carotene concentrations associated with chronic disease prevention ( ≥ 0·88 μmol/l). In 77 % of subjects the lycopene status was below the reference values for average healthy populations ( < 0·45 μmol/l). Fat contained in fruits, vegetables and nuts and oil consumption was a significant dietary determinant of plasma carotenoid concentrations (β-carotene r 0·284; P < 0·05; lycopene r 0·168; P = 0·024). Long-term raw food diet adherents showed normal vitamin A status and achieve favourable plasma β-carotene concentrations as recommended for chronic disease prevention, but showed low plasma lycopene levels. Plasma carotenoids in raw food adherents are predicted mainly by fat intake.

(Received May 14 2007)

(Revised October 11 2007)

(Accepted October 22 2007)

(Online publication November 21 2007)


c1 Corresponding author: Professor Ingrid Hoffmann, fax +49 6419939059, email


Abbreviations: SRC, standardized regression coefficient