A high intake of conjugated linoleic acid does not affect liver and kidney function tests in healthy human subjects

Conjugated linoleic acid (CIA) is consumed widely as a supplement. It Causes hepatomegaly in animals, but toxicological data in humans are limited We therefore studied the effect of a high daily intake of CIA on liver and kidney function in healthy subjects. Twenty Subjects received 14 6 g cis-9,trans-11 CIA and 4.7 g trans-10,cis-12 CIA isomers a day for 3 weeks. Liver and kidney function was measured at 0, 3, 7, 10, 16, and 21 days. Mean values of all tests remained within normal limits Lactate dehydrogenase (mean +/- SD) increased from 290 9 +/- 43.6 to 322.5 +/- 60.7 U/L (p = 0.04) on day 21. One subject exceeded the tipper limit of normal of 450 U/L on day 21. to 472 U/L and another showed an isolated elevation to 555 U/L on day 7. gamma-Glutamyltranspeptidase increased from 12 1 +/- 5 9 to 13 5 +/- 6.2 U/L (p = 0.002) No one exceeded the upper limit of 50 U/L for men and 40 U/L for women A daily intake of 19.3 g CIA for 3 weeks does not produce clinically relevant effects on markers of liver and kidney function in healthy volunteers. (C) 2009 Elsevier Ltd. All rights reserved.