title: Effects of dairy products naturally enriched with cis-9,trans-11 conjugated linoleic acid on the blood lipid profile in healthy middle-aged men.
abstract: BACKGROUND
  Interest in the development of dairy products naturally enriched in conjugated linoleic acid (CLA) exists. However, feeding regimens that enhance the CLA content of milk also increase concentrations of trans-18:1 fatty acids. The implications for human health are not yet known.
  
  
  OBJECTIVE
  This study investigated the effects of consuming dairy products naturally enriched in cis-9,trans-11 CLA (and trans-11 18:1) on the blood lipid profile, the atherogenicity of LDL, and markers of inflammation and insulin resistance in healthy middle-aged men.
  
  
  METHODS
  Healthy middle-aged men (n = 32) consumed ultra-heat-treated milk, butter, and cheese that provided 0.151 g/d (control) or 1.421 g/d (modified) cis-9,trans-11 CLA for 6 wk. This was followed by a 7-wk washout and a crossover to the other treatment.
  
  
  RESULTS
  Consumption of dairy products enriched with cis-9,trans-11 CLA and trans-11 18:1 did not significantly affect body weight, inflammatory markers, insulin, glucose, triacylglycerols, or total, LDL, and HDL cholesterol but resulted in a small increase in the ratio of LDL to HDL cholesterol. The modified dairy products changed LDL fatty acid composition but had no significant effect on LDL particle size or the susceptibility of LDL to oxidation. Overall, increased consumption of full-fat dairy products and naturally derived trans fatty acids did not cause significant changes in cardiovascular disease risk variables, as may be expected on the basis of current health recommendations.
  
  
  CONCLUSIONS
  Dairy products naturally enriched with cis-9,trans-11 CLA and trans-11 18:1 do not appear to have a significant effect on the blood lipid profile.
authors.affiliation: Hugh Sinclair Unit of Human Nutrition, School of Food Biosciences and the School of Animal and Microbial Sciences, The University of Reading, Whiteknights, Reading RG6 6AP, United Kingdom. p.yaqoob@reading.ac.uk
authors.forename: Sabine
authors.initials: S
authors.lastname: Tricon
authors.forename: Graham C
authors.initials: GC
authors.lastname: Burdge
authors.forename: Emma L
authors.initials: EL
authors.lastname: Jones
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: Russell
authors.forename: Soraya
authors.initials: S
authors.lastname: El-Khazen
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Moretti
authors.forename: Wendy L
authors.initials: WL
authors.lastname: Hall
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Gerry
authors.forename: David S
authors.initials: DS
authors.lastname: Leake
authors.forename: Robert F
authors.initials: RF
authors.lastname: Grimble
authors.forename: Christine M
authors.initials: CM
authors.lastname: Williams
authors.forename: Philip C
authors.initials: PC
authors.lastname: Calder
authors.forename: Parveen
authors.initials: P
authors.lastname: Yaqoob
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000097:blood / Q000517:prevention & control; D008076:Cholesterol, HDL / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D008078:Cholesterol, LDL / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D018592:Cross-Over Studies; D003611:Dairy Products / Q000032:analysis; D004311:Double-Blind Method; D006801:Humans; D007328:Insulin / Q000378:metabolism; D007333:Insulin Resistance; D007536:Isomerism; D044243:Linoleic Acids, Conjugated / Q000737:chemistry / Q000494:pharmacology*; D050356:Lipid Metabolism / Q000187:drug effects*; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D012307:Risk Factors
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D007328:Insulin; D044243:Linoleic Acids, Conjugated