[1] Univ Dundee, Sch Dent, Dept Dent & Oral Hlth, Dundee, Scotland
[2] Univ Ottawa, Dept Epidemiol & Community Med, Ottawa, ON, Canada
[3] Utah State Univ, Dept Nutr & Food Sci, Logan, UT 84322 USA
[4] Univ Dent Hosp Manchester, Biomed Res Ctr, Manchester, Lancs, England
[5] Univ Dent Hosp Manchester, Dept Oral Hlth & Dev, Manchester, Lancs, England