a1 Washington Center for Clinical Research, 5100 Wisconsin Avenue, NW, Washington, DC 20016, USA
a2 Department of Medicine, The George Washington University School of Medicine, Washington, DC, USA
a3 Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA
Objective To examine whether a worksite nutrition programme using a low-fat vegan diet could significantly improve nutritional intake.
Design At two corporate sites of the Government Employees Insurance Company, employees who were either overweight (BMI ≥ 25 kg/m2) and/or had type 2 diabetes participated in a 22-week worksite-based dietary intervention study.
Setting At the intervention site, participants were asked to follow a low-fat vegan diet and participate in weekly group meetings that included instruction and group support (intervention group). At the control site, participants received no instruction (control group). At weeks 0 and 22, participants completed 3 d dietary records to assess energy and nutrient intake.
Subjects A total of 109 participants (sixty-five intervention and forty-four control).
Results In the intervention group, reported intake of total fat, trans fat, saturated fat and cholesterol decreased significantly (P ≤ 0·001), as did energy and protein (P = 0·01), and vitamin B12 (P = 0·002), compared with the control group. Intake (exclusive of any use of nutritional supplements) of carbohydrate, fibre, vitamin C, magnesium and potassium increased significantly (P ≤ 0·0001), as did that for β-carotene (P = 0·0004), total vitamin A activity (P = 0·004), vitamin K (P = 0·01) and sodium (P = 0·04) in the intervention group, compared with the control group.
Conclusions The present study suggests that a worksite vegan nutrition programme increases intakes of protective nutrients, such as fibre, folate and vitamin C, and decreases intakes of total fat, saturated fat and cholesterol.
(Received January 10 2009)
(Accepted November 22 2009)
(Online publication January 15 2010)