A 2005 review of 13 worksite programmes with environmental changes concluded there was strong evidence for an effect on dietary intake but inconclusive evidence
for an effect on physical activity and no evidence for an effect on health risk factors [34]. The purported strongest evidence was for diet despite the fact that all dietary
outcomes were self-reported rather than objectively measured. Similarly dietary outcomes in our review were predominantly self-reported, except in three of the 16 studies where sales data were used to supplement self-reported dietary changes [28,32,33]. There is an
urgent need for future worksite dietary intervention studies to include objective measures of dietary behaviour and environments. Examples of such objective measures
include body weight, biological risk factor levels such as blood cholesterol, canteen and/or vending machine sales data, and nutritional analysis of foods available at worksites. Similar recommendations have been made with respect to evaluation of worksite physical activity interventions[14]. Future studies should also consider assessing
dietary intake outside the workplace because of the potential for compensatory behaviours elsewhere.