The vast majority of research on the efficacy of workplace interventions focus on the role of exercise and physical activity. Indeed, many studies show that educating employees about the mental, social, and physical health benefits of exercise leads to an increase in physical activity.
Implementing worksite exercise programmes which can range from recommending 1,000 steps a day to providing in-house aerobic and strength training during protected time over an extended period improves employees’ health: physical health benefits are better body mass index or BMI, blood pressure (BP), HDL cholesterol, body fat proportion, and waist circumference, while mental health benefits include improved psychological mood and wellbeing. These workplace interventions are influential in achieving greater productivity as employees report better job satisfaction and spend fewer days absent from work due to ill health.
In contrast, studies on healthy eating workplace interventions show more mixed results. The health benefits of eating whole grains, fruits and vegetables are well established for community samples. But compared to the benefits from workplace physical activity interventions, programmes which focus on healthy eating tend to achieve less dramatic results. A review by Anderson and colleagues (2009) indicates small though significant reductions in weight and improvements in BMI for 6 and 9 randomized controlled studies respectively. In another review, Mhurchu and colleagues (2010) suggest that changing the environment (e.g., providing healthy choices in the canteen), as well as educating employees about the benefits of healthy eating, does bring about dietary changes. Furthermore, few studies measure objective outcomes such as BMI or corporate outcomes such as absenteeism.
This may be because interventions which focus primarily on changing eating patterns are not as effective as those which increase physical activity and encourage healthy eating. Alternatively, other factors may be at play. A randomized controlled study by Barrington and colleagues (2012) shows that even at baseline (before any workplace intervention takes place), workers who report higher levels of stress show fewer healthy behaviours — a tendency to eat while doing other activities and less leisure-time exercise. Moreover, those unaware of preoccupied eating also eat fewer fruits and vegetables and more fast food.
Workplace interventions may need to consider the impact of stress levels and take steps to counter its effects on eating and exercise behaviours among employees. While a holistic approach which tackles food choices, physical activity, and stress management is commendable, it may also be important to provide employees with effective strategies for managing stress. A recent study showed that social support was not helpful for improving BMI, even though there was a positive correlation between workplace social support and physical activity/fruit-vegetable intake (Tamers et al., 2011). Instead, interventions which specifically target how employees manage their stress may be the way to go.