Healthy weight people take fewer sick days. According to the Centers for Disease Control and Prevention, a healthy weight man misses about three days of work for illness or injury each year. An overweight or obese man misses approximately five days. Someone working 237 days a year can do more than someone working 235 days per year — though not orders of magnitude more. In theory, if a wellness program could help someone achieve a healthy weight, that could reduce absenteeism.
Risk factors correspond with higher medical costs. ConAgra, the packaged foods company, has run a wellness program for six years. According to VP of Human Resources Charlie Salter, in its current iteration, employees get a bonus Health Savings Account contribution for participating (taking a health assessment and doing a finger prick blood test). Then they get insurance premium reductions for achieving normal ranges (or achieving major progress) on five health factors including body mass index (BMI), cholesterol, blood pressure, smoking, and blood glucose. The company found that "people with at least four of these health risks are 2.5 times more costly than people with two risks or less," Salter says.
People like wellness programs. Good ones offer access to exercise advice and convenient health screenings, which busy people appreciate. Regardless of outcomes, these make people feel like their employers care, which can boost engagement and, potentially, productivity.
Some studies find measurable benefits. One meta-analysis of 42 corporate wellness studies found a 25% reduction in absenteeism and sick leave, a 25% reduction in health costs, and a 32% reduction in workers compensation and disability costs. A recent report from the National Business Group on Health and Towers Watson found that organizations with strong wellness programs had lower rates of obesity than "low-effectiveness" companies, and had lower unplanned absence rates (3.3 vs. 4.0 days/year).