Research has shown that workplace health promotion (WHP) efforts can positively affect employees' health risk accumulation. However, earlier literature has provided insights of health risk changes in the short-term. This prospective longitudinal quasi-experimental study investigated trends in health risks of a comprehensive, eight-year WHP program (n = 523-651). Health risk data were collected from health risk assessments in 2010-2011, 2013-2014, and 2016-2017, applying both a questionnaire and biometric screenings. Health risk changes were investigated for three different time-periods, 2010-2013, 2014-2017, and 2010-2017, using descriptive analyses, t-tests, and the Wilcoxon Signed Rank and McNemar's test, where appropriate. Overall health risk transitions were assessed according to low-, moderate-, and high-risk categories. Trend analyses observed 50-60% prevalence for low-, 30-35% for moderate-, and 9-11% high-risk levels across the eight years. In the overall health risk transitions of the three time-periods, 66-73% of participants stayed at the same risk level, 13-15% of participants improved, and 12-21% had deteriorated risk level across the three intervention periods. Our findings appear to indicate that the multiyear WHP program was effective in maintaining low and moderate risk levels, but fell short of reducing the total number of health risks at the population level.