Unhealthy lifestyles and overweight are common among blue collar workers. To evaluate a nutrition education intervention in construction workers to prevent chronic diseases. One hundred forty two participants were randomly assigned to an experimental group (n = 69) and or a control group (n = 73). The experimental group received nutrition education consisting in individual lifestyle counseling, group workshop, group counseling in healthy lifestyles, and environmental intervention. At baseline and after one year of intervention, clinical evaluations consisting in laboratory determinations, anthropometry and nutritional assessment evaluation were carried out. The experimental group experienced a significant decrease in waist circumference, total cholesterol, triglycerides, and an increase in HDL cholesterol. A significant reduction in total calorie intake, especially at the evening snack was observed during week-days. The same reduction in total calories occurred at dinner during the week-end. A significant increase was observed in the consumption of fruits, vegetables and fish. In the control group there was a significant increase in weight, waist circumference, body mass index, glucose and insulin, without changes in total calorie intake or healthy food consumption. High soft drink consumption did not change in both groups. In construction workers, integral nutrition intervention at the individual, group and environmental level had an impact in nutritional and biochemical indicators.