A new study has found that obesity can shorten one’s life by almost a decade.

Researchers at McGill University linked obesity with an increased risk of developing heart disease and type 2 diabetes — ailments that dramatically reduce both life expectancy and the number of years spent free of chronic illnesses.

Obesity and extreme obesity can reduce life expectancy by up to eight years and deprive people of as many as 19 years of healthy living, the study published Thursday in The Lancet Diabetes & Endocrinology concludes.

Researchers used data from the U.S. National Health and Nutrition Examination Survey to create a model to estimate the risk of disease based on body weight and then examined how excess weight contributed to years of life lost. The model found that the younger someone becomes obese, the more years he or she ultimately loses.

“The pattern is clear,” Dr. Steven Grover, lead author and Professor of Medicine at McGill University, said in the published study. “The more an individual weighs and the younger their age, the greater the effect on their health, as they have many years ahead of them during which the increased health risks associated with obesity can negatively impact their lives.”

Write to Eliana Dockterman at eliana.dockterman@time.com.