Smoking or Obesity: Which is Deadlier?

“In terms of life expectancy, we feel being overweight is as bad as cigarette smoking.” These are the words of clinical epidemiologist and Professor of Medicine at McGill University, Dr. Steven Grover.

Grover and his colleagues recently used the health data from 4,000 men and women to develop a computer model capable of estimating the effect of an individual’s body mass index (BMI)—a measure typically used by physicians to gauge obesity by comparing a person’s height and weight—on his or her life expectancy.

They found that overweight individuals (BMI greater than 25 but less than 30) live an average of three years less than those in the healthy BMI range (between 18.5 and 25). This number doubled for obese individuals (BMI greater than 30 but less than 35), who saw a six-year reduction in their life expectancy. The news was even worse for very obese individuals (BMI of 35 or higher), who were found to potentially be cutting their lives short by eight years, simply due to their excess weight.

Beyond an unnecessarily shorter life, study authors also claim that an increased risk for developing cardiovascular disease and diabetes means that people who carry unhealthy poundage could be cheating themselves out of “nearly two decades of healthy life,” according to a university press release.

Is smoking worse?

The fact that being overweight is unhealthy is not exactly earth-shattering, but what about Grover’s initial claim? How does being too heavy stack up against one of the unhealthiest lifestyle habits known to man: smoking?

A 2014 report from the Centers for Disease Control and Prevention (CDC), concluded that smoking can slash a person’s life expectancy by a decade, on average. And, like obesity, being a chronic smoker (defined as having more than 100 cigarettes in a lifetime) puts a person at greater risk for developing numerous harmful health conditions, including arthritis, cancer, decreased immune function, diabetes, lung disease, gum disease, cardiovascular disease, Crohn’s disease and inflammation, among others.

The good news

Going by the numbers alone, it appears that obesity is still the lesser of two evils when it comes to life expectancy. But there is some hope for those who are travelling down either (or both) unhealthy paths.

Some of the damage done by smoking and/or being overweight can be reversed, if the person adopts healthier lifestyle practices.

Smokers who kick their habit by 34 could recoup their lost decade of life. Those who quit before age 44 could regain nine years, and ceasing to smoke by 59 could enable an individual to get back anywhere from four to six lost years, according to the CDC researchers.

When it comes to obesity, “The pattern is clear—the more an individual weighs and the younger their age, the greater the effect on their health,” says Grover. He and his team are currently delving into how losing weight can affect health outcomes for overweight and obese individuals, though existing research suggests that even body weight losses of just five or ten percent could be beneficial to the health of obese individuals.

The bottom line? It’s certainly better to never smoke and always stick to a healthy diet and exercise program, but even if you’ve fallen off the wagon of health, there’s no time like the present to quit and get fit.

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Magdalena J.
Past Member 3 years ago

Thank you!

Panchali Yapa

Thank you

Panchali Yapa

Thank you

Jean G.
JeanisAWAY G3 years ago

Thanks for sharing, although have doubts about contents.

Ana MESNER3 years ago

Thank you for posting.

Marion Friedl
Marion Friedl3 years ago

There´s so much poison in our surrounding, even mushrooms in Germany are still radioactive, more than 28 years after Tschernobyl, so I think there´re more influences which cause cancer than smoking, Helmut Schmidt, a former Chanceller, must be 95 or so and smokes cigars every day, so if someone´s resistant against cancer it doesn´t seem to matter how he lives... The world´s just unfair sometimes, my grandpa whom I never saw because he died before I was born had stomach cancer, he had never smoked, never drunken alcoohol and only eaten very few meat, maybe on Sundays, and a lot of fruits and vegetables instead!!!

Kamia T.
Kamia T3 years ago

This is almost like saying which is more poisonous, cyanide or arsenic. Who cares? They'll both kill you if you keep engaging in them. And someone got funded to do this study, instead of starving families or pets who need help. Shameful.

E. Talamante
E. Talamante3 years ago

Good to know. I wonder, as others have mentioned, about the increased risk with added elements such as alcohol or drugs (including some prescription pain-killers).

Roberto Meritoni
Roberto Meritoni3 years ago

Thanks for this very interesting article

Angela P.
Angie P3 years ago

Thanks for article.