Think smoking's bad? Check out your fast-food diet

Smoking has been banished from the workplace, and the practice is heavily taxed by the government, which is probably cashing in on guilt as much as raising revenue or discouraging an unhealthy habit.

But those of us who look down on our nicotine-addicted friends while scarfing down high-fat, high-carb, sodium-rich, sugary fast food shouldn’t be so fast to judge.

Our smoker friends may be the ones called on to speak at our funerals.

A study published in the Lancet found that poor diet is the leading risk factor for deaths from lifestyle-related diseases in the majority of the world.

Researchers analyzing the diets of people in 195 countries looked at sales, spending and surveys to estimate the risk of death from heart disease, certain cancers and diabetes, as well as smoking, drug use and other factors.

"This study shows that poor diet is the leading risk factor for deaths in the majority of the countries of the world," says study author Ashkan Afshin of the Institute for Health Metrics and Evaluation at the University of Washington. Unhealthy diets are "a larger determinant of ill health than either tobacco or high blood pressure," he said.

It’s no secret that Americans, and people in countries that look up to us, don’t eat enough whole grains, nuts, seeds fruits or vegetables, and consume too many sugary drinks, salt and processed meat.

Not surprisingly, countries that follow the Mediterranean diet with its emphasis on fruits, vegetables, nuts and healthy oils like olive oil and omega-3 fatty acids, are the healthiest. That includes Israel, France, Spain and Japan. Mexicans consume a lot of healthy, whole-grain corn tortillas, but they consume too many sugary drinks.

Of course, it’s not easy or cheap to eat healthy fruits and vegetables — 800 million people around the world suffer from malnutrition, and 1.9 billion are obese, creating upwards of $5 trillion in healthcare costs.

And, even if everyone were to suddenly adopt a healthy diet, there simply aren’t enough healthy fruits, nuts, oils and vegetables to go around in a production and distribution system based on carbohydrates and starchy foods.

There is much we can do on an individual level, however, especially at this time of year, such as planting a garden to produce healthy fruits and vegetables for our friends and neighbors, and planning meals ahead to avoid the drive-through.