Want to shed that excess weight without changing what you eat at mealtimes? It’s not easy, but it is straightforward: Just control three critical behaviors and say hello to a lighter, leaner you.

As noted in a column earlier this month, a major attack point for vegetarian advocates is the notion that eating animal foods is inherently unhealthy. Even though they’re no longer the primary menu item for most fast-food franchisees, veggie activists just can’t wean themselves off demonizing burgers and fried chicken as the source of the nation’s dietary ills, especially obesity.

From a strategic standpoint, that’s understandable. Consider these three things from the Centers for Disease Control and Prevention:

  • More than one-third (34.9%) of U.S. adults are considered medically overweight or obese
  • Some 17% of adolescents and teen-agers are likewise judged to be obese
  • As many as 11% of infants and toddlers are obese, based on body length-to-weight ratios

That means nearly 95 million Americans are significantly overweight — to the point they’re at much greater risk for the most prevalent causes of death: heart attacks, stroke, diabetes and certain cancers.

And that’s CDC talking, not some huckster with a miracle diet plan.

Although obesity rates plateaued since 2003, it’s a public health crisis that remains ongoing, meaning that activist attacks on meat and dairy as the (alleged) culprits will continue, as well.

It’s time to put a stop to all that, however, because now there is growing evidence as to the real causes of obesity, and it’s not animal foods. In fact, it has nothing to do with anything you’d find on the center of anyone’s dinner plate.

Funnier, not fatter

Consider Drew Carey, the TV actor with the hipster glasses and trademark buzz cut. The “Price is Right” host and former star of “The Drew Carey Show,” which was set in his hometown of Cleveland: He spent much of his career as a hefty, jovial comedian who got laughs in spite of — or in some cases — because of his girth.

Then, about four years ago, he embarked on a rigorous program to lose weight, and managed to drop 80 pounds in less than a year. How? As he told People magazine at the time, he did it by sticking to “a diet high in protein, fruits and veggies,” and doing a “challenging” 45-minute cardio workout virtually every day of the week. That’s a virtually universal prescription — added protein, reduced carbs and lots and lots of exercise.

Look, with the exception of a very small cohort of XXL men who list their occupation as “Offensive Lineman,” nobody wants to be packing around excess tonnage. It doesn’t feel good, it doesn’t add to the enjoyment of everyday activities and, a few funnymen like Carey excepted, doesn’t get you to head of the line at auditions for a lucrative role in television or the movies.

Although obesity is extremely difficult to reverse, research has pinpointed some key causative factors. If you listen to the food companies, of course, their answer is predictable: Eat a “balanced” diet, which allows for plenty of whatever processed products or sugar-loaded cereal they’re marketing, coupled with a mythical regiment of “regular exercise.”

About the only regular exercise most adults get, unfortunately, is yelling at the TV during football games or political debates.

No, a much better cause for obesity is expressed in three words: Stress, soda and sitting.

Get rid of all three, or at least reduce their prevalence in your lifestyle, and while problems with overweight/obesity won’t be eliminated, I guarantee they’ll be greatly mitigated.

Stress is probably the key factor, and one virtually nobody takes seriously. Yet chronic stress wreaks havoc on the body, producing a hormonal imbalance that triggers excessive storage of fat, while actually breaking down muscle tissue and decelerating one’s metabolism.

There are dozens of ways to alleviate stress, including treating yourself to a great steak or big ol’ plate of barbecue. Pick one and stick with it.

Drinking soda is next on the hit list. A single bottle of “regular” soda contains up to 18 teaspoons of sugar, or about 250 calories you don’t need. The link between sugar consumption and increased risk of heart disease and diabetes is now as strong as the connection between smoking and lung cancer. The risk is so significant that the American Heart Association came out with guidelines last year urging women to consume no more than 100 calories of sugar a day, and men no more than 150.

Translation: Can the soda.

Finally, new studies analyzing the impact of long hours sitting at computers, in cars and on couches have revealed such depressing data that the question is being asked, “Is sitting the new smoking?”

That’s the Mayo Clinic doing the asking, by the way.

Among its other ill effects — such as higher risks of the aforementioned heart disease and diabetes — sitting for prolonged periods causes the body to go into what Mayo Clinic endocrinologist James Levine calls storage mode.

And guess what’s being stored?

When it comes to reversing obesity, the food that comprises our daily meals is actually a minor part of the problem. Sure, it helps to cut down on junk food and refined carbs, and it wouldn’t hurt to engage in at least some kind of activity, like walking, to better balance our sedentary lifestyles.

But eliminating those three dirty words that define too many people’s lifestyles is where the ultimate solution lies.

Dan Murphy is a food-industry journalist and commentator.