Here is the best health and nutrition advice you will ever receive: Never diet again! Americans are a faddish people. In the business world this makes us great, because innovation requires an entrepreneurial spirit and a willingness to try new things. In the dietary world, however, our creative souls have made our respective bodies, err, fat.

Health fads have been around generally since Adam munched on the poison apple. In more recent decades, though, they have grown exponentially. In my lifetime alone, people have given up salt, caffeine and fat. (Indeed, many of you beautiful sorority girls have given up eating altogether.) Now, of course, thanks to Dr. Robert Atkins, Americans have sworn off carbohydrates. This has all been very good news for the diet industry, which is worth an estimated $40 billion in the United States. Yet despite this outlay of creativity and capital, the American waistline has only grown wider.

Here’s the reason why: Diets are for high school wrestlers trying to make weight, not for healthy individuals trying to keep it off. Healthy people cultivate and maintain healthy lifestyles; unhealthy individuals may dabble in dietary trends, but they ultimately give them up and revert to their unhealthy ways. But we’ll return to this in a moment. Let’s first look at the problem.

The single greatest public health threat is what the World Health Organization has dubbed “”globesity”” – the dramatic rise of grossly overweight individuals in the world’s population. In many countries, more than half of the population is overweight. In the United States, according to the WHO, almost one-third of adults are thought to be obese. And the numbers are rising. In 1995, there were an estimated 200 million obese adults worldwide. Today, there are more than 300 million.

Aesthetics aside, it almost goes without saying that obesity is a very bad thing. Being overweight has been implicated in causing diabetes, cancer and, above all, heart disease. The latter is the world’s greatest cause of death, even more so than AIDS, cancer and war.

Who’s to blame for this growing worldwide epidemic? Apparently, we are. According to a study conducted by the international marketing group RSCG Tatham Partners, 90 percent of Americans believe they are personally responsible for their weight. In other words, nine out of 10 Americans readily admit that even if they were born as chubby children, the shape they take as adults is ultimately the result of personal choices.

Some research does indicate that it may be more difficult for certain people to lose weight as easily as others because of a genetic predisposition to weight gain and fat storage. But even if individuals have a genetic predisposition to weight gain, their food energy intake must still exceed their energy output in order for them to actually gain weight.

Anecdotally, at least, this makes sense. For instance, try to think of a person who both eats healthy and exercises regularly but is also overweight or obese. My sense is that you will not be able to think of a single individual who fits that bill. The reason is that if you’re not eating the wrong things, and you’re doing just enough to burn what you eat, you will not gain weight – no matter who you are.

So, we are left with this dilemma: People are willing to take personally responsibility for their weight, but they are unwilling to do what it takes to achieve their ideal weight.

And here’s the rub: Once people gain weight, it is hard for them to lose it. Once they are used to Jumbo Jacks and milkshakes, it’s hard to switch to tuna salad and mineral water.

But, there’s a silver lining. Good habits are also hard to break. If you begin to eat well and exercise consistently, you will find that you actually enjoy doing both of those things. Jumbo Jacks won’t sound so good, and those who buy into the South Beach diet will begin to look a little ridiculous.

There is no quick and easy way to lose a beer gut or to drop three dress sizes, and a magic diet pill or a new food fad will certainly not help with either of those goals. Instead, cultivating and maintaining a healthy lifestyle through a series of healthy choices is the only real way to achieve your dietary ambitions.

Eating healthy should not be punishment, but it does require a little planning and discipline. Plan A, step 1: Swear off fad diets, forever.

Jon Riches is a third-year law student. He can be reached at letters@wildcat.arizona.edu.