The Food and Drug Administration has taken the first step to ban trans fat. In so doing, it also took the first step to drastically undermine the integrity of the agency. Instead of protecting Americans from unreasonable risks, the agency has effectively decided to change its mission to nutrition activist.

In its own announcements regarding the proposed ban, the agency boasts how, for more than a decade, companies and consumers have taken significant action to reduce the consumption of trans fat. In 2003, the consumption of partially hydrogenated oils, which are the major dietary source of trans fat, was 4.6 grams per day. In just a decade, it has declined to about 1 gram per day in 2012. This is nearly an 80 percent reduction.

This is a classic example of a solution in search of a problem. There has been a massive decline in trans fat consumption, yet the FDA still feels compelled to ignore the voluntary and informed choices of Americans.

It’s not even trying to improperly change behavior, because the public is behaving exactly the way the government thinks it should. Instead, it has decided the public shouldn’t be given the ability to make free choices, and as a result is taking the extreme action of imposing a ban.

The FDA’s actions should make everyone nervous because it’s far bigger than banning trans fat. The agency is trying to expand its power from banning food ingredients that are dangerous to banning ingredients that the government thinks aren’t as healthy as other alternatives. The FDA is trying to dictate dietary lifestyle, not protecting Americans from unreasonable harm.

Individuals don’t keel over and die after eating microwave popcorn containing trans fat. Nor do they die if they eat some popcorn over their lifetime. Of course, as with salt, the more an individual eats of an unhealthy food, the likelier the risk of potential harm. As with so many things, the dose makes the poison.

This is a question of freedom. It’s not a referendum on whether people should eat trans fat. The question is whether individuals or government bureaucrats should decide what we can put into our bodies. Government interference on dietary choices presumes that people are too ignorant to make basic choices.

It’s hard to imagine a greater intrusion into our lives than telling us how to perform a basic function of life: eating.

This FDA power grab won’t stop with trans fat. Once the precedent has been established that the FDA will serve as the public’s nutritionist, both added salt and sugar will be in the crosshairs of the agency. There are already attempts by activists to go after these ingredients.

The ban will likely lead to higher food prices as food companies have to find alternatives to trans fat. In addition, trans fat has many important benefits, such as improving taste and extending the shelf life of food. Ironically, many companies will start using saturated fat again. It wasn’t that long ago that trans fat was thought to be the healthier alternative to saturated fat.

The FDA plays an important role to ensure that we have a safe food supply. This role, though, doesn’t include trying to dictate our diet. There should be immediate hearings in Congress on how to rein in the FDA. The law should be clarified to reflect the intent of Congress when it sought to protect Americans from unreasonable dangers associated with food ingredients.

The last thing we need is to protect Americans from an out-of-control agency driven by an activist agenda.

- Daren Bakst is a research fellow in agricultural policy at The Heritage Foundation.