Conservative groups have offered stark warnings of an infringement on personal liberty, after the Obama administration implemented its ban on trans fats.

The Federal Drug Administration (FDA) said the restriction on trans fats – a staple of doughnuts, sprinkles and popcorn – could prevent 20,000 heart attacks and 7,000 deaths a year. The White House has described the ban, to be implemented by 2018, as a “massive win for public health”. The Center for Science in the Public Interest supports the ban. Many doctors support it too.

But not everyone is happy.

“It’s certainly counter to the idea of American liberty and freedom,” said Daren Bakst, from the Heritage Foundation, a conservative thinktank.

“It’s an overreach by the agency. The public will be extremely concerned.”

Between 2003 and 2013, the average daily consumption of trans fats, or partially hydrogenated oils, decreased by 78%, from 4.6g to 1g per person. Bakst said that decline showed that the ban was unnecessary.

“The industry has reduced the amount of trans fat in food products and the consumers are eating far less trans fat,” he said. “The question is: why in the world are they trying to address this now when it’s already voluntarily going down?

“It’s not just problematic when it comes to partially hydrogenated oils. It’s also problematic because it sets a dangerous precedent when it comes to other potential ingredients they could start trying to regulate.”

Trans fats are used in processed foods to prolong shelf life while adding texture and flavour. But they are considered worse than even saturated fats – themselves the bane of arteries everywhere – as a major contributor to heart disease.

“I just don’t know where it stops. There’s a lot of bad things out there that people shouldn’t be eating,” said Julie Gunlock, a senior fellow at the Independent Women’s Forum, a conservative personal liberty thinktank.

“The government should be educating people, giving out grants to scientists. That’s as far as I want to see the government going.”

Trans fats are known for their use in such American staples as sprinkles and various types of doughnuts. They are also present in dishes served at large chain restaurants, including Chili’s and Red Lobster. In May, Yahoo listed the worst-offending products in terms of trans fat contents. Pop Secret buttered popcorn, Olive Garden’s Sicilian cheesecake and Steak ’n Shake’s sausage gravy and biscuits featured prominently.

“These trans fats do still exist, they are incredibly unhealthy. But this is moving from telling us and educating us to making the decision for us,” Gunlock said. “With freedom comes the freedom to make bad decisions.”

Kentucky senator Rand Paul, who is running for the Republican presidential nomination in 2016, wrote to the FDA in March expressing his own discomfort. Paul, a qualified ophthalmologist, said there are “practical and process concerns” with the ban.

Jeff Stier, a senior fellow at the rightwing National Center for Public Policy Research, warned that the FDA had been infiltrated by health officials from the administration of former New York City mayor Michael Bloomberg. While mayor, Bloomberg banned trans fats from restaurants and smoking in public areas, and famously attempted to ban large-sized sodas.

“It is no surprise to see Bloomberg-style nanny-state policies in the Obama administration,” Stier said. “I don’t think the entire country wants Bloombergian policy.”

Stier said the ban on trans fats could set in motion a series of restrictions on foods that might be seen as unhealthy.

“It’s precedent-setting,” he said. “I’ve got a whole list of ingredients that could be next. Sugar can be attributed to lots of deaths. Is sugar generally recognised as safe? Maybe we should only allow minute amounts of sugar.”