(CNN) It's been a bad few weeks for memes.

In mid-September the European Parliament passed a new copyright law that some have dubbed a "meme ban."

Then Sweden's advertising watchdog ruled that the popular "distracted boyfriend" meme is sexist

Now, academics have told British lawmakers that internet memes may be contributing to the UK obesity crisis and doing harm to teenagers on a significant scale.

Memes carry dangerous health-related messages and make light of unhealthy eating habits, researchers from Loughborough University wrote in a letter sent to a British parliamentary committee.

"A substantial number of individuals on Twitter share health-related Internet memes, with both positive and negative messages," they wrote, noting that many "contain inappropriate material."

A picture of an overweight child with the caption "Free food? Count me in!" was sent along with the letter as an example of a meme the researchers found dangerous.

The academics were also concerned by a meme that created a human-like body from pictures of pizzas and hamburgers, with frankfurters used for limbs and a smiley-faced potato for a face.

The body was captioned "me" and placed alongside images of three well-defined bodies for comparison.

"The vast majority of sharers display little, if any, emotion when sharing these memes," the academics commented.

"Just washed this chocolate bar with soap," read the caption to another image included in the letter, along with #cleaneating.

"Internet memes are generally viewed as entertaining but they also represent a body of cultural practice that does not account for the specific needs and rights of teenagers," the researchers warned.

"Unhealthy lifestyles cost the NHS billions every year," they added, suggesting that "the dangers of inaccurate/inappropriate health messages" contained in memes could be a contributing factor.

Call to scrutinize memes

The letter was sent to a committee analyzing the effects of social media use on young people's health.

Its authors suggested teenagers should scrutinize the underlying themes in the memes they see, rather than simply enjoying them.

"It is worrying that Internet meme content... produces a predominate sense of happiness regardless of the underlying tone or image used," they wrote.

"If Internet memes carry political, corporate or other agendas without priorities tailored to the needs of 13-16-year-olds then they have the potential to do harm on a large scale," they added.

They also noted that memes "have the potential to normalize undesirable behaviors," and often "contain inappropriate material or ridicule others by race, gender, ethnicity, sexuality, body shape, religion, diet."