Green smoothies, chia pudding, energy bites — trendy health foods have taken over our Instagram feeds, preaching the gospel of “eating clean.”

But what does clean eating really mean and are the diets that the movement has inspired actually good for you? The Passionate Eye documentary Clean Eating: The Dirty Truth takes a look at some of these trends and whether they actually work.

What is clean eating?

The premise of eating “clean” is to improve your health by changing the way you eat. The movement promotes going back to the basics: natural and unprocessed foods, mostly fruits and vegetables, and more home-cooked meals.

Fears about genetically modified products, pesticides on foods and too much sugar and salt in our diets have helped the clean eating movement gain momentum.

SCENE FROM THE FILM: Social media and food trends.

The movement has also grown with the help of social media — most notably the photo sharing social media platform, Instagram. A search for “#cleaneating” on Instagram will garner millions of posts of perfectly plated food and the perfect bodies these posters attribute to their clean diets.

But, somewhere along the way, the meaning behind “clean eating” got lost.

The backlash against ‘clean’

“The gurus of clean are doing nothing wrong in helping people eat more healthily. But with their growing influence comes a responsibility to ground their promises in proof,” says Giles Yeo, a geneticist with the University of Cambridge in the United Kingdom in the documentary Clean Eating: The Dirty Truth.

Deliciously Ella is one of the faces of the clean eating movement. What started off as a blog turned into multiple cookbooks, two delis, and a line of food products.

Despite promoting a lot of the ideals of clean eating, she said the term's meaning has changed and has become too complicated and loaded.

SCENE FROM THE FILM: Deliciously Ella

“Clean now implies dirty and that’s negative and we shouldn’t have that,” she says. “It’s sad to me that clean has been taken so far out of how I think it was originally meant to be used by people.”  

Under the auspices of “clean”, people have drastically changed their diets — and not always for the better.

Here are a few of the diet trends featured in the documentary, Clean Eating:The Dirty Truth:


The originator: Dr. William Davis, author of Wheat Belly

The theory: Eliminating wheat (and gluten-containing grains) will solve many health issues.

Davis says a protein found in gluten triggers “the first step in generating autoimmune diseases”.

The proof? Part of Dr. Davis’s theory is backed by evidence — that in some people, gluten can trigger an immune response which is called a leaky gut — a syndrome that causes bloating, constipation, diarrhea and other symptoms linked to celiac disease.

Dr. Yeo notes that other studies suggest that eating gluten alone isn’t enough to create a health problem. One study, based on research on mice, found that gluten is only harmful if other problems also exist, such as a genetic predisposition, a faulty immune system, and imbalanced gut microbes.

Only a very tiny proportion of people (estimated at around 1 per cent) have trouble with gluten. For the rest of us, going gluten-free means following a challenging diet which doesn't have any health benefits but may increase your risk of nutritional deficiencies.

Alkaline Eating

The originator: Robert O. Young, author of The pH miracle

The theory: Young’s theory is that acidic foods, such as sugar, red meat, and dairy, can cause acid to build up in the body.

Since blood naturally has a slightly alkaline pH, it can’t balance that acid buildup, and it ends up in body tissues.

By eating more alkaline foods, such as avocados and broccoli, that delicate pH balance can be restored, he says.

“All sickness and disease can be prevented by managing the delicate pH balance of the fluids of the body,” says Young.

He believes that diseases come from changes in the body. “ In my world, the germ is nothing, the germ is just a product of its environment,” he says. “You don’t try to kill the germ, you change the environment.”

The proof? Young’s theory is not recognized by the medical industry, says Dr. Yeo.

Scientist Louis Pasteur proved that bacteria and viruses cause disease by coming into the body 

Not only is Young’s theory not recognized, says Dr. Yeo, but it goes against “all evidence-based medical dogma”.

Young also opened what he called the pH Miracle Living Center in California, where people would come for pricey treatments based on his alkaline theory. Young has since been convicted on two counts of practicing medicine without a license, according to the San Diego Union-Tribune.

“It’s anti-intellectual, it's anti-fact, it’s anti-evidence based and it's a very troubling narrative,” says Dr. Yeo. 

Plant-based diets

The originator: T. Colin Campbell, author of The China Study

The theory: People who eat an all plant-based diet have a lower risk for chronic diseases.

In 1966, as a young biochemist, Campbell was working in the Philippines helping undernourished children eat more protein. Anecdotally, he found that the families who consumed the most protein seemed to also have higher incidents of cancer.

It was that experience, along with other studies in the lab, which led Campbell to conduct The China Project.

Dubbed as “the most comprehensive study of nutrition ever conducted,” the project studied more than 6,500 people in 65 different regions of China. He was trying to find whether there was a connection between animal proteins and disease.

“What we learned was that diets that contained more and more animal proteins were associated with an increase in cancer rates and heart disease rates.” says Campbell.

The proof? Campbell himself has said there are issues with the study.

“Standing alone, it wasn’t enough, I’ve said this many times,” he said in the documentary.

While Campbell found links between increased animal protein consumption and diseases, the two variables weren’t directly linked.

To make the connection between the two, Campbell used high cholesterol levels as a proxy for high animal protein consumption.

“The problem is that many other factors, in addition to meat intake, influence cholesterol levels,” said Dr. Yeo in the documentary, citing genetics as an example. “Therefore in this situation, the proxy method may not be very reliable.”

Campbell maintains, however, that even without the scientific evidence to prove everyone should be meat-free all the time, he still sees it as a safe, healthy goal. “As we proceed in that direction, I don’t see harm occurring.”

Although other studies link high levels of red or processed meat consumption to bowel cancer, Yeo adds that there is no proof that eliminating animal-based foods from your diet is healthier.

For more on clean eating, watch Clean Eating: The Dirty Truth on The Passionate Eye.

Also on CBC