What does 'clean eating' actually mean?

For the last decade, “clean eating” has enjoyed its moment in the spotlight. 

While there’s no scientific definition, it generally means diligently avoiding anything processed and instead filling your plate with “whole” or “real” foods. 

Advocates of clean eating are often quick to demonize certain foods and encourage you to cut out specific foods or food groups. This might include sugar, grains, gluten, or dairy.

No scientific evidence supports the benefits of clean eating. In fact, a restrictive eating pattern can negatively affect your physical and mental health

In this article, we explore the differences between clean eating and healthy eating. We then look at tips for building healthy eating habits.

At ZOE, we know there’s no one-size-fits-all approach to nutrition. 

With the ZOE at-home test, you can learn about your personal blood sugar and blood fat responses, and which “good” and “bad” bugs are living in your gut.

Take our free quiz to get started.

Clean eating vs. healthy eating

There are many reasons why people want to eat clean.

For some, clean eating seems like an effective way to lose weight. Others may be looking to improve their energy levels or support their gut health

However, billing clean eating as the way to achieve these goals is a black-and-white way of thinking. 

While focusing on whole foods and limiting some processed products is a good idea, it’s important to distinguish clean eating from healthy eating. 

Clean eating is based on restriction — proponents think of “clean” foods as more pure and thus superior. This suggests that other foods are “dirty” or unhealthy. 

At ZOE, we believe that every food has a place on our plates. Food is a source of pleasure and should be enjoyed without hard and fast rules. 

Eating a variety of foods ensures that we meet our nutritional needs and nourish the trillions of microbes in our gut microbiomes. 

Strategies for healthy eating

Healthy eating doesn’t need to be restrictive. Quite the opposite — it requires us to enjoy a widely varied diet. 

Below are some tips for enjoying the benefits of abundance. 

Diversify your diet

The research is clear: Eating a variety of plants leads to a healthier microbiome. Plant foods are a great source of fiber, which our gut bugs love. 

But that doesn’t mean just eating plain fruits, vegetables, and whole grains. Coffee and tea, nuts and seeds, spices, and herbs also count, for example. 

Eat the rainbow

You may be familiar with this phrase, with good reason. Brightly colored fruits and vegetables are packed with polyphenols

Polyphenols are chemical compounds with many health-promoting functions. They’re associated with a reduced risk of cardiovascular disease and certain cancers.

When you aim for a variety of colors, you eat a variety of foods.

Embrace fermented foods

Add sauerkraut or kimchi to your sandwich, or sip on some kefir or kombucha. Live yogurts, aged cheeses, tempeh, and miso also contain millions of beneficial probiotics. 

A recent study led by Prof. Christopher Gardner, a member of ZOE’s scientific advisory board, found that regularly eating fermented foods can lower levels of inflammation and increase the abundance of good bacteria in your gut.

Limit ultra-processed products

Ultra-processed foods contain highly processed ingredients with added sugars, fats, and other additives to make them more palatable. 

Store-bought cakes, cookies, soft drinks, and packaged snacks often fall into this category.

Eating a lot of ultra-processed foods increases your risk of obesity, type 2 diabetes, and poor gut health

What are processed foods?

One nonnegotiable aspect of clean eating is the elimination of processed foods.

Unfortunately, this fails to recognize that food processing is an ambiguous, misunderstood concept. 

While there's no clear definition of “processed food,” the United States Department of Agriculture suggests that the term describes any food that has been changed from its natural state.

This is a fairly vague definition, as it includes cooking, canning, freezing, drying, and fermenting. 

Processing often makes food safer, tastier, and easier to eat. It can also make the nutrients in food more readily available and help prevent nutrient deficiencies.

As you might have noted, most food we eat has undergone some form of processing.

Olive oil, sourdough bread, live yogurt, and sauerkraut are all processed foods that can be part of a healthy, balanced diet. 

But it’s important to distinguish this type of food processing from ultra-processing. Ultra-processed foods are often energy-dense due to their high amounts of added sugars, fats, and salt. 

Also, ultra-processed foods often contain emulsifiers, artificial flavorings, and sweeteners, and they tend to have little or no fiber. 

We know that our long-term dietary pattern is the best indicator of our health.

So, it’s important to make sure you have a diet that you can sustain over a long period. This may include ultra-processed foods once in a while.

Health risks of clean eating

Social media and wellness blogs are awash with tips and tricks for eating clean. 

What starts as a desire to be healthy can lead to an unhealthy fixation. A compulsion to eat only “clean” foods considered “pure,” “whole,” or “natural” is a form of disordered eating called orthorexia nervosa

There’s no official diagnostic tool for orthorexia, so it’s hard to know how common it is. 

A 2013 review estimates that orthorexia might affect around 7% of the general population. The authors suggest that it might affect up to 58% of people in high risk groups, such as healthcare professionals and dancers.

However, a 2017 study places the estimate lower, suggesting that under 1% of the U.S. population has orthorexia.  

As the clean eating trend has been popularized on social media, it may come as no surprise that teenagers and university students can be particularly at risk.

Not only can excessively avoiding certain foods and food groups increase anxiety, it can also lead to malnutrition and nutrient deficiencies

This is a pressing concern because young women — the population most likely to identify with this trend — already have a higher risk of iron deficiency anemia

If you’re concerned about your eating habits and mental health, it's important to talk about this with a healthcare professional.


Nourishing our bodies with many different fruits and vegetables, legumes, pulses, and whole grains ensures that our microbes are well-fed and our taste buds are delighted. 

Clean eating takes it one step further and embraces the virtues of going sugar-free, grain-free, gluten-free, and dairy-free, as well as cutting out processed foods. 

The term “processed” is often misunderstood — it doesn’t mean a food is bad for you. In fact, processing can make food safer to eat and easier to digest.

And processing food can even increase the health benefits. For example, fermentation is a type of processing.

An obsession with eating clean, pure, or natural food can lead to orthorexia, a form of disordered eating. This condition can have serious long-term effects on physical and mental health. 

At ZOE, we encourage you to focus on what you’re putting on your plate rather than what you’re taking away. 

Enjoy a variety of brightly colored plants, feast on fermented foods, and remember that there’s a place for all foods in a healthy, sustainable diet.  

We know that nutrition is complicated. With the ZOE at-home test, you can learn about your personal blood sugar and blood fat responses and which “good” and “bad” bugs are living in your gut.

Take our free quiz to get started.


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