The Effects of Processed Foods on Your Nutrition and Health

The Effects of Processed Foods on Your Nutrition and Health

The Effects of Processed Foods on Your Nutrition and Health


If you are someone who is interested in health, I am sure you’ve heard that eating processed foods should be minimized or avoided altogether. We all seem to have some idea of what “processed” means, but you might be interested to learn that not all processing is bad for us. 

What is Processed Food?

As with most things, there is a spectrum of processing and a spectrum of the impact it has on our food. Processing simply means doing anything to a food that alters it. By this definition, cutting and cooking are considered processing. Clearly, we all process our foods to some extent. But, the more we process a food, the farther away it gets from the original food and the worse it is for our health.

To illustrate this point, let’s take the example of an apple. Eating a whole apple requires us to take a bite, chew it up and swallow it. This takes some time. During this time, our body is using it’s resources to slowly digest the apple. Digestion begins in the mouth as enzymes in our saliva begin to break down the starches and fats in our foods. Once the apple is chewed into smaller bits and swallowed, it takes more time for the apple particles to be broken down further and the nutrients and fructose to be released. With this process, the sugars are absorbed slowly by the body so we do not get a big spike of sugar in our bloodstream and, therefore, no big spike of insulin. 

Harmful Effects of Processed Food

Now, take that same apple and puree (process) it in a smoothie. While we are still getting all of the nutrients of the whole apple, we no longer need to bite and chew  - that part of the eating process has already been done for us. While a smoothie is delicious, it is usually consumed more quickly than it’s individual parts because all we have to do is sip and swallow. Unfortunately, this means that the sugar in the apple hits our bloodstream more quickly and causes a bigger glucose spike. 

Now, process that apple a bit more and make it into apple juice and the sugar is so rapidly absorbed that it causes a huge spike of sugar and a resulting spike in insulin which, if done repeatedly will, over time, lead to insulin resistance and Type 2 diabetes.

So, clearly, we can consider the pureed apple a processed food and the apple juice a highly processed food (UPF). 

Benefits of Processed Food

To be fair, there are some benefits to highly processed foods. The processing was developed to stabilize foods so they can reach more people and not easily spoil (think apple juice compared with a fresh apple). The problem is that these highly processed foods are typically low in nutritional value, high in calories, and high in refined oils. As a society, we tend to process our commodity crops like rice, wheat, soy and corn because they are inexpensive. To stabilize these foods and make them easy to store and transfer without spoiling, we remove the fiber, essential fatty acids, micronutrients, and enzymes. Once all of those parts are removed, what is left is ground into a powder which is highly resistant to spoiling. At that point, refined oils are added to the powder. These refined oils are also used extensively because they are cheap. These oils are created through a series of intense processing (using high heat and chemical solvents) that make the end product closer to a plastic than a food. After the oils are mixed in, other chemicals are added to make this mixture palatable. These are non-biological substances that add flavor and color. To increase the appeal of these products, sugar and salt are often added so the end result is soft food that is highly addictive. 

What are Ultra Processed Foods - Why Are They Bad?

Described like that, these processed foods sound pretty awful. But, thanks to science and marketing, they taste great and fill the shelves of our grocery stores. Since we have all eaten some sort of this ultra processed food at some point, let’s take a look at what these “foods” are dong to our bodies. 

To start, I fully believe that every bite of food we ingest sends information to the various systems throughout our bodies. This information impacts how those systems run and how our genes are expressed (epigenetics). So, if we are eating foods that our bodies recognize as food, each system gets what it needs to run smoothly and we feel healthy. However, if we are ingesting chemicals and other things that our bodies don't recognize, trouble soon follows. And, that trouble starts as soon as we take a bite of these UPFs. 


Why We Tend to Overeat These Foods

Think about it. Most processed foods are soft so we don’t need to chew them very much. Remember the apple? The ultra-processed foods have been broken down for us so we get a concentrated amount of sugar and salt. Additionally, we tend to eat more quickly when we don’t need to chew the food. Not chewing and eating quickly impacts the receptors in our guts that turn off ghrelin (the hunger hormone) so we often don't feel full or satisfied until we have overeaten. 

Also, there are always added flavors in these UPFs. Just like the softness of the food, these flavor enhancers lead to overeating. In fact, they are designed to lead to overconsumption because these food companies want us eating more of their products. Added to the overconsumption issue, these foods are almost always high in calories and low in nutrients. Remember, all of the fiber, essential fatty acids, micronutrients, and enzymes were removed during the processing. What is added back in to make it taste good is often sugar, salt and chemically manufactured flavoring, all of which have no nutritional value. 


Now it’s easier to understand why we tend to overeat when we are eating UPFs - they are designed to be overconsumed! When we overeat UPFs, we are getting a lot of calories, a lot of sugar, a lot of salt, and very little nutrition. In most people, this leads to weight gain and obesity. And, as we all know, obesity is linked with a myriad of health problems like diabetes, cancer, high blood pressure and heart disease to name a few.

Food Additives

While we are talking about the impact of UPFs on our health, let’s look at what these non-biological substances (added colors, added flavors, preservatives, and emulsifiers) are doing in our bodies when we ingest them. Let’s think about our digestive systems for a minute. We all have a mouth, an esophagus, a stomach, and then about 30 feet of intestines. The digestive system is a beautifully designed system that takes what we ingest, breaks it down, accesses the information in the food, and then gets the food particles where they need to go. It’s actually pretty amazing! 

Effects on Digestion

Now, imagine what happens when we repeatedly ingest things that our bodies don’t recognize and don’t know what to do with. Because these added substances are so harmful, they are defined as toxins by Mark Sisson in The Primal Blueprint. He defines toxins as “human-made substances that disturb the normal, healthy function of your body when ingested. These include refined sugars, sodas, chemically altered fats, heavily processed foods, fried foods, and preservatives”. To better understand what is happening when we eat these toxins, remember that 70% of our immune system is in our gut, so the first thing that happens when there is a “foreign” substance in our digestive tract is that our bodies mount an immune response. And, what’s one of the most important parts of a normal immune response? It’s inflammation. Now, occasional inflammation in the gut is fine. But repeated or chronic inflammation in the intestines can lead to leaky gut which causes a host of problems throughout the body.

As if that weren’t enough bad news about these UPF’s, here is one more tidbit. Remember that the fiber is removed during the processing of these UPFs (which is why they need synthetic emulsifiers to create a palatable consistency). With no fiber in the food, we miss out on the prebiotics in fiber that feed and sustain the healthy bacteria in the gut causing these healthy bugs to die out and the more problematic bacteria to flourish.  Additionally, we are missing out on the short-chain fatty acids (SCFA) that are created when the fiber is broken down. These SCFAs are used to nourish our brain and immune system.

Processed Foods & Weight Gain


Whew! That feels like a lot of information so let me make it really clear. The end result of eating a diet high in UPFs is weight gain, systemic inflammation and an unhealthy gut. These conditions, individually and especially combined, lead to an increase in cardiovascular disease, cancers, metabolic disease, Type 2 diabetes, IBS, fatty liver disease, dementia, Alzheimers, anxiety and depression. Obviously, these are all illnesses we would like to avoid if possible. While we can’t completely control our future health, we can certainly control what we put in our mouths. And, UPFs are things we should be avoiding when possible. 

How to Avoid Ultra Processed Foods & Improve Your Health

To that end, here are some tips to help you do that:

Dr. Chris Van Tulleken (one of the leading experts in UPF research) defines UPF as “any food that is wrapped in plastic and has at least one ingredient that would not be found in a regular kitchen”. This seems pretty straightforward, but some of the ingredients can be a little bit tricky.  

If you are not buying a whole food (fruit, vegetable, eggs, cuts of meat, nuts, seeds, whole grains, and beans), always look at the ingredient list. A general rule of thumb is that there should be no more than five ingredients listed, and you should be able to pronounce all of them without a PhD in chemistry! 

Additionally, you should also avoid added colors and flavors, even when they are listed as “natural”. These have all been chemically altered so even if they taste the same as the real thing, our bodies may not recognize them as food. Often UPFs are fortified with vitamins and nutrients. This means that all of the naturally occurring goodness was stripped out during the processing and some synthetic vitamins and nutrients were added back in. While this has been helpful in the fight against vitamin deficiencies in areas where whole foods are not plentiful, it is always better to get our nutritional needs through whole and minimally processed foods.


Key Takeaways:

Choose whole and minimally processed foods whenever possible.

Avoid highly processed oils (corn, canola, sunflower, safflower, cottonseed, soy).

Use oils that are not processed (extra virgin olive, avocado, flaxseed).

Cook at home so you have control over what goes into your food,

Read ingredient lists.

Shop on the periphery of the grocery store. Most processed foods are on the interior shelves.