How Processed Foods Can Affect Your Health

Hot Dog

Verywell / Alexandra Shytsman

Recently, I was meeting a friend at a park over lunch, and I noticed a really disturbing trend. Almost everyone there was opening a package or box for their lunch.

As you are probably aware, multiple concerns have been raised about processed foods, including the abundance of processed foods and the dangers they pose. In fact, a recent study performed by researchers at the University of Chapel Hill found that more than 60% of the food purchased annually in America is highly processed. As evidence mounts linking over-consumption of these products to major health consequences, highly processed foods are becoming a concerning trend.

Some basic food processing is necessary to ensure the safety of perishable items, such as fresh meat or dairy. The concern lies with products considered to be highly processed.

Examples of Processed Foods

Processed foods are the convenience items that dominate the center aisles of your typical grocery store:

  • ready-made meals
  • canned goods
  • cookies
  • chips
  • soda
  • candy and other packaged items
  • bacon
  • sausages
  • hot dogs
  • lunch meat
  • cheese slices or spreads

These types of foods constitute the majority of the calories consumed on a regular basis for the average American family. Avoiding processed foods altogether may be impossible, but understanding why consuming too many may be detrimental is an important first step to improving your health. For starters, these products typically contain increased amounts of salt, sugar, or fat—all of which do not support health when consumed in excess.

Highly processed foods are also typically chemically treated with additives or preservatives to improve their taste, texture, or to extend shelf-life. An easy way to identify any processed food is to take a look at the label; if there is a laundry list of ingredients with unrecognizable, complicated names it is safe to say it's processed food.

Here are six ways overconsumption of processed food could be affecting your health.


It is well known that sugar contributes to obesity, which can then lead to a host of other chronic diseases. Highly processed foods are often loaded with added sugar but don’t be fooled if the word “sugar” doesn’t actually appear on the label. There are as many as 50 different words used to list types of sugar added to processed foods. The most common names are corn syrup, fructose, glucose, sucrose, malt or maltose, honey, molasses, or nectar.

Known as “empty calories,” any type of sugar, including those hidden or disguised varieties, adds no nutritional value except carbohydrates and calories and in fact, may encourage your body to consume even more calories.

Consumption of sugar triggers a sense of pleasure and craving within the brain comparable to that associated with drug addiction. This explains why it is so hard to resist seconds after indulging in a sweet treat—and why we might experience subconscious cravings for other highly processed meals and snacks.

So, how much sugar consumption is too much? The 2020-2025 Dietary Guidelines for Americans recommends added sugars should be limited to no more than 10% of daily calories. This equals about 12 teaspoons of sugar per day, which sounds pretty generous until you put into perspective that the average can of soft drink contains about 10 teaspoons alone. 

Metabolic Syndrome

As if obesity were not bad enough, processed food consumption is also linked to metabolic syndrome, which is defined as a group of risk factors that can lead to heart disease and type 2 diabetes. Metabolic syndrome is diagnosed when any three or more of the following five risk factors are present:

  • Increased waistline with abdominal obesity
  • Elevated triglycerides, or needing medication to lower triglycerides
  • Low HDL (healthy) cholesterol levels, or needing medication due to low HDL levels
  • High blood pressure, or needing medication to treat high blood pressure
  • High fasting blood glucose or needing medication due to high fasting blood glucose

When refined carbohydrates are consumed in excess quantities, the sugars must be stored in the body—typically as fat—and may lead to several metabolic consequences. An example of these types of metabolic occurrences is frequent spikes in blood glucose levels requiring insulin to stabilize. Over time, this can lead to insulin resistance, as well as increasing the levels of ​triglycerides in the blood. The cumulative effects of these metabolic disturbances can raise the risk of developing heart disease and diabetes.​

Inflammatory Bowel Disease

Processed foods can also play a role in the development of inflammatory bowel disease, also known as Crohn’s disease or ulcerative colitis. This time, the culprit is a type of chemical additive called emulsifiers, which are used to extend shelf life and help hold the shape or texture of foods. They are found in nearly every processed food product, including breads, peanut butter, cake mixes, salad dressings, sauces, yogurt, pudding, processed cheese, ice cream, and desserts.

It may be surprising to know that the emulsifiers used in processed food are similar to those also found in your household soaps or detergents. This is because the primary function of an emulsifier is to allow water and oil to stay mixed, whether it’s for the purposes of removing grime and stains, or for holding together food substances that normally would separate.

In a recent study, mice who were fed a diet simulating the type and quantity of typically consumed emulsifiers found in processed foods were found to have changes observed in their gut bacteria that triggered several health conditions including the ones already discussed—obesity and metabolic syndrome—as well as inflammatory bowel disease. The reason for this connection is because the bacteria affected compromise the mucus protective layer that usually separates microbes from the intestinal wall, similar to how a detergent works to remove dirt, which led to an inflammatory response and increased the incidence of these diseases. 

Autoimmune Diseases

Autoimmune diseases are triggered when the body’s immune system goes haywire and attacks its own cells. There are over 100 different autoimmune diseases, but the more common ones are type 1 diabetes, lupus, multiple sclerosis, rheumatoid arthritis, Crohn’s disease, and Hashimoto’s thyroiditis. In these diseases, the immune system confuses healthy cells as unhealthy and prompts an attack on the body it is meant to protect.

It is estimated that 70% of your immune system is located in your gut. This is not surprising when you consider all of the environmental toxins that travel through your digestive tract from start to end. Your intestinal tract is lined with a special layer of cells called epithelial cells, whose function is to serve as a protective membrane. The intestinal epithelial cells are joined together by tight junctions, which helps to keep them bonded together and strengthens the defense barrier against bacteria, toxins, and other harmful antigens. But when these tight junctions become compromised, they weaken the body’s defense and can allow the exposure of harmful antigens into the body by increasing intestinal permeability. This is termed “leaky gut” and is currently a hot topic in medical research. 

Research has shown that seven common additives abundantly found in processed foods can damage the tight junctions, making them weaker and increasing intestinal permeability. This, in turn, opens up the door for toxins to harm the body, which can raise the likelihood of developing an autoimmune disease. The seven additives identified are glucose, salt, emulsifiers, organic solvents, gluten, microbial transglutaminase, and nanoparticles—all of which are commonly used in processed food products.

Colorectal Cancer

Processed foods can also increase the risk of developing colon cancer. This time, the culprit is processed meats, which include lunch meat, bacon, sausage, hot dogs, and beef jerky or any other meat product that has been chemically treated in order to stay preserved. The risk also includes consumption of red meat such as beef or pork.

Eating as few as 50 grams of processed or red meat daily, which is roughly the equivalent of a small hot dog or two slices of bacon, has been found to raise the risk of colorectal cancer by 18%. It is believed that the risk comes from either the chemicals used to preserve these meats or the cooking process by which they are preserved, both of which are associated with exposure to carcinogenic compounds. 

Anxiety and Depression

If you’re not compelled to take a closer look at processed food consumption yet, here is another health risk to consider. Diets high in processed foods are also linked to increased rates of anxiety and depression. One theory is that exposure to those added sugars can wreak havoc in your gut, where the majority of serotonin production occurs.

Serotonin is an important mood stabilizer, and when a diet includes the chemical additives common in processed foods, it can adversely affect the body’s ability to maintain healthy levels of serotonin.

In addition, remember that all those added sugars cause a spike in blood glucose and increased insulin production, which sets in a motion a roller coaster metabolic process that can result in hyperactivity followed by lethargy. Also, since those added sugars can become highly addictive, your body continually craves more, repeating this process over and over. 

A Word From Verywell

Overall, diets high in processed foods usually mean that less real food is consumed, which results in the body becoming deficient in other vitamins and minerals that are needed to support your mood, emotional health, and overall wellbeing. Although it is virtually impossible to completely eliminate processed food from our daily diets, it is good to be mindful of just how much you are eating. This awareness can help to create a healthier lifestyle and help with many medical ailments. I always tell my patients that food can be a medicine or a toxin. Make your diet work for you not against you.

13 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Kenneth Brown, MD
Kenneth Brown, MD, is a board-certified gastroenterologist and doctor of internal medicine. Dr. Brown specializes in Irritable Bowel Syndrome, colon cancer screening, and gastroesophageal reflux disease.