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Secret Side Effects of Eating Fast Food, Says Science

Fast food can affect your body negatively in more ways than one
FACT CHECKED BY Olivia Tarantino

Most of us are aware that aside from it being affordable, quick, and accessible that fast food doesn't have many redeeming qualities to its name. In fact, I think we can easily say that the negatives outweigh the positives.

Fast food began as a way to have convenience, and it took off in popularity in the 50s and 60s when more and more people were driving. But since then it has become one of the leading causes of obesity and heart disease in America, and its dangerously high levels of added sugars and saturated fats are keeping us addicted and coming back for more.

While we are aware of these unhealthy qualities of fast food, there are still some lesser-known side effects that not as many people know. Read on for some of the secret side effects of eating fast food, and for some healthy food options make sure to read The 7 Healthiest Foods to Eat Right Now.


It might affect your insulin levels

fast food

According to a 2018 report from The American Journal of Lifestyle Medicine, fast food products are absorbed into our bloodstream at a much faster rate than other foods. When we eat something highly processed, it sends a shocking amount of glucose to our bloodstream instantly and creates what's known as a "rapid insulin response."

Compare this to something that enters our bloodstream over the course of a few hours (the report uses high-fiber beans as an example), where glucose slowly enters our bloodstream and therefore doesn't require a lot of insulin at once.

This report also mentions that products with a lot of processed white flour, like white bread, cakes, and processed baked goods, contain something called advanced glycation end products (AGEs). A buildup of these in the bloodstream, especially when paired with rapid insulin response, has been known to lead to diabetes and other chronic diseases.

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It might damage your skin

fast food burger

Fast food can also have a negative impact on your skin. According to a report in Cosmetic and Investigational Dermatology, a Western diet of fast food, processed foods, and higher levels of added sugar has been linked to an increase in acne. And one of the main reasons for this is the increase in insulin activity that occurs when we eat junk food.

This report notes that there are actually societies that exist completely acne-free, like certain areas of Iceland, Papua New Guinea, and Brazil, and what these areas have in common is that they live off of a mostly Paleolithic diet.

Now we of course have to take other factors into account when it comes to acne, such as lifestyle and genetics, but our diet plays a large role.

Not only has fast food been known to lead to more acne, but several studies have shown that it can lead to harsher skin conditions. For example, a 2013 report on children and adolescents found that those who ate fast food three times a week or more had an increased risk of severe eczema. And although this study didn't cover the effects on adults, more research is being done.

RELATED: Ugly Side Effects of Eating Fast Food Every Day, According to Experts


You can increase your risk of disease

fast food

Sadly as affordable and delicious as fast food may be, it has been proven to increase the risk of chronic disease when consumed on a regular basis.

According to a review from Health Promotion Perspectives, the list of potential disease-related side effects of fast food consumption is extensive. The list includes things like abdominal weight gain, chronic inflammation, higher cholesterol, and increased risk of cardiovascular disease and diabetes.

RELATED: Foods That Can Decrease Your Diabetes Risk, Says Dietitian


Your mental health may take a plunge

fast food ice cream

Regular consumption of fast food might actually have an effect on our mental health. A study from The International Journal of Environmental Research and Public Health found that pro-inflammatory diets (which include fast food) have been linked to a greater risk in depression, especially for women and those who fall under the category of obese.

There are multiple factors at play here, with one being the high levels of trans fats and processed carbohydrates in fast food. According to Public Health Nutrition, trans fatty acids are known to lead to cardiovascular disease, chronic inflammation, and high cholesterol, which are all factors that can increase our risk of depression.

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Samantha Boesch
Samantha was born and raised in Orlando, Florida and now works as a writer in Brooklyn, NY. Read more about Samantha