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Ugly Side Effects of Eating French Fries, According to Science

Your favorite greasy side impacts your brain, weight, immune system, and even your lifespan.

Sure, they're among the tastiest foods you can eat, but if you're eating a diet high in fries on a regular basis, don't expect to avoid the consequences in the near and long-term. In the case of the latter, at least one downfall stands out: According to a study of nearly 4,500 adults published in The American Journal of Clinical Nutrition, feasting on french fries more than twice per week could double your risk of early death. For perspective, know that researchers pointed to the oils the potatoes were fried in as the driving force behind the enhanced health risk—and less the potatoes themselves. The researchers were not able to link potatoes prepared by other means to a greater risk of early death.

Regardless, if that's not enough to convince you to reduce your intake of deep-fried potatoes, read on, because we've compiled just some of the uglier side effects right here. And for more science-backed reporting that can have a major impact on your life, make sure you're aware of  Ugly Side Effects of Drinking Alcohol Every Day, According to the Mayo Clinic.

Your Stomach May Start to Hurt

Woman suffering from stomach cramps on the sofa at home.

Given that fats are more slowly digested by the body than carbs and proteins—and given that they contain more calories as a result of how they're cooked—it's a good bet that your fries will sit in your stomach for much longer than if you were filling up on healthier food. As a result of this, according to a study published in the journal Ultrasound International Open, you'll have a greater chance of suffering through stomach pains. Other related side effects from your body's unique digestion of fried foods include nausea, diarrhea, bloating, and cramping. For more side effects of eating fries, be sure you're aware of What Eating Fried Foods Does to Your Body.

Your Brain Gets Foggy

brain fog

Given the fact that they're deep-fried in hydrogenated oils, fries come packed with a high amount of trans fat, which raises your bad cholesterol and lowers your good cholesterol. The profound effect of this is that you'll boost your heart disease risk. According to a 10-year study involving 1,600 elderly people in Japan and published in the journal Neurology, people with the highest levels of industrial trans fats in their blood were up to 75% more likely to develop Alzheimer's disease or dementia. This is one of the many reasons that French fries are not among The Best Foods for Your Brain.

Your Immune System Could Take a Hit

Woman having throat ache

According to a study published in the journal Current Opinion in Clinical Nutrition & Metabolic Care, eating a high-fat, greasy diet (which, if you're consuming lots of fries, you're definitely doing), you could be damaging your gut microbiome by boosting unhealthy bacteria and diminishing your body's healthier bacteria. Given the gut's role in helping inform your body's immune system, you could be exposing your body to sickness and disease.

You'll Increase Your Risk of Heart Disease and Stroke

mature man having heart attack at home

A study of roughly 150,000 military veterans conducted by researchers at the U.S. Department of Veterans Affairs and the Massachusetts Veterans Epidemiology Research and Information Center found that eating fried foods three times per week had a 7 percent greater risk of heart attack and stroke. If the study participants consumed fried foods every day, their risk doubled to 15 percent. "Our findings provide evidence for a dose-dependent association between fried food consumption and incidence [of coronary artery disease]," concluded the researchers.

 Ugly Side Effects of the American Diet, Say Dietitians

You'll Gain Weight

Man weighing himself on scale with shoes on

Fact: When foods are fried in fat, they become super calorie bombs. To provide just one example of backing evidence for the link between fries and your waistline—and, to be sure, there are many—a study published in The American Journal of Clinical Nutrition found that eating fried foods was directly linked to cases of obesity. This is one of several reasons why fries rank high among the 101 Unhealthiest Fast Foods on the Planet.

Read more healthy eating tips:

4 Major Effects Drinking Beer Has on Your Health, New Study Says

Surprising Side Effects of Taking Vitamin D Supplements After 50

Secret Side Effects of Eating Ginger, Say Dietitians

William Mayle
William Mayle is a UK-based writer who specializes in science, health, fitness, and other lifestyle topics. Read more about William
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