French fries could easily be considered America’s signature dish. As stated by the USDA, over one-third of the potatoes cultivated in the U.S. are transformed into frozen french fries, with the typical American eating nearly 35 pounds of fries annually (according to the NOAA). It’s understandable, given their appeal: crispy, hot, and perfectly seasoned, they are tough for many to resist.
Occasional indulgence is harmless, but frequent consumption poses significant health risks. Consuming french fries daily is highly detrimental. Their simple carbohydrates, saturated and trans fats, and sodium severely impact the body’s systems, including the skin, heart, and digestive system. Regularly indulging in this fried treat can dramatically raise the likelihood of developing severe chronic conditions, such as obesity, type 2 diabetes, and heart disease, all of which heighten the risk of premature death. It’s surprising how something as unassuming as a fry can be so perilous.
You’ll gain weight
One medium portion of french fries from a major fast-food chain contains 427 calories (source: MyFoodData). The average person requires around 2,000 calories daily to maintain their weight, and that single serving constitutes nearly a quarter of the daily intake. Given that french fries typically accompany a burger or another high-calorie item, you could potentially consume about 75% of your daily calorie needs in just one meal. Regularly exceeding your calorie requirements is a primary factor in weight gain and obesity. Excess energy consumption that the body doesn’t immediately utilize is stored as fat. The more surplus energy consumed, the more fat is accumulated.
The high caloric content of french fries mainly stems from their fat content. Each gram of fat provides 9 calories, which is more than double the calories provided by protein or carbohydrates, which offer 4 calories per gram. Consequently, for the same food weight, you’re consuming more than double the calories. That medium serving contains 20 grams of fat, translating to 180 calories from fat. Contrary to popular belief, fat itself doesn’t cause weight gain. However, consuming many high-calorie fatty foods makes it easy to exceed calorie needs, leading to weight gain.
Your blood sugar will be unstable
Most of the remaining calories in that portion of fries come from carbohydrates. Carbohydrates often receive negative attention, although not all are harmful. However, the carbs in french fries are problematic.
Processed white potatoes are a source of simple carbohydrates that the body quickly digests, rapidly releasing glucose, a form of energy, into the bloodstream. The glycemic index measures how carbohydrates affect blood sugar levels. On a scale from 1 (least effect) to 100 (greatest effect), french fries score a 75, designating them as a high-glycemic food (source: Glycemic Index Guide).
The issue with high-glycemic foods is that they cause erratic blood sugar levels. This can lead to significant spikes and rapid drops, making it challenging to maintain consistent energy levels. High-glycemic foods may provide a brief energy boost, but blood sugar levels decline quickly, leaving you feeling fatigued. Blood sugar fluctuations can lead to food cravings, overeating, and weight gain. Regularly consuming high-glycemic foods can result in insulin resistance and type 2 diabetes.
Your blood pressure will skyrocket
French fries wouldn’t be nearly as tasty without several shakes of salt, but that’s one of the reasons they’re so unhealthy. Salt contains sodium, an essential electrolyte mineral that your body requires in small amounts for proper function. However, excessive sodium intake can lead to problems. Too much sodium in the bloodstream causes fluid retention in the blood vessels, increasing the volume within these vessels, which raises blood pressure. High blood pressure significantly increases the risk of heart disease, heart attack, stroke, kidney disease, osteoporosis, and stomach cancer. At best, excess sodium causes water retention that can result in bloating, puffiness, and weight gain.
To avoid these health issues, the American Heart Association advises adults to limit daily sodium intake to 1,500 milligrams. A medium serving of fast-food french fries contains 311 milligrams of sodium. By itself, that’s not an excessive amount — about 20% of the daily recommended limit. However, these fries are likely accompanied by other high-sodium foods. And that’s just one meal. Note that if you’re consuming a large serving daily, it contains over 400 milligrams.
Sodium accumulates more quickly than you might realize, especially if you consume many processed foods like french fries. The AHA reports that the average American consumes 3,400 milligrams of sodium daily, more than double the recommended limit.
Your cholesterol levels will rise
Vegetable oil is typically used to fry french fries. That doesn’t sound too bad; after all, it comes from vegetables. However, many restaurants use hydrogenated vegetable oils, which are vegetable oils that have had hydrogen added to enhance shelf stability. Hydrogenated oils are a source of trans fats, a harmful type of fat that elevates levels of low-density lipoprotein (LDL) and decreases levels of high-density lipoprotein cholesterol (HDL). LDL is the “bad” cholesterol that accumulates in the arteries and causes blockages. HDL is a “good” cholesterol that helps remove bad cholesterol from the arteries and lowers the risk of adverse effects. Consuming trans fats increases the risk of heart disease and stroke and may also elevate the risk of type 2 diabetes. Trans fats are so detrimental that the FDA has declared them unsafe for human consumption.
French fries may also be fried in animal fats such as lard. Animal fats may contain traces of naturally occurring trans fats, but not enough to cause problems. However, animal fats are high in saturated fat. Saturated fat is not as harmful as trans fats but is still not beneficial. Consuming excessive saturated fat from daily french fry intake can increase bad cholesterol and elevate the risk of developing heart disease.
You’ll have digestive problems
If you consume many fatty foods like french fries daily, you may experience stomach discomfort. Fat is challenging for the body to digest, and eating a large amount at once can cause digestive issues such as gas and bloating. A fatty diet can also result in fat accumulation in the colon and small intestine, leading to excess fluid production in the colon that can cause diarrhea.
However, the side effects of a high-fat diet aren’t just short-term. According to research, a high-fat diet can alter the microbiome, the collection of good and bad bacteria in the gut (source: BMJ). An imbalance in these bacteria can lead to a condition called leaky gut, where the intestinal lining becomes more permeable. This may allow toxins, partially digested food, and other substances to leak into the bloodstream. A damaged intestinal lining has been associated with several gastrointestinal conditions, including Crohn’s disease, celiac disease, and irritable bowel syndrome.
Your brain won’t work well
Your brain utilizes 20% of the calories you consume, even though it constitutes only 2% of your body weight. A healthy diet is essential for brain health. Nutritious foods provide your brain with the energy it needs to remain alert and productive. Conversely, a poor diet rich in processed foods like french fries may leave your brain undernourished.
French fries are a high-glycemic food, meaning they are prone to causing rapid blood sugar spikes and drops. Initially, you might feel more energetic and alert as the simple carbs flood your bloodstream, but this is short-lived. Your blood sugar will soon plummet, leaving you tired and foggy-headed.
Fat can also contribute to brain fog and cognitive issues. Research has shown that individuals consuming a high-fat diet perform worse on cognitive tests than those who don’t (source: National Institutes of Health). Additionally, individuals with a diet high in saturated and trans fats have an elevated risk of developing Alzheimer’s disease.
Your bones may weaken
You are likely aware that a poor diet lacking in bone-strengthening nutrients like calcium is a common cause of weak and fragile bones. A lesser-known cause is a diet high in sodium. Sodium helps regulate calcium loss in the urine. High sodium intake can lead to excess urinary excretion of calcium. Over time, this can result in reduced bone mass density and weaker bones. Calcium losses can also contribute to kidney stones, osteoporosis, muscle mass loss, high blood pressure, and stroke.
The suggested daily sodium limit is less than 2,300 milligrams per day, equivalent to about one teaspoon of salt. If you’re generously salting your daily fries and consuming sodium from other foods, it’s easy to exceed the recommended limit. The American Heart Association recommends an even lower daily intake of no more than 1,500 milligrams of sodium to significantly reduce the risk of osteoporosis, high blood pressure, heart disease, stroke, kidney issues, and cancer.
Your skin won’t look its best
Perhaps you’ve heard that consuming fatty, oily foods causes oily skin and acne. According to Yale Scientific, this is a myth. Oil from food doesn’t directly appear on your skin. However, french fries can indirectly cause skin issues in several ways.
As a high-glycemic food, fries cause blood sugar fluctuations that increase inflammation and stimulate sebum production in your body. Both factors can contribute to acne flare-ups. According to the American Academy of Dermatology Association, some studies indicate that individuals on a low-glycemic diet experience fewer breakouts. Inflammation can also contribute to other skin issues like psoriasis and eczema, as noted in a review in the International Journal of Molecular Sciences.
Fried foods are also high in omega-6 fatty acids. While some of these fats are necessary, excessive intake can be harmful, especially if your omega-3 fatty acid intake is low. This imbalance can lead to inflammation, affecting every organ, including the skin. The American diet, which includes many fried and processed foods, often provides an omega-6 to omega-3 ratio as high as 30 to 1. However, according to Riverview Health, the ideal ratio is 4 to 1. Consuming french fries daily makes achieving this balance challenging.
You might get sick more often
It’s well established that a healthy diet is linked to a robust immune system. Consuming adequate amounts of essential vitamins, minerals, and antioxidants supports essential immune responses. Conversely, a diet rich in processed and fried foods can compromise the immune system. High omega-6 fatty acid levels in processed foods cause systemic inflammation, weakening the immune response and increasing the risk of immune dysfunction and disease. Deep frying and other high-temperature cooking methods produce molecular compounds known as advanced glycation end products (AGEs). According to a review in the Journal of Immunotoxicology, AGEs may promote inflammation and cellular dysfunction while negatively affecting the gut microbiome, the collection of beneficial and harmful bacteria in the gut that influences immune health.
Salt can also impact the immune system. According to a review in Cell Proliferation, high salt intake can affect immune cell function. It can also raise tissue sodium levels, influencing the body’s immune response and the development of disease pathology in conditions such as hypertension, multiple sclerosis, infections, and cancer.
You’ll have less energy
Processed foods high in fat and sodium are energy drainers. High-glycemic foods like french fries can cause significant blood sugar disruptions. After an initial spike, blood sugar levels drop, leaving you fatigued.
High-fat foods can also impact energy levels, causing fatigue after consumption. A study in Physiology & Behavior found that a high-fat meal left participants feeling considerably more fatigued compared to a high-carbohydrate meal, with the effects being most pronounced three hours post-meal. Regular lunchtime french fries might be why you’re tempted to nap at your desk mid-afternoon.
Salty foods can also sap energy by disrupting sleep. Dr. Sandra Darling, DO, MPH, explained to the Cleveland Clinic that excessive sodium consumption later in the day can elevate blood pressure and cause fluid retention, both of which can lead to restless sleep and morning fatigue. Adequate, restful sleep is crucial for maintaining steady energy levels throughout the day. If you’re consuming french fries for dinner every night, restful sleep might be elusive.
You might feel anxious and depressed
While french fries may serve as a comfort food, studies suggest they could worsen your mood. A study in the Proceedings of the National Academy of Sciences of the United States of America found that individuals consuming higher amounts of fried foods, particularly fried potatoes, had a 7% increased risk of anxiety and a 12% increased risk of depression. Researchers attribute this to exposure to acrylamide, a chemical formed during frying. Preliminary animal studies showed that zebrafish exhibited anxiety and depression symptoms when frequently exposed to acrylamide.
Additionally, high-glycemic foods have been linked to mood disorders due to their effects on blood sugar, according to the University of Michigan School of Public Health. Blood sugar fluctuations can result in mood changes and nervousness, particularly in individuals with existing mental health conditions.
Systemic inflammation has been associated with poor mental health. Consuming many fried foods can elevate inflammation levels throughout the body, potentially leading to depression and anxiety, as discussed in a review in BMC Medicine.