Swinging through the drive-thru or hopping into your favorite fast-food restaurant tends to happen more often than some would like to admit. According to the Food Institute’s analysis of data from the Bureau of Labor Statistics, millennials alone spend  of their budget’s food dollars on eating out.

In comparison to 40 years ago, the average American family now spends  their food budget on restaurant food. In 1977, just under  of family food budgets were spent eating outside the home.

While an occasional night of fast food won’t hurt, a habit of eating out could be doing a number on your health. Read on to learn the effects of fast food on your body.

Digestive and cardiovascular systems

Most fast food, including drinks and sides, are loaded with carbohydrates with little to no fiber. When your digestive system breaks down these foods, the carbs are released as glucose (sugar) into your bloodstream. As a result, your blood sugar increases. Your pancreas responds to the surge in glucose by releasing insulin. Insulin transports sugar throughout your body to cells that need it for energy. As your body uses or stores the sugar, your blood sugar returns to normal.

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This blood sugar process is highly regulated by your body, and as long as you’re healthy, your organs can properly handle these sugar spikes. But frequently eating high amounts of carbs can lead to repeated spikes in your blood sugar. Overtime, these insulin spikes may cause your body’s normal insulin response to falter. This increases your risk for weight gain, insulin resistance, and type 2 diabetes.

Sugar and fat

Many fast-food meals have added sugar. Not only does that mean extra calories, but also little nutrition. The American Heart Association suggests only eating of added sugar per day. That’s about six to nine teaspoons. Many fast-food drinks alone hold well over 12 ounces. A  of soda contains 8 teaspoons of sugar. That equals 130 calories, 39 grams of sugar, and nothing else.

Trans fat is manufactured fat created during food processing. It’s commonly found in:

fried pies

pastries

pizza dough

crackers

cookies

No amount of trans fat is good or healthy. Eating foods that contain it can increase your LDL(bad) cholesterol, lower HDL (good) cholesterol, and increase your risk for type 2 diabetes and heart disease.

Restaurants may also compound the calorie-counting issue. In one , people eating at restaurants they associated as “healthy” still underestimated the number of calories in their meal by 20 percent.

Sodium

The combination of fat, sugar, and lots of sodium (salt) can make fast food tastier to some people. But diets high in sodium can lead to water retention, which is why you may feel puffy, bloated, or swollen after eating fast food.

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A diet high in sodium is also dangerous for people with blood pressure conditions. Sodium can elevate blood pressure and put stress on your heart and cardiovascular system.

According to one study, about  of adults underestimate how much sodium is in their fast-food meals. The study surveyed 993 adults and found that their guesses were six times lower than the actual number (1,292 milligrams). This means sodium estimates were off by more than 1,000 mg.

Keep in mind that the American Heart Association recommends adults eat no more than  of sodium per day. One fast-food meal could have half your day’s worth.

Respiratory system

Excess calories from fast-food meals can cause weight gain. This may lead toward obesity.

Obesity increases your risk for respiratory problems, including asthma and shortness of breath. The extra pounds can put pressure on your heart and lungs and symptoms may show up even with little exertion. You may notice difficulty breathing when you’re walking, climbing stairs, or exercising.

For children, the risk of respiratory problems is especially clear. One  found that children who eat fast food at least three times a week are more likely to develop asthma.

Central nervous system

Fast food may satisfy hunger in the short term, but long-term results are less positive. People who eat fast food and processed pastries are  more likely to develop depression than people who don’t eat those foods or eat very few of them.

Reproductive system

The ingredients in junk food and fast food may have an impact on your fertility. One  found that processed food contains phthalates. Phthalates are chemicals that can interrupt how hormones act in your body. Exposure to high levels of these chemicals could lead to reproductive issues, including birth defects.

Integumentary system (skin, hair, nails)

The foods you eat may impact your skin’s appearance, but it might not be the foods you suspect. In the past, chocolate and greasy foods like pizza have taken the blame for acne breakouts, but according to the , it’s carbohydrates. Carb-rich foods lead to blood sugar spikes, and these sudden jumps in blood sugar levels may trigger acne.

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Children and adolescents who eat fast food at least three times a week are also more likely to develop eczema, according to one . Eczema is a skin condition that causes irritated patches of inflamed, itchy skin.

Skeletal system (bones)

Carbs and sugar in fast food and processed food can increase acids in your mouth. These acids can break down tooth enamel. As tooth enamel disappears, bacteria can take hold, and cavities may develop.

Obesity can also lead to complications with bone density and muscle mass. People who are obese have a greater risk for falling and breaking bones. It’s important to keep exercising to build muscles, which support your bones, and maintain a healthy diet to minimize bone loss.

Effects on society

Today, more than  are considered overweight or obese. More than one-third of children ages 6 to 19 are also considered overweight or obese. The growth of fast food in America seems to coincide with the growth of obesity in the United States.  (OAC) reports that the number of fast food restaurants in America has doubled since 1970. The number of obese Americans has also .

Despite efforts to raise awareness and make Americans smarter consumers, one found that the amount of calories, fat, and sodium in fast-food meals remains largely unchanged. As Americans get busier and eat out more frequently, it could have adverse effects for the individual and America’s healthcare system.

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