What Really Happens to Your Body When You Stop Eating Fast Food

Fast food has its place in life — sharing a pizza with friends can bring joy, for example, regardless of the nutrients it's giving you.

But cutting back on or removing fast food from your diet has its benefits, too. “Fast food isn’t just about calories — it’s about what it replaces,” says Erin Jowett, RD, an integrative dietitian at Integrative Weight and Wellness in Salem, Massachusetts. The more fast food in a diet, the fewer opportunities there are to nourish your body with nutrient-dense foods and the fiber, antioxidants, and phytonutrients that lower inflammation and support your metabolism, Jowett says.

Here’s how quitting fast food can positively impact your health, according to experts.

Removing fast food from your diet can meaningfully improve gut health, Jowett says, since it makes way for more gut-friendly options. “Fast food and ultra-processed foods are typically low in fiber, polyphenols, and antioxidants — all of which feed beneficial bacteria,” she explains. “They’re also high in refined oils, emulsifiers, and additives that can damage the intestinal barrier and promote inflammation.”

Put down the french fries and get more energy? While it’s a little more complex than that, Jowett confirms many people notice better, more stable energy when they cut down on fast food.

“Fast-food meals often contain large amounts of added sugars — especially from buns and sugar-sweetened beverages,” says Akhaphong. All that sugar causes repeated spikes in insulin, which can raise the risk of insulin resistance. “Insulin resistance occurs when the body’s tissues become less responsive to insulin, the hormone responsible for helping lower blood sugar,” Akhaphong explains. The result: more sugar flowing in the bloodstream.

Fast food’s low fiber is another factor in the blood sugar equation. Fiber slows down the absorption of glucose, helping steady your blood sugar. But foods like burgers and chicken nuggets tend to be low in fiber. By choosing home-cooked meals over fast food, you have more control over your fiber intake, supporting blood glucose control.

Although removing fast foods from your diet alone won't necessarily make you lose weight, it can contribute to your weight loss goals. “Fast-food meals are often high in calories, fat, and added sugars while offering little nutritional value — making them a challenge for weight management,” says Akhaphong.

Although research in this field is still growing, more recent studies show that your diet can affect your mood and cognition. “We now understand that mental health is closely tied to diet quality and the gut-brain connection,” says Jowett.

It’s totally normal to sometimes crave something salty, high-carb, or high-fat. “Cravings are often rooted in biology, not lack of willpower,” says Jowett. So don’t beat yourself up if you answer the siren song of the drive-through on occasion. Akhaphong suggests following an “80/20” approach to eating — watching your diet carefully around 80 percent of the time and giving yourself more leeway around 20 percent of the time.

That said, there are also ways to manage (or even prevent) cravings for fast food. Try these tips.

• Don’t skip meals. “Long fasting windows can trigger strong reward-driven eating later,” says Jowett. Eating at regular intervals can keep you off the cravings path.
• Make the best choice on the menu. If fast food is seriously calling your name, consider opting for a healthier choice on the menu. “For example, choosing a grilled chicken sandwich instead of fried, or swapping fries for a side salad can reduce calories, saturated fat, and added sugars,” says Akhaphong.
• Prioritize protein and fiber. To keep from getting ravenous, build meals and snacks around these two nutrients. “These slow digestion and balance hunger hormones like ghrelin and GLP-1,” says Jowett.
• Identify emotional triggers. Sometimes our emotions are the driver behind cravings. Get savvy about the situations that tend to trigger cravings for high-salt or high-fat foods — and try soothing these stressors with healthy coping tactics like deep breathing or exercise.
• Stay hydrated. Dehydration and low electrolyte intake can mimic salt cravings, Jowett says. Staying hydrated throughout the day can help.

• Cutting back on fast food makes room for other, more nutritious foods.
• Adding more healthy items like fruits, vegetables, lean proteins, and unsaturated fats to your diet can have a lasting positive impact on numerous areas of health, from lower risk of heart disease to improved mental health.
• Keep fast-food cravings at bay by prioritizing protein and fiber, staying hydrated, and not going too long between meals.