How Quitting Smoking Affects Your Metabolism

Quitting smoking is often linked to weight gain, as cigarettes are appetite suppressants and nicotine speeds up your metabolism. However, with strategic planning and healthy food choices, you can manage any post-smoking metabolism drops.

Read more: Smoking Cigarettes: A Prime Risk Factor for Heart Palpitations

"In a nutshell, when you smoke, the nicotine in the tobacco makes your heart beat faster, which speeds up your metabolism," says Nikola Djordjevic, MD, a family physician and medical advisor at HealthCareers. "Smoking also triggers the release of dopamine, a chemical in your brain that is associated with feelings of pleasure and well-being."

In addition, smoking is a known appetite suppressant, and it can also alter your sense of smell, which can make certain foods less appealing.

The dopamine spike in your brain's reward circuit caused by nicotine intake is what gives smokers a brief euphoric feeling and what makes smoking addictive, despite the health risks, says the National Institute on Drug Abuse. Plus, nicotine withdrawal symptoms include irritability, feeling depressed or anxious, disturbed sleep, an increase in appetite and cravings.

Smoking has been linked to a number of adverse health effects, including heart disease, stroke, lung cancer, diabetes and chronic obstructive pulmonary disease (COPD), according to the Centers for Disease Control and Prevention (CDC). The CDC estimates that, in the U.S., cigarette smoking is responsible for more than 480,000 deaths a year and that more than 16 million Americans have a disease caused by smoking.

If you're a smoker who wants to stop, the Cleveland Clinic suggests making a specific plan: Assess why you smoke, when you smoke and where you smoke, pick a date to stop smoking, make a list of reasons for quitting, consult with a doctor about aids like nicotine patches and think up a number of things you can do instead of smoking when you feel the urge.

Examples of behaviors that can replace smoking include chewing gum, drinking a glass of water, texting a friend or working on a crossword puzzle.

"When you quit smoking, your heartbeat will slow down to normal levels, along with your metabolism," Dr. Djordjevic says. "That in itself can contribute to weight gain when you quit smoking, since your body will digest and absorb food slower than before. On top of that, smoking reduces appetite, so smokers tend to eat less than nonsmokers. Once you quit smoking, you will be eating more and digesting it slower, which will lead to weight gain."

To help manage weight gain, "you must engage in some physical activity after you quit smoking," Dr. Djordjevic says. "A brisk 20-minute walk once a day will do the trick if you are consistent and committed. However, some patients prefer to enroll at a gym or join a sports team, which helps motivate them to get some exercise."

According to the Mayo Clinic, it's not inevitable that you'll gain weight once you quit smoking, provided you commit to regular exercise and nutritious, filling food choices. Mayo recommends keeping healthy snacks on hand, like fresh fruits and veggies, yogurt and air-popped popcorn. You can also consult with a registered dietitian to help with meal planning and weight-loss strategies.

The Cleveland Clinic says that sticking to regular, healthy meals can help curb any tendencies to overeat. Furthermore, if you used to smoke a cigarette after a meal before you quit smoking, the clinic recommends trying out new post-meal rituals like walking around the block or brushing your teeth.

"Even if you do gain a few pounds, the health benefits of quitting tobacco will outweigh them," the Cleveland Clinic says.

Read more: How Soon After You Quit Smoking Can You Start to Exercise?