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Worst Habits That Destroy Your Immunity, Doctor Says

If you take care of your immune system, it will take care of you.
FACT CHECKED BY Emilia Paluszek

The human body does amazing things, and our immune response is a perfect example. Every day, all day long, our immune system is silently defending us from invaders, protecting us from disease, and even recognizing and destroying cancer cells before they can grow. On the other hand, when our immune system is overactive and reacts to harmless substances, we develop allergies and autoimmune diseases. Everybody wants a strong and healthy immune system, and over the past 2 years with the Covid 19 pandemic, the importance of a well-functioning immune system has become even more apparent. I am a physician, board-certified in Emergency Medicine and Lifestyle Medicine, and I help people lose weight and optimize their lifestyle, so they can strengthen their immune system, prevent disease, and live a longer and healthier life. Read on to find out more—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.


Skimping on Your Sleep

woman sleeping peacefully in bed with her dog

Sleep is critical for our immune system to function optimally, yet so many Americans, don't get enough. According to the CDC, 1 out of every 3 American adults gets less than the recommended minimum amount of 7 hours. Not only can a lack of sleep impair your ability to fight off infections, and then slow down your recovery, but there is also evidence that insufficient sleep and disruptions to your circadian rhythm can increase your risk for cancer, heart disease, and type 2 diabetes. Make sure to prioritize your sleep, and if you are having trouble sleeping, try limiting your screen time before bed, keeping your cell phone out of your bedroom at night, and avoiding alcohol, caffeine, and sugar in the evening.


Not Eating Enough Nutrients

nutrient rich foods

Micronutrients are the essential building blocks for your body to function properly, and eating a nutrient poor diet will inhibit your ability to fight off infections and for your body to heal. The best way to eat a diet rich in nutrients is to eat at least 5 servings of fruits and vegetables a day, which will provide a range of vitamins, minerals, phytonutrients, and antioxidants. (More servings of fruits and vegetables is even better). Eating this way will also provide fiber, which has numerous other health benefits, including supporting the microbes in your gut that are closely linked with your immune system.


Being Sedentary

Woman sitting on bed looking at phone bored and in a bad mood

An inactive lifestyle is detrimental to our health in multiple ways. Not only does increased sedentary time promote inflammation, weight gain and chronic disease, but it also negatively impacts our body's ability to fight infections. In contrast, a regular routine of moderate physical activity has enormous benefits to both our physical and mental health and is believed to strengthen our immune system. Ideally, you should aim to get 30-60 minutes of moderate physical activity at least 5 times a week, but any amount of increased physical activity has benefits, even 10 minutes. Try taking a walk outside daily. Not only will this decrease your sedentary time, but it can also decrease your stress, and boost your vitamin D levels, which will all help your immune system.


Drinking Too Much Alcohol

alcoholic beverages

There are multiple reasons why excessive alcohol intake can impair the immune system. Drinking too much alcohol promotes inflammation. Alcohol intake interferes with our gut microbiome, which is closely linked to our immune system. Not only that, but binge drinking may temporarily reduce the amount of infection fighting cells in our blood, even after just one episode. For women, and men over 65, moderate drinking means drinking up to 1 drink per day. For men 65 and under, 2 drinks a day is considered moderate.


Putting Too Much Stress on Ourselves

Businesswoman tries to cope with nervous tension or anxiety

Stress increases the levels of cortisol in our body, which over time, promotes inflammation and drains our immune system. Stress can also deplete our lymphocytes, the body's virus fighting cells, which can make us more susceptible to viral infections. Some amount of stress in our life is inevitable, but it is possible to reduce our stress and better manage our stress by practicing mindfulness. Incorporating mindfulness based stress reduction techniques into your routine, such as yoga and meditation, can decrease stress, decrease your body's physiologic response to stress, and may actually boost your immune system.



girl in casual clothes smoking an electronic cigarette

Smoking is the worst habit for your immune system, for multiple reasons. Not only does smoking weaken your immune system, making your body more susceptible to infections and increasing your risk for developing cancer, but smoking cigarettes has also been linked to increasing the risk for autoimmune diseases such as rheumatoid arthritis. Inhaling smoke damages and paralyzes the cilia, the tiny hairs in your respiratory tract that are the first line of defense against infections, which explains why smokers are at an increased risk for colds and respiratory infections such as pneumonia. But even worse, the many chemicals in cigarette smoke interfere with the immune system's ability to function properly and make the body less effective at fighting disease. Quitting smoking is not easy, but it is the best thing someone can do for their health. 


What should someone do if they notice signs of immune system disorder?

happy doctor with patient

There are an abundance of products and supplements which all claim to boost the immune system. But in reality, living a healthy lifestyle is the best way to take good care of your immune system, so that it can function optimally. With a healthy immune system, you will be more capable of fighting off infections, be able to heal faster, and be reducing your risk for multiple chronic diseases. Bottom line, if you take care of your immune system, it will take care of you. And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Ritu Saluja-Sharma MD is a board-certified physician in Emergency Medicine and Lifestyle Medicine, an integrative health coach, and the founder of Head Heart Hands.

Ritu Saluja-Sharma, M.D.
Ritu Saluja-Sharma MD is a board-certified physician in Emergency Medicine and Lifestyle Medicine, an integrative health coach, and the founder of Head Heart Hands, a comprehensive wellness and weight loss program for businesses and individuals. Read more about Ritu