How Obesity Weakens The Immune System And Increases Your Risk Of Infection

29 Nov 2020

immunity Lifestyle obesity

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While you should learn to love yourself and be comfortable in your own skin, loving yourself also means taking better care of yourself. One of the best ways in which you can do this is by maintaining a healthy body weight. Aside from the fact that obesity and excess weight can increase the risk of various chronic disorders, the coronavirus pandemic has highlighted its impact on immunity. SARS-CoV-2 patients with a BMI over 40 have been found to face a 2.6 fold higher risk of mortality as compared to other patients (1).

Being obese means being abnormally overweight. Obesity is a health condition in which excess fat is accumulated in the body, increasing the weight of the person suffering from it makes them more susceptible to various diseases and health conditions. Here’s everything you need to know about the effects of obesity on immunity.

To understand the link between obesity and impaired immunity, we should first take a look at how healthy immunity works.

Understanding The Healthy Immune Response

Under normal circumstances, the immune system gets triggered when you are infected with a bacterial or viral pathogen. This causes inflammation, which is part of the “innate” immune response – the first defense.

Although this results in swelling and redness due to increased blood flow, this is part of the healthy response and a sign that your body’s fighting the infection. The inflammatory response is triggered by cytokines (type of protein), which are produced by macrophages or white blood cells.

As white blood cells fight off and overcome the foreign invader, inflammation subsides and things return to normal.

How Does Obesity Affect Immune Function?

Obesity is the result of excessive calorie intake, which is then stored as fat in the body. In obese individuals, the healthy immune response gets hijacked by fat cells. These fat cells are known as adipocytes and are now recognized as an active endocrine organ – organs that secrete proteins and chemicals (2). That’s because adipocytes can emit the same cytokines that white blood cells do.

When your body has too much fat content, it means that there are more adipocytes producing cytokines. This triggers inflammation and there can be no reduction in inflammation unless the number of fat cells is reduced. In other words, your body is now in a constant state of inflammation. This is why obesity is regarded as a disorder involving a state of ‘low-grade, chronic inflammation’ (3).

Ultimately, this constant state of alert for the immune system results in impaired immunity because the immune system does not respond to threats normally.

Obesity and Increased Infection Risk

When your immune system is compromised due to chronic inflammation caused by obesity, it makes you susceptible to a variety of infections. This increased risk has been documented in several studies.

During the H1N1 outbreak, which is now overshadowed by COVID, doctors in Spain noticed a disturbing trend. The number of overweight and obese patients in ICU wards was significantly higher and obese patients also tended to require longer hospital stays as compared to patients in the healthy weight group. Similar patterns have been observed in flu records studied by Canadian researchers (4).

With the current pandemic we are witnessing similar effects. A study that appeared in Endocrinology suggests that obesity causes a ‘hyperactive immune system response’, making it harder for the body to fight off the infection. The study authors also point out that ‘obesity-driven dysregulation of innate immune responses’ contributes to a higher risk of organ damage and impaired viral clearance in obese patients (5).

Obesity’s adverse effects on immunity are not limited to increased risk of infection. The chronic inflammation caused by obesity is also associated with a greater risk of conditions like heart disease and diabetes.

Now that the link between obesity and immunity is clear, it is imperative that we approach the obesity epidemic with greater urgency. At the same time, it’s important to remember that being skinny and having zero percent body fat isn’t healthy either.

Tips To Reduce And Control Obesity

Exercise regularly
Follow a healthy-eating plan
Opt for supplements that support weight loss such as Setu Lean Lite
Maintain a balanced diet
Know and avoid the food traps that cause you to eat unnecessarily
Monitor your weight regularly
Consume less processed and sugary foods
Eat more servings of vegetables and fruits

Elizabeth Bangera

Armed with an MSc. in Food, Nutrition, and Dietetics, Elizabeth wears many hats and is skilled in everything from weight loss to diabetes and cardiac care management.