Feb 072020

Two Sneaky Ways Junk Food Weakens the Immune System

Two Sneaky Ways Junk Food Weakens the Immune System

Junk Food is All Around Us

Junk food is the go-to food for many Americans. It is becoming a global staple, as the obesity rate continues to rise worldwide. What is it about junk food that has hooked millions of people – taste, convenience, price? Likely, it is a combination of all three. Food companies invest millions of dollars into research and development every year to study the driving influences of people and junk food to identify how to get them hooked.

Junk Food is Nothing But Empty Calories

Junk food is extremely high in calories and does not have any substantial nutritional value. It is low in nutrients like proteins, healthy fats, minerals, vitamins, and dietary fiber that are necessary for a variety of the body’s functions. Junk food includes both processed and fast food. Some of these items include bakery items, candy, soft drinks, snacks, pizza, French fries, potato chips, and ice cream, among others.

Junk food is nothing but empty calories and has a reputation for being unhealthy. It is commonly associated with chronic health conditions like obesity, atherosclerosis, heart disease, type-2 diabetes, and high blood pressure. These are some of the most prevalent health conditions in the U.S. and around the world.

Junk food is rich in added sugars, unhealthy fats, and salt (sodium), chemicals, and preservatives that reduce the immune system response. Reduced immune system responses make people more vulnerable to infections.

In this post, we look at a few ways junk food weakens immune system response, especially when eaten frequently.

Two Sneaky Ways Junk Food Weakens Immune System Response


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1. Junk Robs the Body of Important Vitamins and Minerals Needed for the Immune System Response

Consuming junk and fast food can lead to a deficiency of many nutrients in the diet. One such nutrient is vitamin C, which can be lacking in people who consume a lot of junk or fast food. Vitamin C and sugar have nearly identical compound structures; they both fight for entry into immune system cells. Consuming too much sugar could limit vitamin C’s access to immune system cells.

Vitamin C boosts immunity by promoting the differentiation and growth of B and T cells. It may also reduce the life span of infectious conditions, like the common cold. Better immune responses require the body to consume regular doses of vitamins, like vitamin C, antioxidants, and minerals, like zinc.

Adopting a dietary style that mainly consists of prepackaged food and fast-food restaurants leads to a reduced intake of vitamins, antioxidants, and zinc, causing increased inflammation in the body.

The Immune System Sees Junk Food as a Threat

A high sugar intake alters how white blood cells respond to bacteria. The high-[unhealthy]fat content in junk food is a predisposing factor to altered immunity, which results in an increased response despite not being needed. In other words, the body’s immune system is always fighting a “perceived” threat whether or not there is one.

Generally, when the body gets exposed to an infection source (e.g., a virus, pathogen, fungi, bacteria, or parasites), an intracellular complex called an inflammasome becomes activated and causes widespread inflammation. This inflammasome remains alert to detect any incoming infection source so the body can eliminate it as soon as it arrives.

However, persistent inflammasome release can disrupt the human body and its functions.

How does junk food play a role?

Junk food affects the body’s immunity by activating the inflammasomes, causing widespread inflammation in the body. Overconsumption of the unhealthy food causes the body to react like it is fighting a bacterial infection. According to Bonn University in Germany, when a person eats unhealthy and consumes mostly junk food, the body’s defense systems become more aggressive. This leads to inflammatory conditions such as type-2 diabetes and atherosclerosis.

Such aggressiveness does not get resolved immediately when the person starts consuming a healthy diet.

It will take time before the aggressiveness dies down and proper regulation can occur. This is because the innate immunity retains memories that keep the body in an attentive state. Generally, these immune cell memories fight secondary infections and protect the body. They are the result of epigenetic changes in the innate immune cells, known as innate immune training or reprogramming.

An unhealthy diet also forces this immune response and increases inflammation throughout the body. This can lead to chronic inflammation, and the persistent inflammatory condition promotes the development of type-2 diabetes and high LDL cholesterol.

Atherosclerosis is also possible as a result of chronic inflammation. This inflammation increases the size of atherosclerotic plaque, resulting in the likelihood of rupture of the plaque, and can lead to clots that increase the chances of a stroke or heart attack.

To summarize, an unhealthy diet promotes chronic inflammation.

3. Bonus: Junk Food Has Little to No Fiber

Junk food consists of refined and processed ingredients and is low in dietary fiber content, both of which lead to various problems. Dietary fiber may have a protective mechanism for the heart and may offer some protection against type-2 diabetes. Some studies have also shown that fiber may help reduce colorectal cancer.

Dietary fiber may also promote gut health. The human gut contains many different kinds of microbes that help with digestion, absorption, and detoxification. Junk food is just one of the main sources of the negative change in this flora.

In the gut, healthy microbes get replaced by unhealthy ones, thus increasing overall gut health deterioration. Everything eaten affects the gastrointestinal flora, so it is better to eat foods that will promote the growth of healthy micro-organisms. Also, the gut plays a vital role in a healthy immune system. The micro-organisms in the gut make up roughly 75 percent of the immune system.

Junk food, Immune System Response, and Coronavirus/COVID-19

During this coronavirus/COVID-19 pandemic, when everything is critical, a person’s most essential asset is their immune system. Avoiding or severely limiting anything that weakens the immune system response is one of the best things to do in times of crisis.

So, while junk food is delicious, convenient, and affordable, it will not cover up the long-term harm it does to your body. The deficiencies of antioxidants, minerals, and fiber, along with the inflammasome activation and innate immunity reprogramming, make a person’s body more vulnerable to all kinds of infections and chronic inflammatory conditions that indirectly weaken the immune system.

Thus, it is better to adopt a healthy lifestyle and dietary pattern, as this will not only benefit your immune system but your overall health. One should consume fruits, green vegetables, whole grains, legumes, healthy fats, and quality protein to strengthen the body and its immune system response.


Final Thoughts

Now, I am sure that you have read all of this and are saying to yourself, ‘okay, I get it. Junk food weakens my immune system response, so I need to avoid my favorite foods forever?!’ 

While health experts would like to say ‘yes, you are correct,’ they also understand that we are only human. Thus, to forgo junk food completely is impossible for most people. 

For this reason, many believe in the 80/20 approach. This approach is practical because it allows for some wiggle room for our favorite snacks and foods. The 80/20 concept requires the consumption of healthy foods 80-percent of the time while allowing for some unhealthy consumption 20-percent of the time. In this way, we do not feel deprived.

Our goal should be to strive to eat healthily most of the time. It helps fuel our bodies and strengthens our immune system responses.


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