At What Age Does Your Immune System Weaken?


As you get older, you focus on taking care of your skin to look and feel better about yourself. Unfortunately, most people are too focused on their skin to focus on something arguably more important, their immune system. As we get older, it becomes increasingly important that we do whatever we can to take care of our immune system’s health. We can do this by enacting a healthy lifestyle. 

Is There A Specific Age When Your Immune System Weakens?

Unfortunately, aging is inevitable and something we will all go through as we get older. We often get asked ‘at what age does your immune system weaken?’ by our customers. While we all go through the aging process, there is no specific age where we can definitively say that aging begins. 

However, we can say that, as far as skin goes, we begin aging as early as our 20s. Beyond that, everyone begins aging at different times and how quickly the aging process goes will also differ for different people. There are several factors that play a role in aging and we will go over those factors later in the article. 

What Weakens The Immune System?

Your immune system is arguably the most important part of your body, as it protects you from viruses, bacteria, and infections. Therefore, taking care of your immune system should be your number one priority. The best way you can protect your immune system is by avoiding things that can weaken the immune system. Here are some things that can weaken the immune system: 

  • Anxiety and stress - It is not at all uncommon to see a weakened immune system due to stress. Constant stress takes a big toll on your body
  • Low Vitamin D - Vitamin D helps boost your immune system and a lack of Vitamin D can lead to a weakened immune system
  • Medications - Certain medications can contain TNF inhibitors for inflammation 
  • Lack of fruits and veggies - Fruits and veggies contain crucial nutrients for your immune system
  • Smoking - Cigarettes, chewing tobacco, or any other source of nicotine can weaken your body’s ability to fight germs

Cutting these out of your life will require some serious lifestyle changes. While it may seem overwhelming, these changes will help you feel better, look better, and live longer. 

Can Babies Have Weakened Immune Systems?

Newborn babies are more susceptible to bacterial infections as it takes time for their immune system to develop. However, there is some research that suggests that their bodies let microbes into their body intentionally. Their bodies engineer the vulnerability deliberately, allowing beneficial microbes to colonize the baby’s gut, skin, mouth, and longs. 

Babies actually reach the immune system development age while in the womb. In fact, from the moment a baby travels down the birth canal, bacteria and fungi begin their colonization. Macrophages can be found in the fetal intestine by 11 or 12 weeks of gestation, and quantities increase rapidly during the fourth and fifth months of pregnancy.

How Does The Immune System Change With Age?

Our immune system, just like every other part of our body, changes as we age. Unfortunately, a lot of these changes are for the worst. As you grow older, your immune system does not work as well. Here is how age and the immune system are tied together:

  • Slow to respond - The older we get the slower our immune system responds, leaving us more prone to illness
  • Autoimmune disorders - As we get older, the chances of our body’s turning on us get higher and higher
  • Your body needs more time to heal - Our immune system protects our body and works hard to help our body recover from an illness or injury. However, as we get older this process becomes slower
  • Detection ability goes down - As you get older your immune system’s ability to detect and correct cells declines which can increase your risk of cancer

Many of these deteriorations are inevitable, however, you can slow their speed by implementing some of the healthy lifestyle choices.

Do T Cells Decrease With Age?

T cells play a huge role in our immune systems ability to fight off foreign invaders and help our body recover from illness. These cells are known as ‘killer cells’ because they are able to directly kill virus-infected cells as well as cancer cells. T cells are also able to utilize small signaling proteins, known as cytokines, to recruit other cells when mounting an immune response.

Unfortunately, our T cells have a definite life span, after which these die off and are cleared from the system (1). In our younger age, we replace these T cells frequently and usually without a problem. As we get older, it becomes more and more difficult for our bodies to replace those T cells consistently. 

What Age Has The Best Immune System?

There’s no real way of knowing the age of the strongest immune system. As we discussed earlier, there are several different factors that play into the health of our immune system. If you don’t take proper care of yourself, your immune system can deteriorate rather quickly compared to someone who takes good care of themselves. 

What we can say is that most children reach full immune system development around the ages of 7 or 8. You should frequently check with your child’s doctor to ensure that your child’s immune system has developed properly. Their doctor can run tests to ensure their immune system is functioning properly. 

Supplements That Boost Your Immune System

It’s important to note that there is no definitive research that points to supplements boosting the immune system directly. However, it is believed that supplements play a role in boosting your immunity. For example, supplements such as spermidine supplements can induce bodily functions that can improve immune system effectiveness. 

Spermidine achieves this by inducing autophagy throughout the body. Autophagy is the body’s process of replacing old, potentially damaged cell parts with newer, healthier ones. Unfortunately, most Americans fail to get their recommended daily intake of spermidine through their diet. Supplements can help ensure that you get the vitamins, nutrients, and minerals that you need on a daily basis. 

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  • Don Moxley - Director of Applied Science

    Don Moxley is the Director of Applied Science at Longevity Labs. Moxley draws upon his career as an athlete, a sports scientist, and an instructor to lead and educate on the science of autophagy and longevity.