Immune System’s Weight Unveiled

The adult human immune system comprises over one trillion cells and typically weighs approximately one kilogram, varying with an individual’s size

Glenn Burgess

Your immune system might weigh about 1 to 1.2 kilograms and have around 1.8 trillion cells. Ron Milo at the Weizmann Institute of Science in Israel explains that the immune system is a complicated network of different cells, each with important jobs.

For instance, lymphocytes are a type of white blood cell that create antibodies to fight off viruses and bad germs. Mast cells, another part of the immune system, help your body deal with swelling and injuries.

To learn more about what makes up a person’s immune system, Ron Milo and his fellow researchers decided to count all the immune cells in the body. They used data from previous studies to estimate the number of immune cells in various parts of the body.

They also did lab tests on tissue samples from people of similar ages—men and women, including 10-year-old kids—who didn’t have any known health problems.

Here’s what they discovered: A 73-kilogram man between 20 and 30 years old has roughly 1.8 trillion immune cells, which together weigh about 1.2 kilograms.

A woman of the same age who weighs 60 kilograms has about 1.5 trillion immune cells, which add up to 1 kilogram. For a 10-year-old child, their immune system has around 1 trillion cells and weighs about 0.6 kilograms.

In both males and females, and whether they are kids or grown-ups, about 40 percent of all immune cells are lymphocytes and neutrophils, which are another type of white blood cell.

Together, they make up about 15 percent of the entire weight of the immune system. These cells are mainly found in the bone marrow, lymph nodes, and the spleen.

Even though we often call them white blood cells, most of these cells actually stay in the bone marrow and the lymphatic system. Only a very small part of them circulates in the bloodstream at any given time, explains Milo.

Macrophages, the immune cells that gobble up harmful germs, are the heaviest of them all and make up nearly half of the immune system’s total weight. Surprisingly, they only make up about 10 percent of all the immune cells.

Ron Milo believes that by charting our immune system, we can improve our understanding of how our bodies protect against infections and different health issues.

He says, “This can help us make infection models with numbers, aiding the development of better treatments for medical problems.”

Tips to stay healthy

Individuals with a weakened immune system can follow several measures to enhance their chances of staying well and preventing infections.

Good hygiene

For people with weakened immune systems, one of the simplest ways to stay healthy is by practicing good hygiene, especially frequent handwashing. The Centers for Disease Control and Prevention (CDC) recommend washing your hands:

Before, during, and after preparing meals and snacks.
Before eating.
After blowing your nose, sneezing, or coughing.
Before and after tending to a cut or open wound.
After coming into contact with someone who is sick.
After using the restroom or assisting a child.
After changing a diaper.
After handling animals, their food, or waste.
After touching garbage.

Proper handwashing significantly reduces the risk of illness. According to the CDC, it can reduce cases of infectious diarrhea by 58% in people with weakened immune systems.

The CDC also emphasises that handwashing with soap and water can protect children and decrease deaths from pneumonia and diarrheal diseases in children under 5 years old.

Avoid people who are sick

Individuals with weakened immune systems should steer clear of close contact with anyone who has a cold or another infection.

Viruses and other contagious illnesses can be transmitted through close contact between people, as well as through the respiratory droplets produced when someone coughs or sneezes.

While it may not always be feasible to avoid contact with sick individuals, those with a compromised immune system should refrain from hugging, kissing, or sharing food and drinks with the unwell person until the illness has cleared.

Follow a doctor’s advice on vaccines

While doctors generally recommend that most individuals stay up to date with their vaccinations, they might advise those with weakened or compromised immune systems to delay or avoid certain vaccines.

If a short-term illness or medication is the cause of the weakened immune system, it may be possible to receive the vaccine once the illness has resolved or the treatment has stopped.

Examples of vaccines that doctors may recommend delaying or avoiding include:

MMR vaccine (measles, mumps, and rubella)
Live flu vaccine
MMRV vaccine (combining MMR with varicella-zoster, which protects against chickenpox)
Rabies vaccine

The CDC recommends a vaccination schedule that most people should follow. However, individuals with weakened immune systems should consult with their doctor to determine which vaccines are safe for them, and then follow the doctor’s advice. Vaccines play a crucial role in preventing severe illness.

Manage stress

Stress can further weaken the immune system, making a person more vulnerable to illness. Research suggests that excessive stress increases the likelihood of falling sick.

Individuals with weakened immune systems should prioritise stress management. Effective stress-reduction practices include:

Yoga
Meditation
Massage
Engaging in hobbies and activities
Maintaining connections with friends, family, & supportive individuals

These activities can help reduce and manage stress, ultimately supporting a healthier immune system.

Get enough sleep

Research indicates that sleep deprivation has a similar impact on the body’s immune system as stress.

Insufficient sleep can disrupt the regular production of white blood cells, which are essential for a healthy immune system.

The CDC recommends that adults aim for at least 7 hours of sleep per day, while infants and children should get between 8 and 17 hours of sleep, depending on their age. A good night’s sleep is crucial for maintaining a strong immune system.

Eat a healthful diet

Maintaining a healthy diet is essential for individuals with a weakened immune system. A balanced and nutritious diet can contribute to their overall well-being.

Doctors typically advise people with compromised immune systems to consume a diet rich in vegetables and fruits, as these foods provide essential nutrients.

For those who are highly immunocompromised, such as individuals undergoing cancer treatment, extra precautions to prevent foodborne illnesses may be necessary. These precautions can include:

Washing all fruits and vegetables before peeling or consuming them.
Avoiding undercooked meats, fish, and eggs.
Promptly refrigerating food.
Choosing pasteurised juices and dairy products over unpasteurised alternatives.

Exercise regularly

Regular exercise is crucial for maintaining overall health. It not only strengthens the body but also triggers the release of endorphins, which can help reduce stress levels. However, individuals with weakened immune systems need to exercise with caution, as overdoing it can further weaken the immune system.

Therefore, it’s advisable for people with a weak immune system to avoid:

Exercising at excessively high intensity.
Overdoing exercise too frequently.
Engaging in prolonged workouts without taking breaks to rest.

Instead, they should focus on regular, low-intensity exercise, which is likely to be beneficial for their well-being.

Consider taking supplements

Certain vitamins and minerals play a role in influencing the immune system. For instance, a deficiency in vitamin C can lead to weakened immunity. Other vitamins and minerals that can impact immune function include:

Vitamin A
Vitamin D
Vitamin E
Iron
Folic acid
Zinc

It’s important to understand that while these nutrients are essential for supporting the immune system, they cannot cure or prevent diseases on their own.

Ideally, these nutrients should be obtained from a well-balanced diet. However, in cases where it’s challenging to get all the necessary nutrients from food, supplements may be beneficial for immune support.

Many different supplements, such as multivitamins, are readily available in health stores and online.

Final Words

The immune system is a sophisticated network of blood cells and organs that shields the body from harmful germs, preventing illnesses. Frequent infections may indicate a weakened immune system.

Individuals with a weak immune system can take measures at home to maintain their health and optimise their immune function.