Things That Can Weaken Your Immune System

A strong immune system is vital to stay healthy so do you know what can make yours weaker?


If you want to boost your immune system then these are all the factors you need to bear in mind if you want to make some very healthy changes.


Not getting enough sleep can make you more likely to catch viruses or germs. And you also may take longer to get better.

That’s because your body can’t make as many infection-fighting cells and proteins called antibodies that help defend against illness. Your body releases certain proteins that help the immune system, called cytokines, only during sleep.


Stress and worry aren’t great germ fighters. Just having anxious thoughts can weaken your immune response in as little as 30 minutes.

Constant stress takes an even bigger toll and makes it harder to fend off the flu, herpes, shingles, and other viruses. Talk to your doctor if you can’t shake your worry or if it gets in the way of normal life.

Vitamin D

You may know you need it for strong bones and healthy blood cells. But vitamin D also helps boost your immune system. You can get it in eggs, fatty fish, and fortified foods like milk and cereal.

Sunlight is another key source. In the summer, just 5-15 minutes of rays on your hands, face, and arms 2-3 times a week usually is enough. In the winter, you might need a bit more.


Of course some medications are necessary, but if you have any concerns please discuss them with your doctor. The ones you need to be cautious about drugs to treat allergies, arthritis, lupus, IBS, and organ transplant.

Corticosteroids are one example, as are TNF inhibitors for inflammation and chemotherapy for cancer.

Fruit and vegetables

These foods may help your body make more of the white blood cells you need to fight off infections. Fresh produce and nuts and seeds pack a lot of zinc, beta-carotene, vitamins A, C, and E, and other nutrients you need for a healthy body.

Plant-based foods also fill you up with fibre, which helps lower your body fat percentage, which can strengthen your immune response.


Nicotine from cigarettes, chewing tobacco, or any other source can weaken your body’s ability to fight germs. Yes, vaping counts, too. And it’s not just the nicotine. Other chemicals in e-liquids seem to suppress your immune response, especially when you inhale them through vaping

Smoke from marijuana can also inflame your lungs. If you use it regularly, you may have the same breathing problems you can get from nicotine cigarettes.

That means coughing up coloured mucus called phlegm and a higher chance of lung infections.

High fat diet

Oils can hinder germ-fighting white blood cells. And high fat diets over time can upset the balance of bacteria in your gut that can help immune response. Look for low-fat dairy with no added sugar, along with lean protein like seafood, turkey, and chicken, or lean cuts of beef with any visible fat cut off. Also, being obese seems to make you more likely to get the flu and other infections, like pneumonia.

Too little time outside

If you tend to travel everywhere by car or public sunlight with little walking you are missing out on some great benefits.

Sunlight may energise special cells in your immune system called T-cells that help fight infection. But being outside brings other benefits, too.

Vitamin D from sunlight, and if you can walk in the woods or parks then many plants phytoncides and other substances you breathe in that seem to bolster your immune function.


Of course the occasional drink will do you no harm, but just overdoing it once slows your body’s ability to fight germs for up to 24 hours.

Over time, drinking too much blunts your body’s ability repair itself. That may be part of the reason you’re more likely to get illnesses like liver disease, pneumonia, tuberculosis, and certain cancers.

If you are drinking, try to keep it to one drink a day for women.


There is some evidence that sorrow, especially if lasts a long time, can depress your body’s immunity. The effect can linger for 6 months, but may go on longer if your grief is deep or doesn’t ease.

Talk to your doctor, a counsellor or a mental health professional if you need help with a loss or traumatic event.


Regular aerobic exercise appears to help your body fight illness caused by viruses and bacteria. That’s in part because it helps blood get around your body more efficiently, which means germ-fighting substances get where they need to go.

Scientists continue to study exactly how exercise helps boost your immune system, but the many health and mental benefits are fairly well established.

Dance, walk, swim, garden – whatever you enjoy make it regular and just enough to raise your heart rate.


Weekly intimacy seems to help boost your immune system compared to those who have it less often.

Sex raises levels of a germ-fighting substance called Immunoglobulin A, or IgA. But more may not always better.

Couples who had sex more than twice a week had lower levels of IgA than those who had no sex at all.

Helpful information:

These are simple ‘fixes’ that can help boost your own natural immune response. Herbs are also well established such as Echinacea, Elderberry and Astragalus which can help reduce the duration and severity of illness.

Human beings are the only animals that don’t produce their own vitamin C and this vitamin has been much studied for its role in boosting immunity so ensure you get sufficient levels.

If your hormones are also out of balance that will affect your ability to fight infection and viruses and progesterone in particular has an anti-inflammatory effect which will also be helpful.