People with low immunity

Learn how to stay food safe when you have lower immunity. With on-going illness, medication, a recent hospital stay, pregnancy, being very young or frail, your risk of getting sick from food is higher than normal.

When you are less able to fight the harmful pathogens that can cause a foodborne illness, you are more likely to get sick and your illness may be more serious.

No food is 100 percent safe at all times for all people. There are some simple food safety rules to help you and your family avoid getting sick from foodborne illness if you or anyone in your family has low immunity.

Food that may be contaminated with bacteria, fungi, parasites, viruses and toxins can cause stomach upset, nausea, vomiting and diarrhoea or worse. ‘Foodborne illness’ is the term used when you are sick because of contaminated food.

What you need to do to reduce your risk of getting a foodborne illness may depend on what is causing your low immunity. Your doctor or dietician may have special advice for you based on the state of your immunity or your individual circumstances. Ask your doctor if you have low immunity.

Reasons why your immunity might be low

Anyone suffering a chronic illness, recovering from surgery, the frail elderly, very young babies and pregnant women may suffer low immunity. More detail is in the chart below.


Why this might cause your immunity to be lower than normal




If you have advanced cancer or are taking chemotherapy drugs or having radiotherapy.


HIV/Aids directly affects your immune system’s cells. If your disease is more advanced you have a higher risk of infection.

Inflammatory bowel disease

If you have ulcerative colitis or Crohn’s disease. Especially if you are taking higher doses of drugs such as steroids (cortisone, prednisone), or immune suppressants such as salazopyrine.

Neutropenia (low white blood cell count)

A low blood neutrophil cell count (particularly less than 0.5 x 109 cells/L), can result in a higher risk of infection. Neutropenia may occur with radiation therapy or chemotherapy.

Surgical or medical treatments


Transplant procedures

Especially if your transplant (kidney, liver, heart, lung, bone marrow) was recent. Or if you are taking anti-rejection drugs such as tacrolimus or cyclosporine.

Immunosuppressive drugs

Prednisone and azathioprine are used for medical conditions, including arthritis and autoimmune disease. Ask your doctor whether you are on this type of drug and if the dose is enough to leave you at risk of a foodborne illness.

Low stomach acidity

Stomach acid provides a defence by killing many bacteria. When acid is absent or reduced, bacteria may grow and cause an infection.

Your immunity may be lower if you have had a stomach operation that has reduced the amount of acid your stomach produces. Alternatively, if you are on medication for gastric reflux, or are regularly taking antacids.

Being older or very young and sick



If you are an older person and have ongoing (chronic) illnesses, you may have low immunity.

Premature babies and sick children

Especially babies who are very premature and children who have other serious illnesses.




While you are pregnant your levels of immunity are lower than usual.