Cancer and cancer treatments weaken the body’s immune system by affecting white blood cells that protect against disease. As a result, your body can't fight infection as well as a healthy person’s body can. Good food hygiene, such as the basic guidelines that follow, is important for everybody. However, if you've had a bone marrow transplant or your white cell count is low, particularly during chemotherapy, extra care needs to be taken with food preparation as you'll be more susceptible to foodborne illness.
Most food poisoning results from improper handling and improper storage of food. Speak to your doctor or dietitian regarding any special food handling conditions which may apply to your stage of treatment.
It's important to take care and potentially avoid the following high-risk foods, as they may contain bacteria or viruses that can cause foodborne illnesses:
Feeling sick (nausea), with or without vomiting, is a possible side effect of cancer or its treatment. Vomiting sometimes follows nausea and may be brought on by treatment, stress, food odours, gas in the stomach or bowel, or motion sickness. The following information may help:
If you have persistent vomiting, don’t try to force food down. Sip small amounts of liquid as often as possible. Try dry ginger ale, cold flat lemonade, soda water, Lucozade or chilled tomato juice. You might also find it helpful to suck a hard lolly, flavoured crushed ice cubes or an iceblock. If you can’t keep fluids down, and vomiting lasts for more than 24 hours, see your doctor because you may become dehydrated.
If your vomiting has stopped, but you still feel nauseated and full, it's important to eat small, frequent meals. Hunger, or an empty stomach, can aggravate or prolong nausea. Start by drinking cold or iced drinks. Make up drinks that are half milk (or skim milk) and half water (or soda water). These mixtures are surprisingly settling and soothing. If you like sweet drinks, try a spoonful of ice cream in a glass of lemonade. You can also try diluted fruit drinks, Bonox, clear broth and weak tea. Jellies can be satisfying too.
When you feel you can drink without discomfort, eat small amounts of solid foods, such as plain dry biscuits, toast or bread with honey, jam, Vegemite or Marmite. Try jelly and cooked cereals (such as lemon sago or boiled rice), and then try soft stewed fruits, such as apples, pears or peaches. Start drinking milk gradually and in small amounts, or try yoghurt, which is more easily digested. Have food in small amounts and have something to eat or drink at regular intervals.
As soon as you can, increase your food intake until your eating returns to a good level. Your doctor or dietitian may advise you to take additional nourishment (perhaps supplements) on your good days to make up for the days when you can’t eat properly. You may find the following foods difficult to tolerate when nauseous, so you may need to limit them (however it’s sometimes trial and error):
Cancer and some treatments can cause heartburn, which is a burning sensation in your oesophagus and throat due to reflux. The discomfort may cause you to reduce your food intake and lead to weight loss.
If you have heartburn, avoid or minimise foods that make it worse. Try not to eat large amounts of chocolate, highly seasoned spicy foods, high-fat foods (such as fried food, pastries, cream, butter and oils), tomato and tomato products, citrus fruits, coffee (including decaf), strong tea, soft drinks and alcohol.
Constipation is when your bowel motions are difficult to pass and infrequent. It may be caused by some medications, particularly strong pain medication, a diet low in fibre, lack of exercise, or by not having enough fluids to drink (dehydrated).
When increasing the amount of fibre in your diet it's essential that you also increase fluids, to prevent the fibre making your constipation worse. Medication to help maintain comfortable bowel function is generally given to people taking codeine and morphine preparations. In these cases, eating extra dietary fibre may not help, and may make you feel overfull and uncomfortable.
It's important that you discuss constipation with your doctor who can prescribe medication if needed to help you maintain regular bowel function (e.g. suitable fibre supplements or laxatives).
Things to consider when you have constipation:
Try to get into a regular routine with your meals, which can help to regulate the digestive processes.
Diarrhoea means your bowel motions are watery, urgent, and frequent. You may also get abdominal cramping. Diarrhoea may be caused by a number of different factors including treatment, medications, infections, food sensitivity or anxiety.
Diarrhoea induced by radiotherapy (usually to the pelvic area) doesn't necessarily require a change in diet. Dietary changes to help ease radiation induced diarrhoea haven't been well established; but it's important to maintain an adequate diet and replace lost fluids to prevent dehydration.
Things to consider when you have diarrhoea:
You may find it helpful to contact the National Continence Helpline on 1800 330 066. This is a free service which provides information and referrals to local services for people who are experiencing problems with continence.
During chemotherapy or radiotherapy to your abdomen or pelvis, your intestines can become irritated leading to other problems such as abdominal discomfort or more flatus (wind) than usual. You may also need additional time to recover from surgery to the bowel area.
Eat and drink slowly, take small mouthfuls and chew your food well to avoid swallowing air.
Irritation of the large bowel (colitis) and rectum (proctitis) – may be experienced after radiotherapy to the pelvis. Some people feel the need to empty their bowels more often, perhaps without much result. Straining can cause discomfort, and there may be some blood or mucus in motions. These changes are usually temporary and will correct themselves.
In the short term, symptoms may be relieved by reducing your fibre intake and avoiding fatty or fried foods, rich gravies and sauces, sausages and spicy foods. Eat soft or cooked fruit, fine wholemeal bread (without coarse pieces of grain or seeds) and bran to provide soft bulk. Drink plenty of fluids.
Irritation of the small bowel (enteritis) – may occur because of chemotherapy or radiotherapy to the abdomen or pelvis. You may experience some abdominal discomfort (like cramps or wind pain), episodes of fluid and pale bowel motions and more flatulence (wind) than usual. These changes usually correct themselves within a week or so after treatment. Speak to your doctor if you experience symptoms for more than a week.