How does pancreatic cancer affect diet and digestion?
When you eat, your body breaks down your food – this is part of digestion. Pancreatic cancer can affect how well your body can digest food. Problems with digestion can cause symptoms, including losing weight or having pale, oily poo that floats (steatorrhoea) and other changes to your bowel habits.
The pancreas plays an important role in digesting food, as it produces enzymes that help to break down food. Nutrients from the food can then be absorbed into the blood and used by the body. Different pancreatic enzymes help to break down foods containing fat, protein and carbohydrate.
The pancreas also produces hormones, including insulin and glucagon, which control sugar levels in the blood. Pancreatic cancer can reduce the number of hormones the pancreas makes, which can cause diabetes.
How does pancreatic cancer affect digestion?
Pancreatic cancer can reduce the number of enzymes that your pancreas makes. It can also block the enzymes from getting to the bowel, where they are needed for digestion. For example, the cancer can block the pancreatic duct, which carries the enzymes from the pancreas to the small intestine.
This means that food is not properly digested, and the nutrients in the food aren’t absorbed. This is called malabsorption. It can be managed with pancreatic enzyme replacement therapy.
Having surgery to remove all or part of the pancreas may also affect the number of enzymes that the pancreas makes.
It is common for people with pancreatic cancer to get symptoms caused by problems digesting food. Symptoms include:
- losing your appetite
- losing weight, or struggling to put weight back on
- indigestion or heartburn
- runny poo (diarrhoea) – read our tips on coping with diarrhoea
- problems emptying your bowels (constipation)
- pale, oily, floating poo (steatorrhoea)
- tummy pain or discomfort
- bloating or wind
- feeling full up quickly
- needing to empty your bowels urgently, especially after eating.
Some people also develop diabetes. Some symptoms can be caused by other things, such as jaundice.
Some treatments or medicines can hide these symptoms. For example, if you are taking strong painkillers called opioids (such as morphine), these may cause constipation and hide the symptoms of diarrhoea. Your medical team will help you manage any symptoms you have alongside the medicines you are taking. It is important that you don’t stop taking any medicines without speaking to your doctor, nurse or dietitian first.
Jaundice is a symptom of pancreatic cancer. It can develop if the cancer has grown to block the bile duct, which carries bile from the liver to the small intestine. Bile is a fluid that is made in the liver and helps with digestion.
Jaundice makes your eyes and skin turn yellow, and you may feel itchy. It can also cause loss of appetite, taste changes, feeling and being sick, dark urine and pale poo. These symptoms normally get better once the jaundice is treated.
Steatorrhoea is caused by fat in poo. You may notice that your poo is often pale, oily, smell worse than normal, and is difficult to flush down the toilet. It happens if your body isn’t making enough enzymes to digest the fat in your food properly. It also happens if the enzymes are blocked from getting to the bowel, where they are needed for digestion. Steatorrhea can be managed with pancreatic enzyme replacement therapy.
Losing weight is a common symptom of pancreatic cancer, and can be caused by problems with your digestion. Diabetes can also cause weight loss.
Weight loss can affect how you deal with the symptoms of the cancer. It can also affect how you deal with treatments such as chemotherapy or surgery. Weight loss can be upsetting and affect how you feel generally.
Your doctor, dietitian or nurse will work out what is causing the weight loss, and how this can be managed. You may need to take pancreatic enzymes to help you digest your food and maintain your weight.
Your medical team will also help you make changes to your diet so you can get more calories and protein. When someone loses weight quickly, they often lose muscle and strength too. Having more protein in your diet and doing gentle physical activity can help rebuild muscle. This can help you to feel better and have more energy.
Your medical team may also recommend nutritional supplements, which are drinks or powders that have extra calories and protein in them.
There are a lot of diets claim to help cancer, but a lot of these aren’t based on good evidence. If you have pancreatic cancer it’s important not to cut anything out of your diet, or take any supplements, without speaking to your doctor, nurse or dietitian first.
"In view of my weight loss it was suggested by a Specialist Nurse at Pancreatic Cancer UK that I may benefit from enzyme tablets. I started taking the capsules and noticed straightaway less discomfort on eating. My energy levels started to increase and I have very slowly started to gain some weight."
Find more about diet and pancreatic cancer
Updated January 2020
Review date January 2023
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