Many cancer patients think it is normal to lose a lot of weight during treatment.
But it is not. Shed more than 5 per cent of your body weight and you could reduce your body's ability to battle the disease.
To correct this misconception, the Singapore Cancer Society and healthcare company Abbott have compiled a booklet containing healthy eating tips for cancer patients.
These include ways to combat weight loss, and problems such as loss of appetite and nausea that cancer patients face.
The booklet will be given to newly diagnosed cancer patients and will also be made available to those undergoing treatment.
Eating right is important because the body sheds weight differently during cancer and finds it harder to put it back on, said Associate Professor Koo Wen Hsin from the National Cancer Centre Singapore.
"You lose not fat but lean muscle," he said. "Then, you tend to feel very weak and fatigued, like during a bout of bad flu."
And as cancer patients tend to have a limited appetite for food, every mouthful matters.
"You should go for foods with high nutrition value but are low in volume, like fish, meat and eggs," Prof Koo said.
While vegetables are healthy and should not be left out, patients must consume a lot more of them to get the same nutritional impact.
In September, the Singapore Cancer Society will start cooking classes and nutrition training workshops for cancer patients and their caregivers. These will be held at its new rehabilitation centre in Jurong's Jem mall.
The centre's senior manager, Ms Susan Leen, said: "People get conflicting views from friends and relatives. Some people go to the extremes and go totally vegetarian, or take a lot of meat."
Mr Ricky Chiu was diagnosed with head and neck cancer in 1997. During the month of intensive chemotherapy and radiotherapy, he lost more than 10kg and consulted library books on what best to eat.
"I had nobody to advise me," said the 61-year-old former bus driver. "I had ulcers in my mouth, and whatever food I ate, I had difficulty swallowing because of the pain. And I couldn't taste anything."
Mr Chiu made a full recovery in a year, after eating plenty of fish and vegetables, and cutting down on oil and salt. It was not always tasty, he said, but it was necessary. "If I didn't eat, I would have had no energy to fight the cancer."
Here are some tips from the society to deal with eating-related issues commonly faced by cancer patients:
1. Appetite loss
Eat several small meals a day, instead of three large meals. Try to have a bedtime snack, as it will provide extra calories but won't affect your appetite for breakfast. When it is hard to eat, drink oral nutritional supplements, as they are easy to consume.
Drink beverages between meals, rather than during meals. Avoid oily foods, as fat stays in the stomach longer and makes you feel full. You should also cut down on foods that cause gas, such as beans, cabbage, and cauliflower.
3. Changes in your sense of taste or smell
Serve foods cold, or at room temperature, as this will make them taste and smell less strong, and be more palatable. Have lemon drops, sour plum, or preserved orange peel to remove any undesirable taste that lingers in your mouth. If your metal utensils leave a bitter taste, switch to plastic or porcelain instead.
Eat fibre-rich foods, such as vegetables, fruits, and wholegrain products. Drink at least eight to 10 cups of fluid a day - but avoid caffeinated drinks as they tend to dehydrate the body. Use laxatives only with your doctor's advice.
Drink plenty of mild, clear liquids throughout the day to prevent dehydration. Avoid foods which are oily or rich in fibre, and switch to lactose-free dairy products.
6. Dry mouth
Sip fluids throughout the day, or suck on ice cubes. However, avoid mouthwash containing alcohol as this tends to dry your mouth out further. Eat steamed, stewed, or soupy foods that are easier to swallow. Your doctor may also prescribe an oral lubricant to relieve the discomfort.
Instead of three large meals a day, switch to several smaller meals. Do not skip meals, as having an empty stomach tends to make nausea worse. If you have nausea in the morning, eat dry toast or crackers before getting out of bed. Small amounts of salty or sour foods - such as preserved plums - may help.
8. Sore mouth or throat
Cook foods until they are tender, and cut them into small pieces. Do not cook them with spices such as chili powder, cloves, and pepper. Avoid rough-textured foods such as dry toast and crackers.
9. Weight loss
Have small, frequent meals throughout the day. Eat when it's time to eat - not when you're hungry. Try and increase the caloric and nutritional intake of each mouthful of food. For example, eat crackers with kaya, add condensed milk into oatmeal, and drink soy milk instead of plain water.
This article was first published on May 15, 2015.
Get a copy of The Straits Times or go to straitstimes.com for more stories.