Starve a fever or starve a cold? Whatever the old wives’ tale says, it’s wrong. When the flu hits, nutrition counts most and that means eating even if you don’t feel like it.
“The immune system is what helps prevent or fight off infection and it’s also the most sensitive one in the body to even small changes in nutrition,” said Catherine Field, a professor in the department of agricultural, food and nutritional science at the University of Alberta. “It’s important to not skip meals when you’re feeling ill.”
Mistakenly, people sometimes believe that falling sick presents a good opportunity to diet, since appetites tend to flag anyway, but that’s not a good idea, Field warns. “We are all trying to lose weight, but this is not the right time. When a person gets the flu, the virus is fighting the immune system and good nutrition helps the cells stay active to protect that immunity.”
To make sure that nutritional requirements are met, Field advises following Canada’s Food Guide, which recommends eating from every food group: vegetables and fruits; grain products; milk and alternatives, and meat and alternatives.
To measure healthy food intake, Field recommends a trip to the Dietitians of Canada web-site, where, using a system called EATracker, people can gauge their personal consumption over 24 hours: www.dietitians.ca/public/content/eat_well_live_well/english/eatracker.
“It will tell you what your diet is missing,” Field said.
If the thought of solid food isn’t appealing while you are ill, Field advises using meal replacements, boosted with a daily multivitamin. “There are lots of substitutes like meal replacement breakfast cereals, liquid nutrition supplements, even diet supplements, which contain the vitamins and minerals you need.”
Key nutrients to include in a healthy diet that boosts the immune system include omega-3 fatty acids — found in oily fish such as sardines, salmon, tuna and mackerel — and DHA and EPA fatty acids, found in fortified yogurt, eggs, orange juice, milk and bread.
Fruit is also a big immune booster, filled with antioxidant nutrients vitamin C, vitamin E and betacarotene, as well as phytochemicals, found in plants. Foods such as peas, lentils and beans are also good choices, Field said.
“One other nutrient that people don’t think about is water. We have to keep hydrated, especially when we are ill. It’s important for the function of all cells.” She recommends drinking six to eight 250-millilitre glasses per day.
Along with eating, some light exercise during illness is also important, Field added.
“A way to help prevent and battle viral infections like the flu is regular exercise, which has been shown to increase the number and activity of natural killer cells in the blood that battle viruses. Even when you are sick, a little exercise is not a bad thing. You can still self-isolate yourself from others, by walking around your yard or up and down stairs. There’s nothing wrong with your muscles.”