While a take-away burger and oily chips obviously won't do you any good when you're sick (or healthy for that matter), there are a number of things you shouldn't be eating or drinking while you're trapped under the control of the dreaded flu.
When you're sick, says clinical nutritionist Sally-Ann Creed, you need to avoid thick and sticky mucous production and inflammation. 'If you put inflammation in the picture, you have the perfect environment for a virus, bacterial or fungal infection to thrive.'
Here, find a list of foods you need to avoid when you're feeling under the weather this winter.
Eating any mucous-forming foods will make you feel worse when you're sick, advises Creed. Within minutes of eating or drinking a dairy product, she says, you'll find yourself having to clear your throat. 'Dairy traps bacteria in the mucous, giving it a fantastic medium to multiply quickly.'
Nutritional therapist, Lynne Brown, agrees. 'Dairy, whether pasteurised or raw, is the leader in forming sticky mucous. Make sure to avoid milk, skim milk, butter, cheese, cottage cheese, cream, yoghurt and ice cream.'
Bread, pasta and rusks, for example, should be avoided when sick, says Creed. Refined foods are like dairy in that they encourage mucous production as well as cause allergies.
Avoid any gluten-based foods, agrees Brown. This includes wheat, barley and rye. Gluten in wheat has large protein molecules, which are difficult to digest, she says.
Stop eating sugar and any foods containing sugar, as it will further impair your immune system, warns Brown. 'There are plenty of studies that show even a teaspoon of sugar will reduce the immune system's killer cell activity in your body for a few hours after you've eaten it.'
She suggests you avoid fizzy drinks, concentrated cooldrinks, chocolate, pastries and cakes. 'The minerals needed to digest sugar – chromium, manganese, cobalt, copper, zinc and magnesium – have been stripped from the sugar during the refining process,' says Brown. This forces the body to deplete its own mineral reserves to process the sugar, further compromising your health, she explains.
Fruit juice, as well as too much fruit, is also a big no-no, says Creed. Because fruit can cause an unnecessary sugar spike, it is considered to be far too sweet to eat when you're fighting a virus or infection, she adds.
'All acid-forming foods should be avoided when ill,' advises Brown. 'These include wheat, dairy, red meat, poultry, eggs, rice, grains, margarine, sugar, soya, caffeine, black tea and alcohol.' With a negative effect on your body's pH level, she says, these foods produce not only too much acid, but a lot of mucous. 'Acid-forming foods suppress antibody production, making it hard for the immune system to function.' Too much acid decreases your body's ability to absorb minerals and nutrients, she adds, making your body more susceptible to sickness and hampering your recovery.
Meat and animal products use too much energy and trap pathogens inside your body instead of expelling them out of your system, says nutritional therapist Andrea Jenkins.
FATTY AND FRIED
Fried, convenience or processed food high in fat reduces circulation and increases inflammation, says Jenkins.
'Avoid all processed foods containing common allergens like MSG, sulphites, preservatives, artificial colourants and flavourants,' says Brown. Metabolising these non-foods will place a huge burden on an already weakened immune system, she says. For example, she adds, sulphites will significantly affect your breathing when you're sick.
SO, WHAT CAN YOU EAT?
'You need soups and vegetable juices,' advises Creed.
A liquid and hydrated diet not only flushes out toxins and unwanted compounds in the blood, it keeps food easy to digest, light and nutritious, agrees Jenkins. Opt for cinnamon, ginger or lemon teas and choose leak, cabbage, parsley, celery, broccoli or garlic soups, she says.
And, adds Brown, a low-fat diet will speed up the healing process.