Does chicken soup really fix a cold? A dietitian weighs up six common winter ailment myths

Cold and flu season is certainly upon us, and with it, a growing demand for vitamins, minerals and supplements designed to support immune function and ward off nasty bugs and infections.

Whether you reach for a nourishing bowl of bone broth or a mega-dose of vitamin C when you have a cold, this is the time of year when many people turn to folk remedies.

So, before you rush out and grab more vitamins or start boiling up a pot of bones, here’s a breakdown of some of the most common remedies for when we are feeling less than our best.

Chicken soup supports the immune system

True. There are plenty of remedies when it comes to food and nutrition, but it may come as a pleasant surprise to hear that there is scientific evidence to show that a bowl of soup with a bone broth base does have a number of key nutritional benefits linked to immune function. The bones that form the base of a soup broth contain an amino acid called carnosine, a molecule shown to help the body fight infection in its early stages by helping to inhibit the migration of infected cells around the body. This means that while a packet soup mix is unlikely to be doing your immune system any favours, a rich chicken or beef-based soup may indeed do the trick.

Vitamin C helps fight a cold

False (for the most part). While it may be tempting to down orange juice when you have a sniffle, there is mixed evidence about the role vitamin C supplementation plays in reducing illness. At low doses, there is no strong evidence to show that vitamin C supplementation will stop you from getting sick. But there is some to show that super-loading this water-soluble vitamin may reduce the duration of cold-like symptoms if you catch it within the first day. The take-home message? If you feel a cold coming on, a glass or two of juice or eating a few oranges or kiwifruit won’t do you harm and may slightly shorten the time you have to deal with the sniffles.

Feed a cold, starve a fever

False (partially). While some of us immediately go off all food when we are unwell, there are plenty more who power through. So, should you eat, or not, if you are unwell? Indeed, a closer look at the science reveals there is some data on this question. The evidence suggests that the second part of this adage – that we should fast to treat a fever – does seem to be a myth. While our baseline nutritional status affects immune function overall, when you have a fever or a cold, the body needs nutrients to fight infection, and fluids to avoid dehydration. While you may lose your appetite when sick, you are better off ingesting light foods and fluids, such as soup, tea, water and electrolyte drinks. There are no nutritional or immune-related benefits to be gained by not eating at all; rather, recovery is about eating the right foods and keeping hydrated when you are unwell.

Drinking milk increases phlegm

False. When you are feeling far from your best, an icy cold milkshake or creamy latte may be the last thing on your mind, but should you avoid dairy if you have a cold to avoid increased mucous production? While there is no strong evidence to show that dairy increases the production of mucous, dairy milk and even soy milk do change the way the mouth feels after consumption, which may be the reason milk is so often associated with mucous. The body isn’t producing more mucous but when you are already congested it feels as if there is more. So while there is no specific reason to avoid dairy when you are sick, you may feel better if you avoid it.

Garlic fights infection

False. Garlic has been used as a medicinal treatment for infection for thousands of years, and while it is known that the organosulfides found naturally in both onions and garlic help to support immune function by regulating cytokine production, there is less data to specifically show that garlic consumed in the diet or via supplements can directly affect our propensity to become unwell. Of the small number of studies available, one published in the journal Advances in Therapy more than 20 years ago found a reduced risk of developing a cold when using supplementary garlic, in a trial of 146 adults, although this was a one-off study. While there are few risks associated with using garlic supplements, from an overall health perspective, routinely adding garlic to your diet is likely to have general long-term health benefits rather than any specific gains relating to colds and flu.

Honey relieves a sore throat

True. At some point in your life, chances are someone has suggested a mug of hot water with lemon and honey to treat a sore throat. The good news is they were on the right track with this age-old remedy. Honey is known for its natural antimicrobial properties, and studies suggest that treating upper respiratory tract infections with honey as a dietary addition may help to reduce the symptoms of infection. So it’s worth considering this option the next time you feel a tickle in your throat or a cough coming on.