Home remedies for coughs and colds: which ones work according to science and which are myths

As temperatures change, the first colds arrive, and with them the old familiar recipes: honey and lemon, grandma's chicken soup, eucalyptus steam. Social media has added a few more, some sensible and some downright dangerous. What does the evidence say? Here's a practical guide to easing symptoms safely at home.

First, a reminder: the common cold is caused by viruses, mainly rhinoviruses. Antibiotics don't work against it and should only be used when a doctor prescribes them. Most colds clear up on their own in 7 to 10 days; home remedies help you get through them more comfortably.

1. Honey: the best-supported option

It's the home remedy with the strongest evidence for coughs. A review published in BMJ Evidence-Based Medicine in 2020 concluded that honey eased the frequency and severity of coughs from upper respiratory infections better than usual care. The Cochrane review on children reached similar conclusions.

How to use it: one or two teaspoons on their own or stirred into a warm herbal tea, especially before bed.

Important: never give honey to babies under 1 year old because of the risk of infant botulism.

2. Salt-water gargles

They soothe a sore throat and help clear mucus. A small Japanese study suggested that gargling with water might reduce how often people catch respiratory infections. Dissolve half a teaspoon of salt in a glass of warm water and gargle several times a day, without swallowing.

3. Warm drinks and broth

The famous chicken soup has some basis: a lab study at the University of Nebraska found it might have a mild anti-inflammatory effect. Beyond that, warm fluids keep you hydrated, loosen mucus and are comforting. Herbal teas, broths and warm water with lemon are all good choices.

4. Steam and humidity

Breathing moist air can ease congestion and a dry, scratchy throat. A hot shower or a clean humidifier in the bedroom are the safest options. Scientific reviews haven't found a clear benefit of steam inhalation on how long a cold lasts, and steam inhalation over boiling water causes burns every year, especially in children. If you try it, use hot but not boiling water, and never with young children.

5. Saline nasal rinses

Rinsing with saline helps clear a blocked nose and is safe for children and adults. If you make the solution at home, always use boiled and cooled water or distilled water, never water straight from the tap.

6. Rest and sleep

It sounds obvious, but good sleep helps your immune system. Raising your head slightly with an extra pillow may reduce nighttime coughing caused by postnasal drip.

Remedies with limited evidence

• Ginger: ginger tea can be soothing and help with nausea, but there's no solid evidence it shortens a cold.
• Vitamin C: taking it regularly may slightly reduce how long colds last, but starting once you're already sick doesn't seem to help most people.
• Zinc: some studies show zinc lozenges taken early may shorten symptoms, but they can cause a bad taste and nausea. Zinc nasal sprays have been linked to loss of smell and should be avoided.
• Echinacea: study results are mixed.

What NOT to do

• Don't use alcohol or "hot toddies" as treatment: they dehydrate you and disrupt sleep.
• Don't rub camphor or menthol products on the chests of children under 2.
• Don't put onions in your socks or around the room thinking they "absorb viruses": it's a myth.
• Don't combine cold medicines without reading the labels: many contain acetaminophen (paracetamol), and it's easy to exceed the safe dose.
• Don't give over-the-counter cough and cold medicines to young children without talking to a pediatrician.

When to see a doctor

Get medical advice if you have a high fever (above 39 °C / 102 °F) or one lasting more than three days, trouble breathing or wheezing, chest pain, a cough that lasts more than three weeks, severe ear pain, or if symptoms improve and then suddenly get worse. In babies under 3 months, any fever needs medical assessment. Older adults, pregnant women and people with chronic illnesses should seek advice sooner.

Prevention is easier

Washing your hands often, airing out rooms, coughing into your elbow and staying home when you're sick are still the most effective measures. And don't forget the vaccines recommended for your age, such as the flu shot, usually available in the fall.