It's the cold season and many people catch cold as the temperature drops. Sneezing, coughing, runny nose, sore throat, headaches - there's nothing worse than the common cold. And despite the wisdom of the ages and the sages, there's no cure.

We all know you're supposed to stay warm. Traditional Chinese medicine also recommends drinking ginger soup - ginger contains hot yang energy - to warm you up inside and fight the invading culprit of "pathogenic cold."

"Healthy energy can effectively defend us against ailments like colds," says Dr Fang Hong, chief physician of the Respiratory Medicine Department of Longhua Hospital. "But when healthy energy is weakened by fatigue or other serious ailments, pathogenic elements from outside can easily invade the human body through pores, the nose or mouth, and cause disease."

Many people's immune systems have failed to cope with falling temperatures, he says.

Western medicine says colds are caused by viruses - we can see them under a microscope. Antihistamines, cough suppressants, aspirin, throat lozenges and other medicine are prescribed for symptoms. Drink lots of liquids, stay warm and wait it out.

TCM divides colds into four categories according to their four basic causes - pathogenic cold, wind, damp and heat. Cold and wind are common in winter and spring; damp and heat in summer, but several elements can occur together. They require different treatments.

In cold/wind-caused colds, patients usually have nasal congestion, runny nose, itchy throat, aching limbs, coughing with thin phlegm, but no sweating. They usually have a pale tongue with thin coating.

Dispelling pathogenic cold is the main treatment. TCM patent medicine like zheng chai hu yin chong ji (medicinal granules with Chinese thorowax root as the main ingredient) is often prescribed to relieve symptoms.

People with this kind of cold should eat a relatively plain diet with less meat. Foods that promote sweating to dispel pathogenic cold are recommended, including chili, onions, green onions, ginger and brown sugar.

Drinking a bowl of hot ginger soup, then going to bed under thick quilts will promote sweating - it's one of the most effective methods to relieve cold symptoms, especially fever.

Colds caused by pathogenic heat and wind tend to occur in summer and autumn. Symptoms include congestion and runny nose, sore throat and swollen glands, coughing with thick phlegm, headache, aching limbs, but little sweating. The tongue is often yellow with a thin coating.

These cold sufferers need to clear pathogenic heat from their systems. TCM patent drugs like yin qiao jie du wan (pill with honeysuckle and forsythia as the main ingredients) are often prescribed.

A plain, low-protein diet is advised. Stay away from hot and spicy foods and alcohol. Drink more sour juice, like hawthorn or kiwi fruit, to improve the appetite.

Colds caused by pathogenic summer heat and damp cause fever, vomiting, headache, chest congestion and poor appetite. TCM patent drugs like huo xiang zheng qi wan (pills with ageratum as the main ingredient) are prescribed to dispel pathogenic damp and regulate qi (energy).

Flu, though sharing some symptoms with colds caused by heat and wind, is more serious, with high fever, aching muscles and serious headache. There can be respiratory problems. The tongue is red with a yellow coating. Patients need drugs that can help detoxify and fight the virus. See a doctor.

Medicinal food for colds

Colds caused by pathogenic cold and wind

Ginger and brown sugar soup

Ingredients: Ginger (10g), brown sugar (15g)

Preparation: Chop ginger into thin slices and cook soup. Add brown sugar. Drink while hot.

Function: Relieves cold symptoms like chills and runny nose with watery mucus.

Green tea, ginger and green onion tea

Ingredients: green tea (9g), two slices of ginger and three green onions

Preparation: Cook all ingredients and drink while hot.

Function: Relieves cold symptoms like chills and runny nose with watery mucus.

Garlic (cooked and uncooked)

Eat several cooked and uncooked slices of garlic every day - if you don't care about your breath. If you do, take garlic pills.

Function: Boosts the immune system, helps prevent colds due to pathogenic cold and wind.

Colds caused by pathogenic heat and wind

Honeysuckle and black bean sauce congee

Ingredients: Honeysuckle (9g), black bean sauce (9g), rice (60g)

Preparation: Make congee, sweeten with sugar.

Function: Relieves fever, headache and sore throat.

Colds caused by summer heat and damp

Huo xiang (ageratum) drink

Ingredients: Huo xiang (15g), chen pi (dried orange peel) (6g), sugar

Preparation: Cook with water, sweeten with sugar, drink while hot.

Function: Relieves headache, chest congestion, vomiting and diarrhea.

For people susceptible to colds

Green onion, ginger and sticky rice congee

Ingredients: Five green onions, three slices of ginger, and sticky rice (100g)

Preparation: Make congee, eat while hot, eat often.

Function: Helps prevent colds.

(Shanghai Daily December 2, 2008)