They ween’t lying when they said you can survive on love and fresh air.

Being in open spaces, research has proved, strengthens your immunity since white blood cells that fight bacteria need oxygen to function effectively. A free supply of oxygen means your blood pressure and heart rate is in check since the body isn’t overworking itself to acquire it. Blood oxygen levels are also linked to serotonin, the ‘happiness hormone’, which is why you are more likely to slip into a refreshed, relaxed state when in green outdoors.

The hitch, of course, is that most urban residents end up spending close to nine hours a day in air–conditioned offices, often following it up with a whole night’s sleep in closed, cool bedrooms.

Your lungs are the first hit, which is why respiratory infections including common cold, frequent headaches, itchy throat and symptoms of flu, are most common among young, urban professionals. Fresh air that helps the lung’s airways to dilate, releasing airborne toxins from your system, is scant in swanky AC offices.

Dr Gauri Mankekar, consultant ENT surgeon at Hinduja Hospital, says an air conditioner is able to cause cooling through the process of evaporation. "Thanks to the very manner in which it functions, an AC ends up drying the mucous membranes in the nose and mouth," she says. Our nasal passages, sinuses and throat depend on moisture in the membranes for their immune functions. When moist, the immunity cells are able to attract and trap viruses, bacteria and allergens, acting as the body’s first line of defence against airborne pathogens. Most air–conditioners aren’t fitted with humidifiers, upping levels of dryness in the surrounding air.

This constant and direct exposure to cold, dry air can ruin the skin, robbing it off its elasticity, leaving it itchy, scaly and aged. Skin conditions like dermatitis and eczema are common among those who spend long hours in cool, dry recycled air, says dermatologist Dr Sushil Tahiliani. More harmful than the low temperatures is the growth of mould, a microscopic fungi, that lives inside AC vents and ducts, with high moisture levels and dust offering it a
good breeding ground. While filters fitted in AC units are designed to prevent the spread of bacteria and virus, if not cleaned regularly, with the accumulation of pollutants over time, they end up hosting bacteria. "Since it’s the same stale air that’s re-circulated all day, we end up inhaling viruses and droplet infections," says Dr Mankekar. Ideally, filters should be cleaned once a month. When the AC serviceman arrives, make sure he uses anti-fungi chemical solutions instead of using a simple vacuum and brush that will only loosen the mold.

• While working in a ventilated office isn’t an option for most of us, try and reduce the number of time you sleep in a closed, AC room. Open all windows, doors and let in sunlight every morning. Air out your linen in between washing cycles.
• Make sure the office AC is set to 25 degrees. This ‘average’ temperature helps because it doesn’t ‘shock’ a new entrant who might be walking in from the blistering heat outside. Sudden and extreme temperature fluctuations in the body can also affect the joints.
• Dr Mankekar suggests you layer your body with sufficient clothing inside AC rooms, and un–peel when outdoors.
• Install a warm mist humidifier at work, if possible. Else, keep a large vessel with a wide mouth filled with water in a corner of the office. It can work towards circulating moisture in the air. Keep yourself hydrated by drinking water every few hours, splashing your eyes with water and going out for a quick stroll during lunch hour to get a dose of sunlight and oxygen.