AC at 22°C best for your health, say experts

As heatwave alerts continue across northern states of India, including Delhi, going up to 45 degrees Celsius, a new government move about setting AC temperatures could help more than just power savings, it could also be a step toward protecting public health.

Union Housing and Urban Affairs Minister Manohar Lal Khattar recently announced that a standardised temperature range for air conditioners will soon be implemented across sectors.

Under the new rule, users will not be able to cool indoor spaces below 20 degrees Celsius or heat them above 28 degrees Celsius.

The regulation, expected to apply to both buildings and vehicles, is aimed at curbing excessive energy consumption and reducing environmental impact.

"This is a first-of-its-kind experiment,” Khattar said, “to bring uniformity in air conditioning use and promote energy efficiency.”

While the move is framed as a response to climate concerns and growing energy demands, doctors say the decision could have meaningful benefits for the body, especially during intense summer months when people rely heavily on cooling systems to stay comfortable.

WHY AC BETWEEN 22 AND 28 DEGREES CELSIUS IS IDEAL FOR HEALTH

Dr. Suranjit Chatterjee, senior consultant in Internal Medicine at Indraprastha Apollo Hospital, explains that air conditioners set at excessively low temperatures can disrupt the body's natural ability to regulate heat.

“When you're sitting in a very cold environment and then suddenly step outside into 44 or 45 degrees, your body experiences a temperature shock,” he tells IndiaToday.in. "This transition can trigger colds, fatigue, or even stress the internal organs."

He likens the body to a natural thermostat that is constantly working to maintain internal balance.

However, artificially cold environments can override these mechanisms.

“If your body isn't given time to acclimatise, it reacts. And this reaction is more severe in elderly people or those with heart, liver, or kidney diseases,” Dr. Chatterjee says.

While the government's new limits cap the minimum temperature at 20 degrees Celsius, Dr. Chatterjee recommends keeping it even higher, ideally between 22 degrees Celsius and 24 degrees Celsius for most people.

“This range provides adequate comfort without creating a drastic temperature gap between the indoors and the outside,” he says, adding, the closer the indoor temperature is to the outdoor heat, the better your body can adjust.

This is especially important during 'loo' conditions (hot, dry winds common in North India) when the difference between



indoor and outdoor temperatures becomes more extreme.

He also points out that temperature preferences aren't uniform. The ideal setting depends on various factors: the direction your room faces, the quality of curtains or insulation, existing health conditions, and even the time of day.

"A room facing the sun might need slightly more cooling, whereas someone with certain medical issues might find lower temperatures harmful,” he adds.

Dr Vibhu Kawatra, pulmonologist and allergy specialist in New Delhi, says cold temperatures at night can also affect sleep.

"Staying in a cold room overnight can disturb your sleep. It's actually better to sleep in a room that’s slightly warm than too cold. A warmer environment helps relax your muscles, which promotes better sleep. On the other hand, if it’s too cold, your muscles may subtly contract to keep your body warm, which can disrupt sleep. This mild shivering is your body’s way of regulating temperature. Also, in colder conditions, your body works harder to generate heat, which can lead to increased hormonal activity," Dr Kawatra tells IndiaToday.in.

Dr Prashant Sinha, Head of emergency, PSRI Hospital, New Delhi, tells IndiaToday.in, "I often see patients who unknowingly invite health issues simply by setting their AC too low. While a temperature of 16 or 18 degrees may feel pleasant after coming in from the heat, it can actually do more harm than good."

Setting the AC below 20 degrees Celsius can create a stark difference between indoor and outdoor temperatures.

This abrupt contrast shocks the body and may lead to issues like headaches, sore throat, muscle stiffness, dry skin, and even respiratory infections. People with conditions such as asthma, sinusitis, or arthritis often find their symptoms worsening in overly chilled environments.

Maintaining the air conditioner between 22 degrees Celsius and 24 degrees Celsius allows the body to stay cool without being exposed to artificial cold stress.

"This range is close enough to natural comfort levels and ensures smoother adaptation between indoor and outdoor environments," adds Dr. Sinha.

The government’s mandate also ties into long-standing efforts by the Bureau of Energy Efficiency (BEE), which in 2020 prescribed 24C as the default setting for room air conditioners.

Lowering cooling demands helps not just individual power bills but also reduces the strain on electricity grids during peak summer.

"Extreme cooling is neither necessary nor beneficial. What’s ideal is a moderate, consistent temperature that supports both comfort and energy conservation,” Dr. Chatterjee emphasised.