Fixing your sleep routine

How do I fix my sleep schedule?

To fix your sleep schedule, start with the time you get up, not the time you go to bed. Pick one wake time and keep it every day, weekends included. Your bedtime will follow.

A fixed wake time sets your body clock for the rest of the day¹. Your body clock, or circadian rhythm, is the inner 24-hour timer that tells you when to feel alert and when to feel sleepy.

Timing matters as much as hours. A UK study followed 60,977 people. People with more regular sleep times had a 20–48% lower risk of death than the least regular sleepers².

Get outside soon after you wake. Daylight can reach about 10,000 lux, while bright office lights rarely go above about 500 lux⁴. Lux is a measure of how bright light is.

A few minutes on the balcony, or the walk to the bus stop, tells your body clock that the day has started.

Then give the evening the same shape every night. The same few steps, in the same order, teach your body that sleep is coming¹. The table is set for an 11 pm bedtime. If you sleep earlier or later, move every row by the same amount.

Why can't I fall asleep at night?

If you can't fall asleep at night, something from the evening is usually keeping your body in "day" mode. The common ones are caffeine, a late heavy dinner, a warm room and a bright screen. Change one at a time.

Caffeine lasts longer than most people think. Its half-life is usually 4–6 hours⁵. Half-life is the time your body takes to clear half of it. So half the caffeine from a 4 pm chai is still in you at 8 to 10 pm.

A cup of tea has 40–120 mg of caffeine. A cup of brewed coffee has 70–140 mg⁵. Three cups of office chai through the afternoon add up.

In a review of many studies, caffeine cut total sleep by 45 minutes and added 9 minutes to the time it took to fall asleep⁶. You may not feel it. Your sleep still does⁶.

Stop caffeine about 9 hours before bed: a standard cup of coffee needs at least 8.8 hours⁶. For an 11 pm bedtime, that means the last cup by about 2 pm. Cola and energy drinks count too.

Is it okay to sleep right after a late dinner?

Sleeping right after a late dinner can bring on acidity once you lie down. Eating late at night affects sleep for many people, so aim to finish dinner 3 hours before bed⁷.

In many Indian homes, dinner at 9:30 or 10 pm is normal. The whole joint family waits to eat together, and bed follows soon after.

In one study, people who went to bed less than 3 hours after dinner had 7.45 times the odds of reflux, compared with people who waited 4 hours or more⁷. Reflux is acid coming up the food pipe. It can wake you in the night.

If you can't move dinner earlier, make it smaller. Keep the bigger meal for lunch, and go easy on fried food, heavy gravies and sweets at night.

Don't lie down straight after eating. A slow walk around the building or the colony, or sitting up to talk with the family, gives the stomach time to settle.

How can I sleep in the summer heat without AC?

To sleep in the summer heat without AC, keep the sun out by day, move air across your body at night, and cool your skin before bed. A ceiling fan on high and a warm shower about 90 minutes before bed are the two biggest steps¹⁴.

Your body has to lose heat to fall asleep. Your core temperature, the heat deep inside the body, starts to fall about 2 hours before bedtime⁸. A hot room slows that fall.

Hot nights cost real sleep. When nights go above 30 °C, people sleep just over 14 minutes less on average, mostly because they fall asleep later⁹.

People in hotter places lose more sleep for each extra degree, not less⁹. You don't simply get used to the heat.

Across a year, it adds up. Climate Central, a US group of scientists, worked out how much sleep night-time heat took from people in cities around the world from 2020 to 2025¹¹. Indian cities are near the top.

Homes hold the heat. In 50 low and middle-income homes in Chennai, night-time indoor temperatures rarely fell below 31 °C. They stayed near 34 °C into the early morning, with humidity above 75%¹⁰. Many of the poorer homes had only ceiling fans¹⁰.

Concrete roofs keep the day's heat in. Studies in Ahmedabad and Hyderabad found rooms 2–5 °C hotter than the air outside at night¹⁰.

Start in the afternoon. Close the curtains and windows on the sunny side. Open them after sunset, once the air outside is cooler than the room.

Without AC, moving air matters most. It dries sweat, and drying sweat is how the body cools itself in the heat¹⁸. Run the ceiling fan on high, or point a pedestal fan so the air moves across your body.

A warm shower sounds wrong in summer, but it works. Water at 40–42.5 °C, taken 1–2 hours before bed, helped people fall asleep about 10 minutes faster¹⁴. Warm skin sheds heat quickly afterwards, and the body cools down⁸.

On the hottest nights, wet your face, neck and arms with a damp cloth before you lie down under the fan. Wet skin and a fan together help the body lose heat¹⁸.

Sleep in loose cotton, under a thin cotton sheet at most.

Know the limit of a fan. When the air is above 35 °C, a fan alone does little to cool you, and it can make older people hotter¹⁸. On those nights, wet your skin, drink water, and sleep in the coolest room in the house.

What is the best room temperature for sleep?

The best room temperature for sleep is about 18 to 20 °C (65 to 68 °F)⁸. Few Indian bedrooms get that cool in summer, so aim for cooler than now, with air moving.

Both heat and cold make people wake more often in the night¹⁹. So the right setting is the one where you feel comfortable under a light cotton sheet, neither warm nor cold.

If you have AC, start at 24 °C. New star-rated ACs in India are set to 24 °C by default, a setting chosen to save power²⁰. Run the ceiling fan on low with it. Go lower only if you still feel hot.

Waking up chilled at 4 am breaks sleep as surely as waking up hot¹⁹. Keep a light sheet within reach, and don't set the AC so low that you need a heavy blanket.

Is a fan or an AC better for sleep in humid cities?

In humid cities like Mumbai and Chennai, an AC with the fan on is best for sleep, because the AC dries the air and the fan moves it. Without AC, a fan still helps on most nights¹⁸.

Humidity is the amount of water in the air. Sweat cools you only when it dries, and in humid air it dries slowly¹⁸.

Humidity makes heat harder on sleep. In humid heat, people wake more and get less deep sleep and REM sleep¹⁹. Deep sleep is the stage that restores the body, and REM sleep is the dreaming stage (Chapter 1).

A fan is worth running all night in humid weather. It keeps air moving across your skin so sweat can dry. Below about 35 °C, that helps you cool¹⁸.

With AC, keep the fan on low as well, so the cool, dry air reaches your skin.

Does using my phone before bed affect sleep?

Yes, using your phone before bed affects sleep. Screen light tells your brain it is still daytime, and what you watch keeps your mind busy. Put the phone away 30–60 minutes before bed¹.

Light at night slows or stops melatonin⁴. Melatonin is the hormone your body makes in the dark to signal that it is night.

Blue light from screens has the strongest effect on melatonin and your body clock. The ideal is to cut back on screens 2–3 hours before bed⁴.

Night mode helps, but it doesn't remove the effect⁴.

Keep the room itself dark. Your eyelids don't block enough light, so a streetlight through the window or the glow of a standby light still reaches you⁴. Thick curtains or an eye mask fix most of it.

Is sleeping in on weekends bad? Can I catch up on sleep?

Sleeping in on weekends is fine if it is short. A long lie-in moves your body clock, so the night before work is hard and Monday morning feels like jet lag. Keep your weekend wake time close to your weekday one.

Can you catch up on sleep? Partly. A good night helps, but one long lie-in can't undo a week of short nights. Earlier bedtimes work better.

Sleep researchers call the weekend swing "social jet lag": living on one clock on work days and another on days off. It affects about two-thirds of people in Western countries and is linked to a higher body weight³.

If you are tired on Saturday, get up at your usual time and take a short nap after lunch instead. Chapter 3 explains how long a nap should be.

After a late wedding or a festival night, do the same.

How do I sleep after a night shift?

To sleep after a night shift, treat your day sleep as your night. Make the room as dark and quiet as night, sleep at the same time after each shift, and ask the household to protect those hours.

Night work is hard on sleep. Among 190 nurses in South India on night and rotating shifts, almost half (46.3%) slept poorly¹⁶.

Morning light on the ride home tells your body clock the day has started, just when you need to sleep⁴. Dark glasses on the way home help.

Make the bedroom dark with thick curtains, or use an eye mask. Daylight around the edges of a curtain is enough to wake you early⁴.

Daytime homes are noisy: the pressure cooker, the doorbell, the vegetable seller, children back from school. Tell the family your sleep hours, keep your phone on silent, and use earplugs if you need them.

Have your main meal during the shift. On the way home, keep it light, not a heavy breakfast just before bed.

Have your tea or coffee early in the shift, not in the last few hours. Caffeine still in your blood at 8 am makes day sleep shorter⁵.

How can two people sleep well in one bed?

Two people sleep well in one bed when they agree on one lights-out time, keep the room cool and dark, and deal with snoring early. Separate thin sheets help when one sleeps hot or turns a lot.

Sharing a bed can help sleep. In a German lab study of 12 couples, partners had about 10% more REM sleep when they slept together than when they slept apart²². Their sleep stages also moved more in step²².

A partner can also disturb you. In the same study, people moved their arms and legs more when they shared the bed²².

Snoring is a common problem. In a small Mayo Clinic study of 10 married couples, the wives slept more than an extra hour a night once the husbands' snoring was treated²³.

Loud snoring with pauses or gasps can be a sign of sleep apnoea. Chapter 1 explains the signs.

Some couples choose to sleep apart. In a 2023 survey of 2,005 adults in the US, more than a third said they sometimes or always sleep in another room because of their bed partner²⁴.

In many Indian homes, a second room is not possible. The bedroom may also hold a child, a grandparent or a cousin who is visiting. Then the same steps work for everyone in the room.

If one of you goes to bed later, agree on a lights-out time for the bedroom. The late one can get ready in another room, with the lights low. Light at night cuts melatonin⁴, and an eye mask helps the one who sleeps first⁴.

On hot nights, use 2 thin cotton sheets instead of 1. Each of you can cover up or throw the sheet off without waking the other. Keep the fan on all night, so air moves across both of you¹⁸.

If one partner turns a lot or gets up at night, separate sheets also mean less pulling. Leave a gap between you where the bed allows. Chapter 4 covers children who share a bed.

Why do I wake at 2 am and can't sleep again?

Waking up at 2 am and not falling asleep again is often caused by heat, a drink earlier in the evening, or worry. Keep the room cool and dark, and leave the phone and the clock alone.

Heat is the common cause in Indian summers. Many rooms stay hot until dawn¹⁰. If your fan or AC is on a short timer, the room may warm up again around 2 am. Let the fan run all night.

Alcohol makes some people drop off faster, but it breaks up the second half of the night. As it wears off, light sleep and waking go up¹⁵.

Don't check your phone or the clock. The light wakes you more⁴, and counting the hours left until the alarm adds worry.

If you are still awake after about 20 minutes, get up, sit in low light and go back when sleepy¹. Chapter 5 explains why this works.

If it keeps happening, Chapter 5 also explains how to tell if it is insomnia, and what helps.