How Much Water Should You Drink in India's Different Climates?

By 3 pm, the bottle you filled this morning is often still mostly full, next to a cup of tea or coffee that has gone cold.

Most of us know we should drink more water. What is harder to find is a number we can actually picture, and one that fits where we live. Litres are hard to track, and a glass is a different size in every kitchen.

This post answers one question: how much water do you need a day in India? For a healthy adult, India's own nutrient guidelines put the water needed from drinks at roughly 1.5 to 3.8 litres a day, depending on body weight and how active you are. That works out to about 1.5 to 4 refills of one 1 litre reusable bottle. Where you live and the season change the picture too, from desert heat and humid coasts to winters in the hills, so you will also find how to adjust for your climate.

What the research says about the exact figures

Healthy adults in India need roughly 1.5 to 3.8 litres of water a day from drinks, depending on body weight and activity. The Indian Council of Medical Research and National Institute of Nutrition (ICMR-NIN) sets this out in its 2020 nutrient requirements for Indians, at 32 to 58 ml per kg of body weight for men and 27 to 52 ml per kg for women.

• In ICMR-NIN's ranges, sedentary people sit at the low end and people doing heavy work sit at the high end.
• The figures cover water from drinks, and the water in your food comes on top.
• ICMR-NIN's reference adults weigh 65 kg (men) and 55 kg (women). Applying the ranges to those weights gives this:

In a 1 litre bottle, that is about 1.5 to 3 fills for the woman and about 2 to 4 fills for the man. In a 500 ml bottle, double those numbers.

Global references land in the same place. The US National Academies' figures of 2.7 litres for women and 3.7 litres for men count total water, including food, and roughly 80 percent of that comes from drinks.

How to Calculate Your Daily Water Intake by Body Weight

To calculate your daily water intake by body weight, multiply your weight in kilograms by the ICMR-NIN range for your sex: 32 to 58 ml per kg for men and 27 to 52 ml per kg for women.

• Use the lower end of the range for desk-based days and the higher end for physical work.
• For example, a 60 kg woman works out to 60 x 27 = 1,620 ml at the low end and 60 x 52 = 3,120 ml at the high end, or about 1.6 to 3.1 litres.
• Any drink counts toward the total: chai, nimbu paani, buttermilk and plain water, so your bottle does not have to carry the whole amount.
• After that, adjust for heat, humidity, cold or altitude, because climate changes how much water you need.

What Are IMD Heat Wave and Cold Wave Ranges, and Why Do They Matter for Your Water Intake?

The India Meteorological Department (IMD) declares a heat wave or a cold wave when temperatures cross set limits for the type of terrain. Those declarations matter for hydration because they trigger the health advisories that tell people to change how they drink: more water, more often, in heat, and warm fluids in the cold.

What counts as an IMD heat wave?

IMD declares a heat wave when the actual maximum temperature reaches at least 40°C on the plains, 37°C at coastal stations or 30°C in hilly regions, and one more condition is met:

• The maximum runs 4.5°C to 6.4°C above normal (a heat wave) or more than 6.4°C above normal (a severe heat wave).
• On the plains, the maximum reaches 45°C or more (a heat wave) or 47°C or more (a severe heat wave).
• At coastal stations, the maximum runs 4.5°C or more above normal.

IMD also flags warm nights, which it considers only when the maximum is 40°C or higher. A warm night is a minimum temperature 4.5°C to 6.4°C above normal, and a very warm night is more than 6.4°C above normal.

Heat waves mostly hit the interior plains between March and July, building over northwest India and spreading east and south. IMD notes that Tamil Nadu, Kerala, coastal and south interior Karnataka, Lakshadweep and the Bay islands are not affected by heat waves because of maritime air. That does not mean the weather there is comfortable: humid heat can be hard on the body without an official heat wave.

What counts as an IMD cold wave?

IMD declares a cold wave when a station's minimum temperature is 10°C or less on the plains or 0°C or less in hilly regions, and one of these conditions is met:

• The minimum runs 4.5°C to 6.4°C below normal (a cold wave) or more than 6.4°C below normal (a severe cold wave).
• On the plains, the minimum is 4°C or less (a cold wave) or 2°C or less (a severe cold wave).
• At coastal stations, the minimum runs 4.5°C or more below normal and is 15°C or less.

The cold wave season runs from November to March, and it is most frequent in December and January. Seventeen states and union territories form the core cold wave zone: Punjab, Himachal Pradesh, Uttarakhand, Jammu and Kashmir, Ladakh, Delhi, Haryana, Rajasthan, Uttar Pradesh, Gujarat, Madhya Pradesh, Chhattisgarh, Bihar, Jharkhand, West Bengal, Odisha and Telangana.

Why do IMD heat and cold wave warnings matter for how much water you drink?

• They trigger the health advisories. IMD sends its warnings, issued by meteorological sub-division and by district, to health departments, disaster management authorities, railways and the media. The advice you then see, such as drinking water even when you are not thirsty in heat, or drinking warm fluids in a cold wave, follows from those warnings.
• They get more serious in steps. In IMD's impact-based heat warnings, heat wave conditions lasting two days mean a moderate health concern for infants, older people and people with chronic diseases, and the suggested action is to avoid heat exposure. For severe or longer heat waves, the likelihood of heat illness rises for people in the sun or doing heavy work, and the suggested action adds keeping cool and avoiding dehydration. At the top level, the likelihood of heat illness and heat stroke is very high in people of all ages.
• Thirst is a weaker guide at both extremes. In serious heat, India's health advisory says thirst is not a good indicator of dehydration. In the cold, thirst can drop by up to 40 percent.
• The limits differ by terrain. Because the thresholds are 40°C, 37°C and 30°C, the same maximum temperature can mean something very different in the hills, on the coast and on the plains.

How can you check IMD warnings where you live?

• IMD publishes district-wise weather warnings, updated every four hours, at mausam.imd.gov.in. During the March to June hot-weather season, IMD also issues special heat wave bulletins twice a day.
• IMD's alerts use four colours: green (no advisory), yellow (be aware), orange (be prepared) and red (take action).
• When your district has a heat warning, drink water regularly even if you are not thirsty, carry water, and stay out of the sun between 12 noon and 3 pm. When it has a cold wave warning, drink warm fluids regularly, check your urine colour, and avoid alcohol.

How Climate Changes Your Daily Water Needs in India: Heat, Humidity, Cold and Altitude

ICMR-NIN's ranges are built around body weight and activity, so climate adds another layer. How much water you need in India also depends on your region and the month.

• Hot plains and dry heat. IMD's heat wave threshold on the plains is 40°C. Drink before you feel thirsty, carry water when you travel, and stay out of the sun between 12 noon and 3 pm.
• Humid coasts, the east and the northeast. IMD's heat wave threshold for coastal stations is 37°C, lower than on the plains, because humidity makes the heat feel worse and increases sweating. Warm nights add to it, because the body cannot cool down overnight. When the air is damp, sweat evaporates less easily, so enough fluid and salt matters. ORS (oral rehydration solution), buttermilk and lemon water all help.
• Hill and mountain regions in summer. IMD's heat wave threshold for hilly regions is just 30°C, so the hills are not exempt. Keep drinking regularly through summer.
• Cold winters. Seventeen states and union territories fall in the core cold wave zone, and the cold wave season runs from November to March. Cold does not make water less important. It makes thirst a weaker guide: in a controlled study, cold exposure reduced thirst by up to 40 percent, even when people were short of water. Fluid deficits of 3 to 8 percent of body mass have been reported in people working in the cold. Cold wave advisories recommend drinking warm fluids regularly, and urine colour is a better check than thirst.
• High altitude. Above roughly 2,500 metres, and sometimes lower, staying hydrated matters because dehydration can look like altitude sickness. Forcing extra water does not prevent altitude illness and raises the risk of dangerously low blood sodium, so drink steadily instead of overdoing it.
• Mild weather. When the weather is neither hot nor cold, ICMR-NIN's ranges are the best fit. Drinking with meals and when you are thirsty is enough for most healthy people.

You might be thinking: if thirst is a fair guide, why drink when you are not thirsty? On an ordinary day, thirst plus drinks with meals is enough for most healthy people. Very hot weather and cold weather are the exceptions, heat because you lose more and cold because thirst goes quiet. In both, drinking at regular intervals works better than waiting to feel thirsty.

How to Tell If You Are Drinking Enough Water

The colour of your urine is a simple way to check whether you are drinking enough water, and it is especially useful in cold weather, when thirst is a weaker guide.

• Pale yellow with little or no smell usually means you are well hydrated.
• Darker urine with a stronger smell is a sign you need more fluids.
• If you are not thirsty and your urine is pale yellow, you are likely getting enough water.
• Some medicines change urine colour, so treat it as a guide, not a verdict.

A quick check around mid-afternoon works well, when the morning's bottle is still on the desk.

Can Mild Dehydration Affect Focus, Mood and Work Performance? What the Research Shows

Mild dehydration can affect attention, working memory, mood and tiredness, but the research is mixed.

• A lab trial of healthy young men found that mild dehydration led to more errors on an attention test, slower working memory and more tension, anxiety and fatigue.
• The evidence is not one-sided. A smaller study found no effect on thinking speed, with possible effects on mood and exercise performance.

The practical takeaway is modest. If you feel foggy or irritable by mid-afternoon, how much you have had to drink is a sensible first thing to check.

How to Meet Your Daily Water Intake With One Refillable Bottle

You do not need 10 or 20 bottles. You need one you like carrying. Across ICMR-NIN's ranges for Indian adults, a day's drinking water comes to roughly 3 to 8 fills of a 500 ml bottle, or about 1.5 to 4 fills of a 1 litre bottle. The easiest way to get there is to attach each refill to something you already do.

• Before you sit down to work: fill the bottle and keep it where you can see it. Finish it before lunch.
• At lunch: refill, and have a drink with the meal as well.
• At your tea or coffee break: refill again, and finish it before you leave.
• When you get home: one more fill covers dinner and the evening.
• Extra refills: for hot days, workouts, long commutes, or physical work.

A 1 litre bottle shortens the list. Two to four fills do the same job.

Sip steadily through the day instead of drinking large amounts at once. Very large volumes can overwhelm the kidneys' ability to clear the extra water, so spreading your refills out is both safer and easier to keep up.

Don't Like Plain Water? Other Ways to Meet Your Daily Water Intake

• Count the water in what you already have. Soup, milk, tea and coffee all add to your daily water intake, and roughly 20 percent of it comes from food. Warm options are handy when cold weather makes chilled water less appealing.
• Use Indian rehydrating drinks on hot days. Buttermilk, lemon water, lassi and torani (rice water) all help you rehydrate. Keep the added sugar low.
• Choose water over sweetened drinks most of the time. Sweetened drinks add calories, and Indian dietary guidelines advise avoiding beverages with added sugars.
• Add flavour, not sugar. A slice of lemon, some cucumber or a few mint leaves in the bottle can make plain water easier to finish.

Does Your Water Bottle Matter? A Reusable Glass Bottle for Daily Refilling

A bottle does not change how much water you need. What it changes is how easy it is to refill, and refilling is what keeps your daily water intake on track. It also keeps single-use plastic bottles out of your day, which is what Kleear was built to help with.

The Kleear 500 ml High End Borosilicate Glass bottle with silicone sleeve and bamboo lid suits daily refilling:

• 100% borosilicate glass in a 500 ml size, with a wide mouth that makes filling and cleaning easier.
• Available in six colours.
• A silicone sleeve for a comfortable grip, which also protects your hand when the drink is hot.
• Safe for hot and cold drinks, so it works for chilled water in summer and warm water in winter.
• A bamboo lid with a holding strip. The bottle is light enough for a backpack, gym bag or car cup holder.
• Dishwasher safe (bottle on the top rack). The sleeve comes off for cleaning, and the bamboo lid is best washed by hand.
• Heat-resistant but not insulated, so cold water warms up gradually over the day. Starting with chilled water helps.

Shop the Kleear 500 ml bottle with Silicone sleeve and Bamboo Lid here.

Want Fewer Refills? A 1 Litre Borosilicate Glass Bottle for Daily Water

If refilling is the part of the routine you like least, a 1 litre bottle covers a day's water in fewer trips: about 1.5 to 4 fills across ICMR-NIN's ranges for Indian adults.

The Kleear 1 litre High End Borosilicate Glass bottle has no sleeve, which makes it simple to see how much you have had and how much is left, without counting refills.

• 100% borosilicate glass in a 1 litre size.
• A bamboo lid with a holding strip, designed to give a secure, leak-proof seal.
• Heat-resistant, lightweight and dishwasher safe, with the bottle on the top rack.
• Suited to water, juices and infused drinks.

A simple routine: finish one bottle by lunch, a second by early evening, and a third on hot days or if your work is physical.

Shop the Kleear 1 litre bottle with Bamboo Lid here.

Who Needs a Different Daily Water Intake?

Babies, pregnant women, children, older adults and people with some health conditions need different amounts of water from healthy adults.

• Babies under six months who are exclusively breastfed do not need water, even in hot weather.
• Pregnancy: ICMR-NIN puts the water needed from drinks at 2.1 to 3.2 litres a day, depending on the work you do, with tea and coffee kept low. Your doctor can confirm the right amount for you.
• Children and teenagers need more per kilo than adults. The ICMR-NIN figures are above 60 ml per kg for young children, 47 to 60 for adolescent boys and 39 to 49 for adolescent girls.
• Older adults: the ICMR-NIN figure is 33 ml per kg for a sedentary day and 38 ml per kg for a moderately active one.
• Kidney disease, heart disease or certain medicines (water pills, some antidepressants, some pain medicines) raise the risk of dangerously low blood sodium. Ask your doctor before changing how much you drink.
• Long endurance events: drink only as much as you lose in sweat, and let thirst guide you.

Frequently Asked Questions 

1. How much water do I need in a day in India?

For a healthy adult, ICMR-NIN's figures work out to roughly 1.5 to 3.8 litres from drinks a day, depending on body weight and activity. That is about 1.5 to 4 fills of a 1 litre bottle. Hot days, cold weather, pregnancy and some health conditions change the number.

2. How do I calculate how much water I need by body weight?

Multiply your weight in kilograms by 32 to 58 if you are a man or 27 to 52 if you are a woman. Use the lower end for desk-based days and the higher end for physical work, then adjust for your climate.

3. Is 8 glasses of water a day enough?

Eight glasses is an easy habit, not a rule. There is no one daily water intake for everyone, and needs vary with weight, age, activity level and health. Use your own range together with your urine colour and your thirst.

4. Do chai and coffee count toward my daily water intake?

Mostly, yes. There is no convincing evidence that caffeine causes lasting water deficits, and in a trial of 72 men, tea and coffee did not differ from water in urine output over the following four hours. During pregnancy, keep tea and coffee low.

5. Can you drink too much water?

Yes. Drinking excessive amounts of water can overwhelm the kidneys' ability to excrete it, which dilutes the sodium in the blood (hyponatremia). Symptoms include nausea, headache, confusion and fatigue. This is why refills are best spread through the day, with thirst and urine colour as your guide.

6. How much water should I drink in hot or humid weather?

• Very active people and people in hot climates may need more than the reference figures.
• On very hot days, drink water whenever possible, even if you are not thirsty, and carry water when you travel.
• In humid weather, sweat evaporates less easily, so keep sipping and include ORS, buttermilk or lemon water on the hottest days.
• For people working in the heat, a cup of water every 20 minutes or more often is advised.
• If you feel faint or ill, see a doctor or health centre straight away.

7. Do I need less water in cold weather or at high altitude?

Not necessarily. Cold reduces thirst by up to 40 percent, so it is easy to drink too little even when your body needs fluid. Warm drinks count, so sip at regular intervals and use your urine colour as a check. At high altitude, drink steadily and do not force extra water: it does not prevent altitude illness and can lower blood sodium. If you are travelling to a high-altitude region, ask your doctor about altitude illness before you go.

8. What is an IMD heat wave, and should I drink more water during one?

The India Meteorological Department declares a heat wave when the maximum temperature reaches at least 40°C on the plains, 37°C at coastal stations or 30°C in hilly regions, and also runs well above normal or reaches 45°C on the plains. During a heat wave, India's health advisories say to drink water whenever possible, even if you are not thirsty, and to carry water when you travel.

9. How often should I refill my water bottle?

Count refills against your range. That is roughly 3 to 8 fills of a 500 ml bottle a day, or about 1.5 to 4 fills of a 1 litre bottle. Tie each refill to something you already do, like starting work, lunch and your tea or coffee break.

10. Does it matter what my water bottle is made of?

Not for how much you need to drink. What matters is that you carry it, refill it and can clean it easily. If you prefer glass, Kleear's High End Borosilicate Glass range includes the 500 ml bottle used in this post, and a 1 litre bottle with a bamboo lid for fewer refills.

Disclaimer

This post is for general information and is not medical advice. Please do not make any serious change to your lifestyle, including how much you drink, eat or exercise, without consulting your doctor first. If you have a medical condition, are pregnant or take regular medication, speak to your doctor before changing how much water you drink.

Sources

Daily water needs in India

• ICMR-National Institute of Nutrition (2020). Nutrient Requirements for Indians: Recommended Dietary Allowances and Estimated Average Requirements, short report. Water required from drinks in ml per kg body mass for men, women, children, adolescents, older adults and pregnant women, and the 65 kg and 55 kg reference weights. The full report is listed on NIN's publications page.
• ICMR-National Institute of Nutrition (2024). Dietary Guidelines for Indians. Guideline 14 on drinking an adequate quantity of water, the advice to avoid beverages with added sugars (Guideline 1), fluid advice during pregnancy (Guideline 2), and the advice that exclusively breastfed infants under six months need no water (Guideline 3).
• US National Academies of Sciences, Engineering, and Medicine (2004). Report sets dietary intake levels for water, salt and potassium to maintain health and reduce chronic disease risk. The 3.7 litre and 2.7 litre total water figures, the temperate climate assumption, and the finding on caffeine and water balance.
• The same release as reproduced by ScienceDaily (12 February 2004). Let thirst be your guide. The 80 percent drinks and 20 percent food split.
• MedlinePlus, US National Library of Medicine. Water in diet. Soup, milk, tea and coffee contribute to total water, and water is a better choice than sweetened drinks.

IMD ranges, heat, humidity and cold in India

• India Meteorological Department, via the National Centre for Disease Control. Heat wave vulnerable areas and early warning system of IMD. Heat wave and warm night criteria (thresholds of 40°C, 37°C and 30°C, departure from normal, and actual maximum temperature), where heat waves occur, the users IMD sends warnings to, the twice-daily heat wave bulletins and the three tiers of impact-based heat warnings.
• Ministry of Health and Family Welfare, National Centre for Disease Control. Public Health Advisory: Cold Wave/Frost. IMD's cold wave and severe cold wave criteria, the November to March season, the 17 states and union territories in the core cold wave zone, and district-wise warnings updated every four hours on mausam.imd.gov.in.
• Business Standard. From red to orange: What do IMD's colour-coded weather alerts mean? The four IMD alert colours and what each means.
• Ministry of Health and Family Welfare, National Centre for Disease Control. Public Health Advisory: Extreme Heat/Heatwave. Drinking water on hot days even without thirst, thirst not being a good indicator of dehydration, carrying water, and regular water breaks for people working in the heat.
• National Disaster Management Authority, as published by the India Meteorological Department. Heat stress: Do's and Don'ts. ORS and homemade rehydration drinks such as lassi, torani, lemon water and buttermilk, and avoiding the sun between 12 noon and 3 pm.
• Down To Earth (2019). Blazing India: 22 states see 73 heatwave spells in 97 days. Humidity compounding heat in coastal and eastern states, and raising the felt temperature and sweating.
• Millennium Post (24 April 2024), reporting the India Meteorological Department's bulletin. Intense heatwave sweeps East India, spreads to South. High humidity across coastal and northeastern states, and warm nights preventing the body from cooling down.
• Directorate General of Health Services, Delhi. Public Health Advisory: Protect yourself from cold wave. The advice to drink warm fluids regularly.

Heat, cold and altitude: the physiology

• National Institute for Occupational Safety and Health (2017). Heat Stress: Hydration. DHHS (NIOSH) Publication No. 2017-126. Drinking before you feel thirsty in the heat.
• Tanen D. Merck Manual Professional Version (reviewed March 2023). Overview of Heat Illness. How humidity limits cooling through sweat, and why enough fluid and sodium helps prevent heat illness.
• Kenefick RW, Hazzard MP, Mahood NV, Castellani JW (2004). Thirst sensations and AVP responses at rest and during exercise-cold exposure. Medicine & Science in Sports & Exercise, 36(9), 1528 to 1534. Cold exposure reduced thirst by up to 40 percent, in both hydrated and dehydrated states.
• University of New Hampshire. Why we feel less thirsty in the cold. Fluid deficits of 3 to 8 percent of body mass reported in people working in cold environments.
• American Family Physician (2020). Acute Altitude Illness: Updated Prevention and Treatment Guidelines from the Wilderness Medical Society. 101(8), 505 to 507. Altitude risk above 2,500 metres, and forced overhydration not preventing altitude illness while raising the risk of hyponatremia.

Checking your hydration

• Guy's and St Thomas' NHS Foundation Trust. Keeping hydrated. Urine colour and smell as signs of dehydration.
• NHS Scotland (March 2022). Spotting the signs of dehydration. The note that some medicines affect urine colour.
• Mayo Clinic. Hyponatremia. Risks and symptoms of drinking too much water, the conditions and medicines that raise the risk, advice for athletes, and thirst and urine colour as guides.

Research

• Ganio MS et al. (2011). Mild dehydration impairs cognitive performance and mood of men. British Journal of Nutrition, 106(10), 1535 to 1543. Trial of 26 healthy young men.
• Effect of mild dehydration on cognitive function, mood and exercise performance. Cambridge Core. A smaller study that found no effect on cognitive function.
• Maughan RJ et al. (2016). A randomized trial to assess the potential of different beverages to affect hydration status: development of a beverage hydration index. American Journal of Clinical Nutrition, 103(3), 717 to 723. Trial of 72 men comparing tea, coffee and other drinks with water.