Quick Answer
Drinking 5 litres (around 1.3 gallons) of water per day is typically not recommended or necessary for most healthy adults. The recommended daily fluid intake is around 2-3 litres per day for women and 2.5-4 litres per day for men. Drinking significantly more water than your body needs can potentially lead to overhydration and water intoxication.
How Much Water Do You Need Per Day?
The average recommended water intake per day is:
- Women: Around 11.5 cups (2.7 litres)
- Men: Around 15.5 cups (3.7 litres)
However, water needs can vary significantly based on factors like:
- Age
- Physical activity level
- Health conditions
- Climate and environment
For example, athletes or those living in hot climates will generally need more water than sedentary individuals or those in cooler environments. Older adults also tend to require less water than younger people.
It’s best to let your thirst guide your water intake. If you’re thirsty, drink water. Drinking when thirsty allows your body to maintain the right balance of water.
Is It Safe to Drink 5 Litres of Water Per Day?
Drinking 5 litres of water per day is typically not necessary or recommended for most healthy adults.
Consuming this much water greatly exceeds the recommended daily intake and could lead to overhydration and water intoxication in some cases.
Drinking more than your kidneys can excrete can dilute the sodium content in blood to dangerously low levels. This is known as hyponatremia and can be life-threatening.
Symptoms of overhydration and hyponatremia include:
- Headache
- Fatigue
- Nausea
- Vomiting
- Muscle weakness
- Spasms
- Seizures
- Coma
Those at higher risk of overhydration include people taking certain medications like diuretics or MDMA, endurance athletes, and people with certain health conditions like heart failure.
Unless your doctor recommends high water intake for a specific health reason, aim to drink when thirsty rather than forcing yourself to drink excessive amounts.
Benefits of Drinking More Water
While 5 litres per day is likely excessive for most people, staying adequately hydrated does provide some important health benefits:
- Improves exercise performance: Dehydration can negatively impact endurance, strength and coordination.
- Boosts energy: Water helps deliver oxygen and nutrients to cells.
- Supports kidney function: Adequate hydration helps kidneys efficiently filter waste.
- Aids digestion: Water keeps digestive system functioning smoothly.
- Maintains cardiovascular health: Proper fluid levels support heart health and blood pressure.
For most healthy people, these benefits can be achieved by drinking when thirsty and choosing water over sugary beverages. You don’t need to force yourself to drink significantly above your natural thirst level.
Tips for Staying Hydrated
Here are some tips for getting adequate hydration without having to drink excessive amounts of plain water:
- Drink when thirsty rather than on a schedule.
- Choose water, seltzer, tea, or milk instead of juice and soda.
- Eat fruits and vegetables which have high water content.
- Limit alcohol and caffeine which have dehydrating effects.
- Drink extra water before, during, and after exercise.
- Assess the color of your urine. Pale yellow indicates good hydration.
Getting adequate hydration supports overall health. But there’s little evidence that continually forcing yourself to drink significantly more than thirst dictates provides additional benefits. Most healthy adults can stay well hydrated by simply responding to thirst cues and choosing water most of the time.
How Drinking Too Much Water Affects Your Body
Drinking excessive amounts of water that your kidneys can’t adequately excrete has the following effects on your body:
Electrolyte Imbalance
Consuming too much water dilutes the sodium and other electrolytes in your blood. Electrolytes help carry electrical signals across cell membranes. When they become dangerously diluted, normal nerve and muscle function is disrupted.
Brain Swelling
Excessive water intake increases the volume of blood plasma. To try to balance this, fluid moves from the blood into brain cells, causing potentially dangerous brain swelling. This is known as cerebral edema.
Fluid Buildup
As the kidneys struggle to excrete large amounts of water, some of the excess fluid moves into body tissues. This can cause swelling in the hands, feet, and limbs (peripheral edema). In severe cases, fluid accumulates in the lungs (pulmonary edema).
Heart Strain
Too much water places an added burden on the heart which has to work harder to pump diluted blood through the bloodstream. This can lead to irregular heart rhythms.
Cellular Disruption
Excessively low sodium levels in the blood (hyponatremia) can cause cells to swell and potentially burst as water moves into them to try to balance concentrations inside and outside cell membranes.
Death
In very rare cases, severely low blood sodium levels caused by excessive hydration can lead to seizures, coma, and death. Hyponatremia has killed marathon runners who drank only water during long races.
That’s why it’s important not to overdo water intake. Moderation is key for proper hydration.
Who May Need to Drink 5 Litres of Water Per Day
While downing 5 litres of water daily is unnecessary for most people, certain individuals may have higher hydration needs in specific circumstances.
Populations that may occasionally require 5+ litres of fluid per day include:
Endurance Athletes
Marathon runners, triathletes, cyclists, and other endurance athletes who compete for multiple hours at high intensity can lose several litres of sweat and fluid each hour. Consuming drinks like diluted sports beverages helps replenish what’s lost.
Military Personnel
Troops training and performing physically demanding duties in hot environments like the desert can require 5 litres or more per day to prevent dangerous heat-related illness. The fluid helps replace what’s lost through heavy sweating.
Manual Outdoor Workers
Laborers doing intensive physical work outside in hot conditions need to drink proportionally to how much fluid is lost through sweat. At times, this can add up to 4-6 litres of water or sports drinks on hot summer days.
Kidney Stone Sufferers
People prone to recurrent kidney stones are sometimes advised to drink 4-6 litres of fluid, often spread throughout the day, to help flush out the kidneys and prevent small mineral deposits from forming stones.
However, even most people in these categories likely don’t need this level of hydration on a daily basis long-term. It’s something required temporarily to replace extraordinary fluid losses.
Signs You’re Drinking Too Much Water
How can you tell if your water intake is too high? Watch for these signs of overhydration:
- Having to urinate every hour or less
- Pale, diluted urine
- Excessive thirst
- Headache
- Dizziness
- Muscle cramps
- Fatigue
- Nausea
- Vomiting
- Confusion
- Swelling in hands, feet, or limbs
If you experience any of these symptoms along with very high water intake, cut back on fluids and consult your doctor if symptoms persist.
Pay extra attention after intense or endurance exercise when sweat losses can be high. Sports drinks like Gatorade contain sodium to help replace what’s lost and are a better option than plain water during extended physical activity.
Risk Factors for Overhydration and Hyponatremia
Certain people are at increased risk of developing dangerously low sodium levels from excess water intake:
- Marathon runners
- Triathletes
- Ultra-endurance athletes
- Hikers
- Manual laborers in hot environments
- Elderly people
- Young children
- Those taking diuretics
- People with heart, liver, or kidney disease
- MDMA (ecstasy) users
- People on fluid-restrictive diets
- People with psychogenic polydipsia
Consuming over 5 litres per day when combined with sweating, use of diuretics or laxatives, or health conditions impacting hydration can be dangerous.
Seek medical help immediately if you experience headache, confusion, seizures, irregular heartbeat, or swelling after over-drinking fluids.
Healthy Water Intake Recommendations
Instead of forcing yourself to drink a set amount every day, let the following recommendations guide your water and total fluid intake:
- Drink when you feel thirsty to replenish lost fluid.
- Choose water instead of high-calorie beverages like juice, soda, and sweetened coffee and tea.
- Consume fruits and vegetables with high water content like citrus fruits, berries, cucumber, celery, and melons.
- Drink about 2-3 cups (500-700ml) of water 2-3 hours before exercise to ensure you start adequately hydrated.
- Drink to your thirst during and after exercise. Weighing yourself pre and post-workout can provide insight into fluid losses.
- Limit alcohol and caffeine intake which have dehydrating effects.
- Consider diluted sports drinks instead of just water during prolonged intense exercise for over 60-90 minutes.
- Check your urine color. Pale yellow = well hydrated. Dark yellow = time to drink more.
- Watch for signs of overhydration like having to urinate every 30-60 minutes.
Carefully monitoring hydration needs during demanding athletic events is important. But for general day-to-day hydration, drinking to satisfy your thirst is usually sufficient for most healthy adults.
Frequently Asked Questions
Is it bad to drink 5 litres of water a day?
For most people, drinking 5 litres of water per day is excessive and unnecessary. It can potentially lead to overhydration, water intoxication, and dangerously diluted sodium levels in blood. However, some extremely active people in hot climates may occasionally need this much fluid to replace sweat losses.
What happens if you drink too much water daily?
Consuming excessive water can cause low sodium hyponatremia, brain swelling, altered mental status, seizures, coma, and even death in rare cases. Watch for initial symptoms like headache, nausea, and confusion as warning signs to cut back on fluid intake.
Can you drink too much water during exercise?
Yes, it’s possible to overdrink plain water while exercising for long periods at high intensity, especially in heat. Consuming fluid well above sweat losses can dangerously reduce sodium levels. Sports drinks contain sodium and carbohydrates to help maintain electrolyte balance.
What are early signs of overhydration?
Symptoms of drinking too much water include frequent urination, pale urine, headache, dizziness, nausea, muscle cramps, fatigue, and confusion. If experienced after increasing water intake, these are signs to reduce fluid consumption.
How can you tell if your body needs more water?
Thirst, headache, tiredness, decreased urine output and dark yellow urine color can indicate dehydration and the need to drink more fluids. Most people regulate hydration best by drinking to thirst rather than forcing a set amount daily.
Should you drink water even if not thirsty?
Most people don’t need to drink unless they feel thirsty. Forcing yourself to drink on a schedule when your body doesn’t signal thirst can promote consuming more water than necessary. However, some groups like the elderly may benefit from intentionally drinking despite minimal thirst.
What are signs you are drinking enough water?
Signs of proper hydration include:
- Absence of thirst
- Sufficiently frequent, pale yellow urination
- Lack of fatigue or headaches
- Good exercise tolerance
As long as you drink to thirst and your urine is lightly colored, you are likely well hydrated without needing to closely track water intake.
How much water should you drink before exercise?
It’s recommended to drink around 2-3 cups (500-700ml) of water in the 2-3 hours before exercise to ensure you begin the activity well hydrated. Then drink to thirst as needed during and after your workout. Weighing yourself before and after exercise gives insight into fluid losses.
Should you drink water during meals?
There is no evidence that moderate water intake with meals causes any harm or impairs digestion. Large amounts may temporarily increase feelings of fullness and reduce food intake. Sipping small amounts of water, like a glass or two, is fine for most people with meals.
The Bottom Line
Here are the key takeaways on drinking 5 litres of water per day:
- Healthy water intake varies based on factors like age, gender, activity level, and climate.
- Drinking 5 litres daily exceeds the intake needed for good hydration for most people.
- Overhydration can dilute sodium levels and cause dangerous swelling in the brain or other tissues.
- Improving hydration provides benefits, but drinking substantially above thirst offers no additional advantages.
- Endurance athletes, some outdoor laborers, and specific health conditions may occasionally warrant 5+ litres to replace fluid losses.
- For most people, drinking when thirsty and choosing water routinely is sufficient for proper hydration.
While water is essential for health, more is not necessarily better. Stick within recommended guidelines for your gender and activity level, drink primarily when thirsty, and modify your intake if experiencing any symptoms of overhydration. This balanced approach will help you stay optimally hydrated.
