It’s no secret that water is vital to your health.
In fact, water comprises 45–75% of your body weight and plays a key role in heart health, weight management, physical performance, and brain function (1Trusted Source).
Studies show that upping your water intake may offer many health benefits (2Trusted Source).
However, the amount of water you need is a subject of controversy — and drinking too much can harm your health.
This article examines the benefits and downsides of drinking 3 liters (100 ounces) of water per day.
Supports overall health
Staying well hydrated is incredibly important, as water is needed for a variety of bodily processes and central to nearly every aspect of health and wellness.
In particular, this fluid helps regulate body temperature, transport nutrients, maintain brain function, and enhance physical performance (3Trusted Source).
Not getting enough water can be detrimental, potentially causing side effects like nausea, fatigue, constipation, headaches, and dizziness (4 Trusted Source).
Therefore, drinking 3 liters (100 ounces) of water per day may help you meet your hydration needs to support better health.
Summary: Drinking enough water is important for many aspects of health, including body temperature, nutrient transport, and brain function.
Boosting weight loss
Increasing your water intake may aid weight loss.
Drinking water just before meals can be especially useful, as it can promote feelings of fullness and reduce appetite.
One study in 24 people found that drinking 500 ml (17 ounces) of water before breakfast reduced the number of calories consumed by 13% (5Trusted Source).
Similarly, a small, 12-week study showed that drinking 500 ml (17 ounces) of water before each meal as part of a low-calorie diet increased weight loss by 44%, compared with a control group (6Trusted Source).
Drinking water may also temporarily boost your metabolism, which can increase the number of calories you burn throughout the day.
In a small study in 16 people, drinking 500 ml (17 ounces) of water temporarily increased metabolism by 24% over 1 hour, which may aid weight loss (7Trusted Source).
Summary: Water may help you feel full and temporarily increase your metabolism, which may bolster weight loss.
May improve skin health
Some research suggests that drinking more water can help keep your skin supple and smooth.
For example, a month-long study in 49 people determined that increasing water intake by 2 liters (67 ounces) per day improved skin hydration, especially in those who typically drank under 3.2 liters (108 ounces) of water daily (8Trusted Source).
Another study in 40 older adults linked higher fluid intake to increased skin hydration and skin surface pH (9Trusted Source).
Skin pH plays an integral role in maintaining your skin’s barrier, which can influence your risk of certain skin conditions (10).
Additionally, a review of six studies found that increased water intake reduced dryness and roughness, increased skin elasticity, and enhanced hydration (11Trusted Source).
Summary: Drinking more water may promote healthy skin by increasing hydration and elasticity while reducing roughness and dryness.
Other benefits
Drinking more water may offer several other benefits as well, including:
- Increased regularity. Multiple studies associate low water intake with a higher risk of constipation. As such, drinking more water may promote bowel movements (12Trusted Source).
- Kidney stone prevention. One review of nine studies tied higher fluid intake to a lower risk of kidney stones (13Trusted Source).
- Headache relief. Research suggests that drinking more water can alleviate headaches caused by dehydration or fluid loss (14Trusted Source, 15Trusted Source).
- Mood improvement. According to one review, increasing water intake may aid both brain function and mood, especially in children and older adults (16Trusted Source).
- Enhanced athletic ability. While dehydration can impair exercise performance, replacing fluids after physical activity can increase endurance and decrease exercise-induced DNA damage (17Trusted Source).
Summary: Drinking 3 liters (100 ounces) of water per day may aid bowel regularity, prevent kidney stones, alleviate headaches, improve mood, and strengthen physical performance.
-health line.com