What Drinking a Glass of Water First Thing in the Morning May Do for Your Energy and Digestion

After a night’s sleep, you might wake up slightly dehydrated. Even mild dehydration can contribute to low energy, fatigue and digestive issues. Drinking a glass of water in the morning can restore hydration, support digestion, and help you feel more alert as you start your day.

Hydration plays a key role in making you feel alert and focused. When you don’t drink enough fluids, it can affect blood flow to the brain. You may notice fatigue, brain fog, or difficulty concentrating.

In one study, young adults who went 12 hours without fluids had slower reaction times, greater fatigue, and poorer memory and attention than those who were well hydrated.

Another study found that drinking about two cups of water (500 milliliters) before bed and again in the morning can improve alertness and reaction speed.

If fatigue is caused by poor sleep, stress, or an existing health problem, drinking water may not make a noticeable difference. However, staying hydrated can help you feel more alert and less tired if dehydration is the cause.

Drinking water in the morning can prepare your digestive system for the day ahead. Fluids help food and waste move through the digestive tract. When you don’t drink enough, stools may move more slowly, which can lead to constipation.

Water also keeps stools soft and easier to pass. Research shows that people who consume enough fluids and water-rich foods have a lower risk of constipation, and this risk continues to decrease as their intake increases.

During digestion, your small intestine draws water from your bloodstream into your intestine to break down food.

Some people report that drinking water in the morning helps trigger bowel movements, especially when combined with physical activity or coffee. If you already drink enough fluids, you may not notice a significant difference.

Drinking water in the morning can help, but timing matters less than total fluid intake.

Most women need about 11.5 cups of water per day and men need about 15.5 cups, including fluids from drinks and food. Since foods like fruits, vegetables and soups contain water, experts suggest aiming for around nine cups of water per day for women and 13 cups for men.

Starting the day with water can give you a head start, especially if you tend to forget to drink later.

For most people, starting with a glass of water (about 8 to 16 ounces) is a good place to start. Drinking a lot at once is not necessary and may be uncomfortable.

Despite common claims, a few beliefs about morning water are not supported by research:

• Hot water stimulates metabolism: Water temperature does not significantly affect metabolism.
• Cold water is bad for digestion: There is no solid evidence that cold water affects digestion. A small study suggests that very cold water may slow stomach movements and reduce appetite, but research is limited. Cold water and room temperature water hydrate the body equally.
• Drinking more than you need adds benefits: Once your hydration needs are met, excess water provides no additional health benefits. In rare cases, drinking too much water can dilute sodium levels and disrupt the body’s normal fluid balance.

Additionally, some people need to limit their fluid intake. If you have heart failure, kidney disease, or have been told to limit your fluid intake, talk to a healthcare professional about how much you should drink.

For most healthy adults, drinking to quench their thirst is a good rule of thumb. Pale yellow urine usually means you are well hydrated. Dark urine may indicate a need for more fluids.

Some people are more likely to notice the benefits of morning hydration.

Can benefit the most:

• People who don’t drink enough fluids
• Those who are prone to constipation
• People who wake up lethargic
• Older people who may not feel thirst as strongly

May notice little difference:

• People who already meet their daily hydration needs
• Those who drink most of their fluids late in the evening
• People whose fatigue is linked to sleep or health problems

Small habits, like starting the day with water, can make it easier to stay hydrated. If plain water seems boring, try adding lemon, sipping herbal tea, or eating water-rich foods like fruit to help you stay hydrated.