Doctors are calling it a simple health habit that can dramatically improve your day. Drinking a glass of water right after waking up helps kickstart your metabolism, flush toxins, and rehydrate your body after hours of sleep.

Many people underestimate how dehydrated they are when they wake up. Even mild dehydration can affect energy levels, focus, and mood. Starting your day with water not only energizes you but also helps your digestive system and can even improve your skin.

Some experts suggest adding lemon for an extra boost of vitamin C and a refreshing taste. This small routine takes less than a minute but has effects that last all day.

Hydration may be one of the easiest ways to improve health without spending money or changing your routine drastically. Start tomorrow morning—you might be surprised by the difference.