It is important to be clear that plain water is the best form of hydration. Beverages that contain calories, sugar, dyes, and flavors are not optimal sources of hydration. That being said, even all plain water is not created equal, the best source of plain water is alkaline hydroxide rich water (my personal favorite is AQUA-OH!). The hydroxide (OH-) in the water searches out and combines with Hydrogen ions (H+) which cause acidity and inflammation. It also creates more water than you actually drink (H+ plus OH- = H2O). This is called ultra-hydration.
The average person should consume at least half of their body weight in ounces of water per day (i.e. A 150 lb. person should aim to consume at least 75 fl.oz. of water per day.) As stated above plain alkaline hydroxide water is the best source of water for hydration but there are some other beverages that can count towards your daily hydration goal.
Sport drinks count toward your daily hydration goal but they also come with additional calories, sugar and dyes, that can contribute to increased insulin and blood sugar levels and over time they will increase your chance for gaining weight.
Sodas/Colas do not count towards daily hydration goal; the chemicals and carbonation can hinder the body from absorbing the liquid for hydration.
Alcohol does not count towards hydration because just like soda/cola it hinders the body’s ability to absorb the liquid for hydration. Alcohol beverages actually dehydrates us.
Coffee/tea with caffeine is a natural diuretic so these calorie free options are healthy in other ways for their antioxidant and digestion benefits but they are not hydrating.
Caffeine free tea, juice and milk can count toward your daily hydration goal because they do not have diuretic properties, but these options should only be a small portion of your liquid consumption over the course of the day (20-25% total liquid goal). It is best to consume most of your liquids from plain alkaline hydroxide water.