How Much Water Should I Drink a Day?

The simple formula

A good starting point is half your body weight in pounds, in ounces of water per day. A 160 lb person starts at 80 oz, then adjusts up for activity, heat, or caffeine.

Adjustments to make

• Exercise: add 8–16 oz per 30 minutes
• Hot climate: add 16–24 oz
• Caffeine or alcohol: add 8 oz per serving
• High fiber or protein diet: add 8–16 oz

Signs you''re not drinking enough

• Dark urine
• Headaches or fatigue
• Dry skin or lips
• Constipation
• Dizziness when standing

Can you drink too much?

Yes, but it''s rare for healthy adults. Drinking far beyond thirst can dilute blood sodium. For most people, the bigger problem is under-hydration, not over-hydration.

How to build the habit

• Drink 16 oz first thing in the morning
• Keep a bottle nearby all day
• Pair water with meals
• Track it in Phoenix until the habit is automatic