Overview

• Reusable water bottles can host millions of bacteria, with spout-lid designs containing up to 30 million colony-forming units (CFUs), according to research by WaterFilterGuru.
• Gram-negative bacteria, which are resistant to antibiotics, and bacillus bacteria, linked to gastrointestinal issues, are commonly found in bottles, particularly straw-lid designs.
• Health experts recommend washing bottles daily with warm, soapy water and deep cleaning weekly using vinegar, baking soda, or dishwasher cycles for optimal hygiene.
• Moist environments inside bottles foster bacterial growth; experts stress the importance of fully air-drying bottles and emptying stagnant water when not in use.
• Stainless steel bottles are advised over plastic due to their reduced bacterial adhesion, while lids, seals, and threads require thorough cleaning to eliminate hidden germs.