Water is essential for life survival and development. It plays a pivotal role in metabolic function, modulates normal osmotic pressure, maintains the electrolyte balance, and regulates body temperature. Adequate water intake is necessary for optimal hydration-both excessive and insufficient water consumption can have adverse effects on health. Water requirements among people vary based on various factors such as gender, age, physical activity, dietary factors, ambient temperature, and renal concentrating capacity. In recent years, water intake guidelines have been developed in some countries and by some organisations. Even in China, it is important to develop such guidelines considering specific dietary habits, height of people, and environmental factors. In 2013, guidelines for adequate water intake were developed in China, but the scope was somewhat limited; there are still specific challenges in formulating such recommendations. Future water-related studies should focus on surveying water intake among infants and toddlers, older adults, and pregnant and lactating women. Moreover, additional studies should be conducted to elucidate water intake among adults and adolescents in different regions and seasons, and the association between water intake and related diseases should also be investigated. It is imperative to transform the results of scientific research into action plans for water-related health education so as to inform and evaluate pertinent public health programmes.