The time trend of information seeking behavior about salt reduction using Google Trends: infodemiological study in Japan.

Numerous initiatives have been implemented to reduce salt intake to prevent hypertension and cardiovascular disease. However, salt consumption remains high. No study worldwide has evaluated the public's awareness of salt reduction by analyzing Internet research activity. This research aims to assess trends in the public's attention to salt reduction using Google Trends. We evaluated the relative search volume (RSV) of "salt reduction" in Google Trends from January 1, 2004, to December 31, 2021. Regression coefficients indicated that RSVs increased 0.0091 (95% CI, 0.0085-0.0097, p < 0.001) per year for salt reduction. Among related search terms, search for "salt component," "soy sauce," and "pickled plum" contributed to 9.9 ± 3.2%, 5.8 ± 2.0%, and 3.9 ± 5.5% of total RSVs for salt reduction. Google Trends revealed that the Japanese public's awareness of salt reduction has increased. Related searches might provide insights when people search for salt reduction, which could be helpful for future effective interventions for understanding salt reduction. The trends of Relative search volumes (RSVs) for "salt reduction" and "salt reduction filtered" have significantly increased RSV in 2021 compared to 2004. Google Trends is an effective tool for salt reduction awareness research that provides large amounts of real-time search data.