Sodium content of restaurant dishes in China: a cross-sectional survey

Background Sodium intake in China is extremely high and eating in restaurants is increasingly popular. Little research has explored the sodium level of restaurant dishes. The present study aims to assess the content and sources of sodium in Chinese restaurants. Methods Cross-sectional data were obtained from the baseline survey of the Restaurant-based Intervention Study (RIS) in 2019. A total of 8131 best-selling restaurant dishes with detailed recipes from 192 restaurants in China were included. Sodium content per 100 g and per serving were calculated according to the Chinese Food Composition Table. The proportion of restaurant dishes exceeding the daily sodium reference intake level in a single serving and the major sources of sodium were determined. Results Median sodium content in restaurant dishes were 487.3 mg per 100 g, 3.4 mg per kcal, and 2543.7 mg per serving. For a single serving, 74.9% of the dishes exceeded the Chinese adults’ daily adequate intake for sodium (AI, 1500 mg per day), and 62.6% of dishes exceeded the proposed intake for preventing non-communicable chronic diseases (PI, 2000 mg per day). Cooking salt was the leading source of sodium in Chinese restaurant dishes (45.8%), followed by monosodium glutamate (17.5%), food ingredients (17.1%), soy sauce (9.4%), and other condiments/seasonings (10.2%). More types of salted condiments/seasonings use were related to higher sodium level. Conclusions The sodium levels in Chinese restaurant dishes are extremely high and variable. In addition to cooking salt, other salted condiments/seasonings also contribute a large proportion of sodium. Coordinated sodium reduction initiatives targeting the main sources of sodium in restaurant dishes are urgently needed.