Introduction
In 2020, over 355,000 new cases of oral cavity cancer (OCC) were diagnosed worldwide, resulting in nearly 177,000 deaths. Historically, OCC has primarily affected older males exposed to traditional risk factors such as tobacco, alcohol, and betel nut chewing. As the use of tobacco declines in countries with anti-tobacco campaigns, smoking-related OCC has decreased in high-resource nations. However, in the past three decades, there has been an increased incidence of OCC among nonsmokers. The cause of OCC in nonsmokers is not associated with human papillomavirus and remains unknown.
The Western diet, characterized by high intake of saturated fats, processed food, and added sugars, is increasingly recognized as a risk factor for gastrointestinal tract cancers. The consumption of added sugars, a component of the Western diet, has increased. Despite public health recommendations and guidelines from the World Health Organization advising that added sugars be limited to 5% of calories, consumption remains excessive in many countries.
Added sugar intake and sugar-sweetened beverage (SSB) intake have been associated with a greater prevalence of periodontal disease in young adults. Periodontal disease has been associated with OCC. While this association does not imply causality, diets high in added sugar may contribute to chronic inflammation, which could, in turn, increase the risk of OCC.
Objective
This study evaluated the association between SSBs and risk of OCC among smoking and nonsmoking females participating in two large prospective cohort studies.
Methods
This longitudinal cohort study analyzed data from the Nurses’ Health Study (NHS) and Nurses’ Health Study II (NHSII), after excluding those with a history of cancer, implausible caloric intake, or missing SSB intake data. Follow-up occurred until the diagnosis of OCC. Data analysis was performed from July 2023 to June 2024.
Results
A total of 162,602 females were evaluated. During the 30 years of follow-up, 124 invasive OCC cases were documented. Participants consuming one or more SSB daily had a 4.87 times higher risk of OCC compared with those consuming less than one SSB monthly. This association was present after adjusting for tobacco, alcohol use, BMI, and glycemic load. When restricted to nonsmokers or light smokers and nondrinkers or light drinkers, OCC risk with one or more SSB consumed per day was 5.46 times higher than in those who consumed less than one SSB monthly
Conclusions
In this study high SSB intake was associated with a significantly increased risk of OCC in females, regardless of smoking or drinking habits, yet with low baseline risk. A stronger association was found in nonsmoking and light-smoking as well as nondrinkers and light drinkers. The findings support observational and mechanistic evidence indicating that dietary sugars may have a local impact on OCC, similar to associations found in other gastrointestinal site cancers. This study underscores the importance of limiting sugar intake to improve overall health and reduce the risk of chronic diseases in the general population. Further research in larger cohorts, including males, is necessary to validate these findings.
