**Background:** Dietary sodium intake is a critical lifestyle factor for cancer survivors, who face elevated risks of adverse health outcomes including cardiovascular disease and mortality. However, the relationship between sodium intake and impaired fasting glucose (IFG)—a prediabetic state that can progress to type 2 diabetes—remains poorly characterized in this population. The American Heart Association (AHA) recommends limiting sodium to <2,300 mg/day, with an ideal limit of <1,500 mg/day. This study aimed to investigate the association between dietary sodium intake categorized by AHA recommendations and IFG among community-dwelling adult cancer survivors.
**Methods:** Data were drawn from the sixth and seventh Korea National Health and Nutrition Examination Survey (KNHANES), 2013–2018, a nationally representative surveillance project. From 1,632 adult cancer survivors, 1,052 were included after excluding those with type 2 diabetes (n=249), missing dietary data (n=101), missing glycemic data (n=78), or missing covariate data (n=152). Dietary sodium intake was assessed via a self-administered 24-hour recall and categorized as <1,500 mg/day, 1,500–2,299 mg/day, 2,300–3,999 mg/day, and ≥4,000 mg/day. IFG was defined as fasting plasma glucose of 100–125 mg/dL or HbA1c of 5.7%–6.4%, per Korean Diabetes Association criteria (aligned with ADA guidelines). Covariates included age, sex, education, household income, smoking, alcohol, physical activity, waist circumference, blood pressure, lipid profile, total energy intake, and macronutrient/potassium intake. Survey-weighted multiple logistic regression was used to compute adjusted odds ratios (OR) and 95% confidence intervals (CI), with restricted cubic spline analysis for dose-response visualization.
**Key Results:** Among 1,052 adult cancer survivors, only 16.6% consumed <1,500 mg/day of sodium. The median (IQR) sodium intakes across categories were 1,093 mg/day (793–1,323), 1,878 mg/day (1,694–2,101), 2,995 mg/day (2,644–3,449), and 5,192 mg/day (4,409–6,461), respectively. Overall, 583 participants (55.4%) had IFG. In the fully adjusted model (Model 3: age, sex, physical activity, household income, education, smoking, alcohol, total energy, fat, protein, carbohydrate, and potassium intake), the ORs for IFG compared to <1,500 mg/day were: 1.16 (95% CI: 0.25–5.27) for 1,500–2,299 mg/day; 1.93 (95% CI: 0.40–9.37) for 2,300–3,999 mg/day; and 2.67 (95% CI: 0.59–12.18) for ≥4,000 mg/day. While individual category estimates were not statistically significant, the linear trend across categories was significant (P for trend = 0.036). Restricted cubic spline plots showed marginally increasing odds of IFG around 2,500–3,000 mg/day. Higher sodium intake was associated with younger age, male sex, higher income, higher education, and greater total energy and nutrient intake.
**Clinical Implications:** This study provides preliminary evidence that dietary sodium intake above AHA-recommended levels may be associated with higher odds of IFG in adult cancer survivors, with a dose-response trend. Given that IFG is linked to a 13% increase in all-cause mortality and a 15% increase in composite cardiovascular outcomes in the general population, and may be associated with secondary primary cancer risk in survivors, glycemic management through sodium restriction warrants attention. However, the study has important limitations: the cross-sectional design precludes causal inference; the sample was relatively small (n=1,052) and limited to Korean adults; dietary sodium was assessed via single 24-hour recall without validation; and confidence intervals were wide, reflecting imprecision. The authors appropriately conclude that well-designed prospective cohort studies or randomized trials in ethnically diverse populations are needed to establish more robust evidence before clinical recommendations can be made.