Background: Accurate and precise estimates of discretionary salt intake are critical for the design of salt fortification programs and salt reduction interventions.

Objectives: This study aimed to compare 4 methods of estimating discretionary salt intake among nonpregnant females of reproductive age in Punjab, India.

Methods: One-day, observer-recorded, weighed food records (WFRs), household salt disappearance (HHSD) data, duplicate diet composites, and samples of household salt and milk were collected from 100 females and repeated in a subset of 40 to adjust for intraperson variation and estimate usual discretionary salt intake. Diet composites were also replicated from 40 randomly selected WFR but prepared without the addition of discretionary salt. The duplicate diet composites' sodium and iodine contents were analyzed using inductively coupled plasma (ICP)-optical emission spectrometry and ICP-mass spectrometry, respectively. The iodine content of household salt samples was analyzed using the ion-selective electrode method. The association and agreement between the WFR method, the selected reference method, and the HHSD, replicate diet (RD), and iodine methods (IMs) were explored using correlation and Bland-Altman analyses.

Results: Mean ± standard deviation (SD) discretionary salt intakes according to the WFR, HHSD, RD, and IM methods were 4.7 ± 1.8 g/d, 5.7 ± 2.6 g/d, 4.1 ± 2.1 g/d, and 7.8 ± 5.3 g/d, respectively. The RD method showed the strongest correlation (ρ = 0.76; P < 0.001) and the smallest mean difference ± SD (-0.68 ± 1.25 g/d), with limits of agreement from -3.18 to 1.82 g/d, compared with the WFR method. However, the HHSD method was also moderately correlated (ρ = 0.48; P < 0.001) and showed good agreement [0.98 ± 2.12 (-3.27, 5.23) g/d] with the WFR despite lower precision.

Conclusions: Although intensive to implement, the WFR and RD methods produce precise estimates of discretionary salt intake. Repeated measurements may improve the precision of the HHSD method for large population-based surveys.

Keywords: India; dietary assessment; discretionary salt intake; fortification; nonpregnant females of reproductive age; salt intake; sodium intake.

© 2025 The Author(s).

背景: 准确且精确地估算自由添加食盐摄入量对于设计食盐强化项目和减少食盐摄入的干预措施至关重要。

目的: 本研究旨在比较在印度旁遮普邦非孕期育龄女性中估计自由添加食盐摄入量的4种方法。

方法: 从100名女性那里收集了一天内的观察记录和称重食物记录（WFRs）、家庭食盐消耗数据（HHSD），重复膳食样本以及家庭食盐和牛奶样本。在一组40人中重复采集以调整个体内部差异并估算通常的自由添加食盐摄入量。还从40名随机选择的WFR女性那里复制了饮食样本，但未加入自由添加的食盐。使用电感耦合等离子体（ICP）-光学发射光谱法和ICP-质谱法分别分析重复膳食样品中的钠和碘含量；使用离子选择电极法分析家庭食盐样品中的碘含量。采用相关性和Bland-Altman分析探讨WFR方法与选定参考方法、HHSD、复制饮食（RD）以及碘测定（IMs）之间的关联及一致性。

结果: 根据WFR、HHSD、RD和IM方法，平均±标准差的自由添加食盐摄入量分别为4.7 ± 1.8克/天、5.7 ± 2.6克/天、4.1 ± 2.1克/天和7.8 ± 5.3克/天。与WFR方法相比，RD方法显示出最强的相关性（ρ = 0.76；P

结论: 虽然实施起来较为繁琐，但WFR和RD方法能产生精确的自由添加食盐摄入量估计。重复测量可能会提高大规模人群调查中HHSD方法的精度。

关键词: 印度；膳食评估；自由添加食盐摄入量；强化；非孕期育龄女性；食盐摄入；钠摄入。