Department of Community Health Sciences, Faculty of Medicine, University of Calgary, 3rd Floor, TRW Building, 3280 Hospital Dr, NW, Calgary, Alberta T2N 4Z6, Canada.
Int J Equity Health. 2014 Jun 5;13:44. doi: 10.1186/1475-9276-13-44.
In many countries including Canada, excess consumption of dietary sodium is common, and this has adverse implications for population health. Socio-economic inequities in sodium consumption seem likely, but research is limited. Knowledge of socio-economic inequities in sodium consumption is important for informing population-level sodium reduction strategies, to ensure that they are both impactful and equitable.
We examined the association between socio-economic indicators (income and education) and sodium, using two outcome variables: 1) sodium consumption in mg/day, and 2) reported use of table salt, in two national surveys: the 1970/72 Nutrition Canada Survey and the 2004 Canadian Community Health Survey, Cycle 2.2. This permitted us to explore whether there were any changes in socio-economic patterning in dietary sodium during a time period characterized by modest, information-based national sodium reduction efforts, as well as to provide baseline information against which to examine the impact (equitable or not) of future sodium reduction strategies in Canada.
There was no evidence of a socio-economic inequity in sodium consumption (mg/day) in 2004. In fact findings pointed to a positive association in women, whereby women of higher education consumed more sodium than women of lower education in 2004. For men, income was positively associated with reported use of table salt in 1970/72, but negatively associated in 2004.
An emerging inequity in reported use of table salt among men could reflect the modest, information-based sodium reduction efforts that were implemented during the time frame considered. However, for sodium consumption in mg/day, we found no evidence of a contemporary inequity, and in fact observed the opposite effect among women. Our findings could reflect data limitations, or they could signal that sodium differs from some other nutrients in terms of its socio-economic patterning, perhaps reflecting very high prevalence of excess consumption. It is possible that socio-economic inequities in sodium consumption will emerge as excess consumption declines, consistent with fundamental cause theory. It is important that national sodium reduction strategies are both impactful and equitable.
在包括加拿大在内的许多国家，饮食中钠的摄入量过高是很常见的，这对人群健康有不利影响。钠摄入量的社会经济不平等似乎是可能的，但研究有限。了解钠摄入量的社会经济不平等对于为人群层面的钠减排策略提供信息非常重要，以确保这些策略既具有影响力又公平。
我们使用两个结果变量检验了社会经济指标（收入和教育）与钠之间的关联：1）每天的钠摄入量（mg/天），2）报告使用食盐。在两个全国性调查中：1970/72 年加拿大营养调查和 2004 年加拿大社区健康调查，周期 2.2。这使我们能够探索在以信息为基础的适度国家钠减排努力为特征的时间段内，饮食中钠的社会经济模式是否发生了变化，以及提供基线信息，以便检查未来加拿大钠减排策略的影响（公平与否）。
2004 年，钠摄入量（mg/天）方面没有社会经济不平等的证据。事实上，研究结果表明女性存在正相关，即 2004 年，受过高等教育的女性比受过较低教育的女性摄入更多的钠。对于男性，1970/72 年，收入与报告使用食盐呈正相关，但 2004 年呈负相关。
在考虑的时间段内实施了适度的、基于信息的钠减排措施，男性报告使用食盐的情况出现了新的不平等。然而，对于每天的钠摄入量，我们没有发现当代不平等的证据，实际上我们观察到女性的相反效果。我们的研究结果可能反映了数据的局限性，也可能表明钠在社会经济模式方面与其他一些营养素不同，这可能反映了过量摄入的极高流行率。随着过量摄入的减少，钠摄入量的社会经济不平等可能会出现，这与根本原因理论一致。重要的是，国家钠减排策略既要有影响力又要公平。
