Two PhD candidates from the WHO CC team recently presented their research at the 27th Scientific Meeting of the International Society of Hypertension in Beijing, China.
Kathy Trieu presented findings on mean 24-hr urinary salt excretion in two regions of Kazakhstan. These populations had extremely high salt intakes, possibly the highest in the world. The two surveys were conducted by the Kazakh Academy of Nutrition in collaboration with the Ministry of Education and Science of the Republic of Kazakhstan in Almaty City in 2015, and Kyzylorda in 2016.
Mean salt intake was 17.2g/d (95% CI 16.2-18.2) in Almaty City and all (100%) participants exceeded the recommended 5g/d target. The mean intake in Kyzylorda was 18.8g/d (95% CI 17.0-20.5) and 99% of participants exceeded the 5g/d target. While these findings are not nationally representative, Kathy Trieu concluded that, “this salt intake estimate provides justification for a national multi-faceted salt reduction strategy and a baseline for which future measurements can be compared against to monitor the effects of interventions.”
Joseph Alvin Santos presented findings on the use of spot urine samples to estimate mean population salt intake in Fiji and Samoa. Mean salt intake was estimated from spot urine samples using six equations–Kawasaki, Tanaka, Mage, INTERSALT and Toft–and compared with the measured salt intake from 24-hour urine samples. 414 individuals from Fiji and 725 individuals from Samoa were included in the analyses, and it was found that salt intake based on 24-hour measures was 8.36g/day (95% CI 8.06-8.66) in the combined sample.
Mean salt intake estimates from the INTERSALT equations (with and without potassium) were within 1g/day of the estimate based on 24-hour urine, estimates from the Tanaka and Toft equations were 1-2 g/day higher, and estimates from the Kawasaki and Mage equations were >2g/day higher. All of the spot equations correctly classified mean salt intake as above the 5g/day recommendations. Joseph concluded that “the study provides support to the notion that spot urines may be used as an alternative method to estimate population-level salt intake. The INTERSALT equations gave the best estimate of mean salt intake in this population.”