Low-salt diets may only be beneficial for people with high blood pressureBy cwan | May 29th, 2017
A large worldwide study has found that, contrary to the popular thought, low-salt diets may not be beneficial and may actually increase the risk of cardiovascular disease (CVD) and death compared to average salt consumption. In summary, the study suggests that the only people who need to worry about reducing sodium in their diet are those with hypertension (high blood pressure) and have high salt consumption.
The study, led by investigators of the Population Health Research Institute (PHRI) of McMaster University and Hamilton Health Sciences, involved more than 130,000 people from 49 countries. They researchers looked specifically at whether the relationship between sodium (salt) intake and death, heart disease and stroke differs in people with high blood pressure compared to those with normal blood pressure.
The study showed that regardless of whether people have high blood pressure, low-sodium intake (i.e., less than three grams per day) is associated with more heart attacks, strokes, and deaths compared to average intake. In addition, the study shows that the risks associated with low-sodium intake are consistent regardless of a patient’s hypertension status. Further, the findings show that the harm associated with high sodium consumption (greater than 6 grams per day) appears to be confined to only those with hypertension.
Low sodium intake reduces blood pressure modestly, compared to average intake. However, the low sodium intake causes adverse elevations of several hormones, which may outweigh any blood pressure lowering benefits. This result is consistent with several previous studies showing that low-sodium, compared to average sodium intake, is related to increased cardiovascular risk and mortality, even though low sodium intake is associated with lower blood pressure.
Therefore, on the salt consumption, the key question that needs to be answered is not whether the blood pressure is lower with very low salt intake; rather it should be whether the very low salt intake improves health. The answer is no.
Thanks for reading.
Dr. Connie Wan
Journal Reference: Andrew Mente et al. Associations of urinary sodium excretion with cardiovascular events in individuals with and without hypertension: a pooled analysis of data from four studies. The Lancet, 2016 D
Source: Informed Nutrition