December 10, 2014

comparing sugar with salt as causes of hypertension and CVD

Researchers publishing in the journal Open Heart have suggested that it might be sugar rather than salt which has greater effects on hypertension and cardiovascular disease. This analysis was accompanied by a roundup.

Title, Date of Publication & Journal

The wrong white crystals: not salt but sugar as aetiological in hypertension and cardiometabolic disease.

10 December 2014, Open Heart

Study’s main claims – and are they supported by the data

This study provides no new evidence on the impact of either sugar or salt intake on blood pressure. It is a review of selected existing evidence.

One of the main claims they make is supported by the evidence they reviewed:  that higher sugar intake increases blood pressure.

Some of the claims appear to be based on no evidence at all: reducing the amount of sugar in processed foods may lead to an increase in their consumption causing a greater prevalence of cardiometabolic disease. To support this claim the authors refer to a letter they wrote to a journal, not a scientific study providing evidence to this effect.

Strengths/Limitations

• The authors have conducted a review of existing evidence but have not carried out a systematic review. They appear to have selected publications that support their hypotheses but ignored publications that do not.

• The only figures they quote from meta-analyses are the average reductions in blood pressure resulting from reducing (1) salt intake and (2) sugar intake. However, for the former they do not quote a more recent meta-analysis published in 2013 which showed greater average reductions in blood pressure after reducing salt intake (compared to the study they did quote).

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