High dietary acid load may increase risk of total, cause-specific mortality
A high dietary acid load score appears to elevate the risk of total mortality and mortality from cardiovascular disease (CVD), particularly ischaemic heart disease (IHD), according to a recent study involving Japanese adults.
To investigate the association between dietary acid load and total and cause-specific mortality, researchers conducted a large-scale, population-based, prospective cohort study in Japan involving 42,736 men and 49,742 women (aged 45 to 75 years) who had no history of cancer, stroke, IHD or chronic liver disease at baseline.
A validated 147-item food-frequency questionnaire was used to evaluate dietary intake, while nutrient intake was utilized to derive potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores. Death and cause of death were identified by using the residential registry and death certificates.
Researchers used Cox proportional hazards regression to estimate hazard ratios (HRs) and 95 percent confidence intervals (Cis) for total and cause-specific mortality with adjustment for potential confounding variables.
A total of 12,993 deaths occurred during a median 16.9 years of follow-up. There was an association between a higher PRAL and higher total mortality (multivariable-adjusted HR for mortality for the highest vs the lowest quartiles of PRAL scores, 1.13; 95 percent CI, 1.07 to 1.18; p<0.001 for trend).
An association existed between such a score and mortality from CVD (HR, 1.16; 1.06 to 1.28) and particularly from IHD (HR, 1.16; 1.02 to 1.33). There were similar associations between NEAP score and total and cause-specific mortality.
Finally, PRAL score was not associated with cancer mortality.
“Diet-induced metabolic acidosis has been linked to cardiometabolic abnormalities including hypertension and type 2 diabetes,” researchers said.