Fruit, vegetable diet a viable treatment for hypertension

A diet that is rich in fruits and vegetables can help treat individuals with primary hypertension by preventing chronic kidney disease (CKD) progression and reducing the risk of cardiovascular disease (CVD), suggest the results of a recent study.

“[D]ietary acid reduction with either fruits and vegetables or oral sodium bicarbonate (NaHCO3) yielded similar kidney protection, but fruits and vegetables yielded better improvement of CVD risk parameters,” the researchers said.

In this randomized controlled trial, 153 hypertensive macroalbuminuric patients on pharmacologic CKD and CVD protection were assigned to receive fruits and vegetables, oral NaHCO3, or usual care. The course of CKD progression and CVD risk indices were assessed over 5 years.

Participants who received fruits and vegetables or oral NaHCO3 showed slower CKD progression than those on usual care (mean –1.08 and –1.17 vs –1.94 mL/min/1.73m²/year, respectively; p<0.001). [Am J Med 2024;137:1114-1127.E8]

However, individuals on a fruit and vegetable diet had lower systolic blood pressure and greater improvement in CVD risk indices than those receiving NaHCO3 or usual care. Such benefits from fruits and vegetables were achieved despite lower doses of pharmacologic CKD and CVD protection.

“High fruit and vegetable diets are associated with reduced CKD and CVD but are infrequently used in hypertension treatment,” the researchers said. “Low acid diets are also associated with reduced CKD and CVD, and fruits and vegetables or oral NaHCO3 lowers dietary acid.”

First-line treatment

These findings support recommendations for diet as a first-line treatment of primary hypertension and CKD. In addition, dietary sodium appears to reduce the kidney and cardiovascular protective effects of antiangiotensin III therapy, a common treatment for albuminuric CKD. [Lancet 1988;332:530-533; Kidney Int 2024;105:S117-S314]

"These data support fruits and vegetables rather than NaHCO3 as the preferred dietary acid reduction strategy for patients with primary hypertension and CKD,” the researchers said.

In addition, diets high in fruits and vegetables must be considered as foundational, rather than adjunctive, in the management of primary hypertension, according to the researchers.

"These data suggest that a better approach is to begin patient management of primary hypertension with diets high in fruits and vegetables, with adjunctive pharmacologic kidney and cardiovascular protection as needed,” they said.

The current study was limited by the lack of specific information on compliance with the NaHCO3 prescription. However, participants in intervention groups had similar reductions in urine net acid excretion. This was consistent with increased alkali intake that was similar to the alkali intake provided by fruits and vegetables. [Kidney Int 2012;81:86-93]

"Future basic studies will decipher mechanisms by which the possibly vascular injury reflected by albuminuria mediates CKD and its progression as well as subsequent CVD,” the researchers said. “Future clinical studies will determine if patients with levels of albuminuria less than macroalbuminuria are similarly responsive to dietary acid reduction.”