Fruits, Veggies Lower Blood Pressure 17% and Risk for Stroke by 15%

An apple a day may not be enough to keep the doctor away but, according to a new study, five apples just might.

Healthy adults who consumed at least five servings of fruit and vegetables daily--the amount recommended in the US and UK--had lower blood pressure than adults who consumed fewer servings over 6 months.

On a population level, the reduction in blood pressure observed in the study would translate into a 17% reduction in the rate of high blood pressure, a 6% lower risk of coronary heart disease and 15% fewer strokes, the researchers estimate.

The findings support previous research showing that a fruit- and vegetable-rich diet boosts levels of disease-fighting antioxidants in the blood and reduces blood pressure in the short term.

To investigate the longer-term effects of such a diet, the researchers from the University of Oxford in the UK assigned nearly 700 adults aged 25 to 64 to follow their regular diet or to eat at least five servings of fruit and vegetables daily. One serving is equal to 80 grams--about one medium-sized piece of fruit or half a cup of cooked vegetables. Adults who took vitamin pills were not included in the study.

Over the next 6 months, levels of certain antioxidants--including vitamin C, lutein and beta-carotene--increased in the group of adults encouraged to boost their fruit and vegetable intake but not in the other group. There were no changes in body weight or cholesterol levels but the systolic blood pressure of adults who consumed more fruit and vegetables fell by about 4 mm Hg and their diastolic pressure fell by 1.5 mm Hg.

The systolic blood pressure is the first number in a blood pressure reading, and the diastolic blood pressure is the second.

The fall in blood pressure achieved in our study is unlikely to be attributable to reduced fat intake or changes in physical activity," Dr. Andrew Neil and colleagues report.

They suggest that a higher intake of potassium, which is abundant in many fruits and vegetables and is associated with lower blood pressure, may underlie the health benefits. Lower levels of sodium may also contribute to the benefits, although the researchers did not measure blood sodium.

About half of adults in the UK currently consume at least five servings of fruit and vegetables daily, according to the study in the May 28th online issue of The Lancet.

"The effects of the intervention on fruit and vegetable consumption, plasma antioxidants, and blood pressure would be expected to reduce cardiovascular disease in the general population," the study authors conclude.