A diet rich in vegetables has been associated with lower risk of various health disorders including heart disease and yet the authors of the paper said vegetable consumption in the US has fallen over the past decade.
Working from the nutritional science lab at the University of California, Davis, the scientists therefore sought to determine whether drinking vegetable juice is a practical way of closing the gap between dietary recommendations and vegetable intake. The second research aim was to see how vegetable juice affected cardiovascular health.
To fulfill these objectives, a randomised, controlled study was constructed with 90 volunteers who received 0, 8 or 16 fluid ounces of vegetable juice daily for 12 weeks and were asked to follow the Dietary Approaches to Stop Hypertension (DASH) diet.
Daily vegetable servings with and without the vegetable juice were measured along with heart health parameters including blood pressure.
Study results
Without the addition of the juice, the results showed that consumption of vegetable juice was below both dietary guidelines and DASH diet recommendations. This was in spite of the education that the participants received about the DASH diet.
Compared to public health recommendations of 4 servings per day, average vegetable intake for all groups, without counting vegetable juice, was 2.6 servings per day after 6 weeks and 2.3 servings per day after 12 weeks.
But once the vegetable juice was counted, the participants were able to reach the daily recommendations.
The authors concluded from these results that vegetable intake, even in an educated, healthy population, remains lower than recommendations and that adding vegetable juice daily was “an effective and acceptable way for healthy adults to close the dietary vegetable gap.”
Heart health impact
Regarding the secondary aim of the study, the authors said that generally parameters associated with heart health did not change over time. However, participants who were pre-hypertensive at the start of the study showed a significant decrease in blood pressure during the intervention period.
The authors called for more research to be done to explore the health impact of drinking vegetable juice among other at risk subgroups.
Funding for the study was provided by the Campbell Soup Company, which makes V8 vegetable juice, and the UC Davis Center for Health and Nutrition Research.
Source: Nutrition Journal
The use of a commercial vegetable juice as a practical means to increase vegetable intake: a randomized controlled trial
Authors: Sonia F Shenoy, Alexandra G Kazaks, Roberta R Holt, Hsin Ju Chen1, Barbara L Winters, Chor San Khoo, Walker SC Poston, C Keith Haddock, Rebecca S Reeves, John P Foreyt, M Eric Gershwin and Carl L Keen