The use of a commercial vegetable juice as a practical means to increase vegetable intake: a randomized controlled trial.
BACKGROUND
Recommendations for daily dietary vegetable intake were increased in the 2005 USDA Dietary Guidelines as consumption of a diet rich in vegetables has been associated with lower risk of certain chronic health disorders including cardiovascular disease. However, vegetable consumption in the United States has declined over the past decade; consequently, the gap between dietary recommendations and vegetable intake is widening. The primary aim of this study is to determine if drinking vegetable juice is a practical way to help meet daily dietary recommendations for vegetable intake consistent with the 2005 Dietary Guidelines and the Dietary Approaches to Stop Hypertension (DASH) diet. The secondary aim is to assess the effect of a vegetable juice on measures of cardiovascular health.


METHODS
We conducted a 12-week, randomized, controlled, parallel-arm study consisting of 3 groups of free-living, healthy volunteers who participated in study visits at the Ragle Human Nutrition Research Center at the University of California, Davis. All subjects received education on the DASH diet and 0, 8 or 16 fluid ounces of vegetable juice daily. Assessments were completed of daily vegetable servings before and after incorporation of vegetable juice and cardiovascular health parameters including blood pressure.


RESULTS
Without the juice, vegetable intake in all groups was lower than the 2005 Dietary Guidelines and DASH diet recommendations. The consumption of the vegetable juice helped participants reach recommended intake. In general, parameters associated with cardiovascular health did not change over time. However, in the vegetable juice intervention groups, subjects who were pre-hypertensive at the start of the study showed a significant decrease in blood pressure during the 12-week intervention period.


CONCLUSIONS
Including 1-2 cups of vegetable juice daily was an effective and acceptable way for healthy adults to close the dietary vegetable gap. Increase in daily vegetable intake was associated with a reduction in blood pressure in subjects who were pre-hypertensive at the start of the trial.


BACKGROUND
Clinicaltrials.gov NCT01161706.
Shenoy
Sonia F
SF
Department of Nutrition, University of California Davis, Davis, California 95616, USA.
Kazaks
Alexandra G
AG
Holt
Roberta R
RR
Chen
Hsin Ju
HJ
Winters
Barbara L
BL
Khoo
Chor San
CS
Poston
Walker S C
WS
Haddock
C Keith
CK
Reeves
Rebecca S
RS
Foreyt
John P
JP
Gershwin
M Eric
ME
Keen
Carl L
CL
D000328:Adult; D001628:Beverages; D004032:Diet; D005260:Female; D006801:Humans; D006973:Hypertension / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D014675:Vegetables