A review of dietary interventions aimed at controlling hypertension.

Before planning programs to change dietary behavior in groups of individuals, evidence about the effectiveness of different interventions is needed. Articles published in the journals indexed by Index Medicus between the years 1975-84 were reviewed for evidence concerning the effectiveness of dietary modification programs in achieving dietary change. All program evaluations published in English and aimed at control of blood pressure levels in adults were eligible for review. Twenty-nine articles relevant to the synthesis contained sufficient information evaluating the contribution of dietary intervention. These 20 studies addressed changes in fat consumption, reduction in salt intake and reduction in calories consumed. The methods of intervention ranged from residential programs, through individual counseling and group discussion involving spouses, to audiovisual tapes. The studies had varying periods of follow-up; among those with one or more years of follow-up, a number of studies were able to demonstrate effectiveness using different outcome measures. For some dietary components, notably changes in fat intake and reduction in salt consumption, it has been possible to identify a minimal effective intervention, such as self-help materials or individual instruction, while changes in calorie intake or weight seem to require group counseling with family member involvement. The findings from this information synthesis should prove useful to those planning dietary interventions.