Dietary approach to stop hypertension (DASH) diet reduces blood pressure (BP) as effectively as one antihypertensive drug, yet its mechanism of action was never fully characterized.

We designed a translational inpatient trial to elucidate the biological pathway leading from nutritional change, through hormonal response, reversal of urine electrolytes ratio, to BP reduction.

A single-center open-label interventional trial. Volunteers were admitted for 14 days, transitioning from an American-style diet to DASH diet. Vital signs, blood, and urine samples were collected daily. Participants completed two 24-hour ambulatory BP measurements (ABPM) and two 24-hour urine collections on days 1 and 10. Nine volunteers completed the protocol. During inpatient stay, serum aldosterone increased from day 0 (mean 8.3 ± 5.0) to day 5 (mean 17.8 ± 5.8) after intervention and decreased on day 11 (mean 11.5 ± 4.7) despite continuous exposure to the same diet (p-value = 0.002). Urine electrolyte ratio ([Na]/[K]) decreased significantly from a mean of 3.5 to 1.16 on day 4 (p < 0.001). BP by 24-hour ABPM decreased by a mean of 3.7 mmHg systolic BP and 2.3 mmHg diastolic BP from day 1 to 10.

Shifting from a high-sodium/low-potassium diet to the opposite composition leads to aldosterone increase and paradoxical BP reduction. Urine electrolyte ratio reflects nutritional changes and should guide clinicians in assessing adherence to lifestyle modification.

‘DASH for Asthma’ (n 90) was a 6-month randomized controlled trial that demonstrated potential benefits of a DASH (Dietary Approaches to Stop Hypertension) behavioural intervention for improving diet quality and asthma control by comparing intervention to usual care in adults with uncontrolled asthma. The present study examined acceptability and feasibility of the intervention from the perspective of intervention participants and lifestyle coaches.

Grounded in Social Cognitive Theory, the 3-month intensive stage, including three individual and eight group sessions, focused on diet modifications and behavioural self-regulation. The 3-month maintenance stage contained telephone consultations. Participants and lifestyle coaches completed surveys including 5-point Likert scales and open-ended questions. We analysed data using descriptive and inductive content analyses.

Forty-six intervention participants (survey response rate was 65–72 %) and two lifestyle coaches.

Participants and lifestyle coaches were highly satisfied (all mean ratings >4) with individual and group sessions. Participants identified mastery of knowledge and skills (awareness, goal setting, self-monitoring, problem solving), social learning (class members sharing experiences and ideas) and good coaching skills (reflective listening, empathy, motivational counselling) as important contributors to self-efficacy and programme satisfaction. Participants also valued personalized feedback received in individual sessions. Lifestyle coaches viewed participant engagement as a facilitator to effective sessions. Finally, participants and lifestyle coaches identified food tasting as beneficial for observational learning and facilitation of participant engagement. High class attendance and self-monitoring rate also reflected the high engagement among participants.

The DASH behavioural intervention was feasible and highly acceptable to participants with uncontrolled asthma and lifestyle coaches.

Limited observational studies have considered habitual consumption of the general population to examine the relationship between the Dietary Approaches to Stop Hypertension (DASH) diet and obesity. The aim of the present study was to investigate adherence to the DASH diet in relation to general and central obesity among female nurses in Isfahan, Iran.

Cross-sectional study carried out among 293 female nurses aged >30 years who were selected by a multistage, cluster random sampling method. Usual dietary intakes were assessed using a validated FFQ. We constructed the DASH score based on foods and nutrients emphasized or minimized in the DASH diet, focusing on eight components: high intake of fruits, vegetables, nuts and legumes, low-fat dairy products and whole grains and low intakes of sodium, sweetened beverages, and red and processed meats. General and abdominal obesity were defined as BMI ≥25 kg/m2 and waist circumference ≥88 cm, respectively.

Isfahan, Iran.

Female nurses (n 293) aged >30 years.

Increased adherence to the DASH diet was associated with older age (P<0·01) and lower waist circumference (P=0·04). There was no statistically significant difference in the prevalence of general obesity between extreme quartiles of the DASH diet score. After adjustment for age, energy intake and other confounding factors, DASH diet score was not significantly associated with obesity. However, with further controlling for other dietary factors, those in the highest quartile of DASH diet score were 71 % less likely to have general obesity compared with those in the lowest quartile. In addition, following a DASH diet was inversely associated with central obesity after adjustment for potential confounders (OR=0·37; 95 % CI 0·14, 0·96).

We found that adherence to the DASH diet was inversely related to central obesity among Iranian adult females. This association remained significant even after adjustment for potential confounders.

The role of following the recommendations of Canada's Food Guide (CFG) and the Dietary Approaches to Stop Hypertension (DASH) diet on body composition in children is unknown. The present study assessed how conformity to the recommendations of these diets was associated with BMI, waist-to-height ratio (WHtR), waist-to-hip ratio (WHR), waist girth (WG), hip girth (HG) and risk of overweight in peri-adolescents.

CFG and DASH indices were derived from responses to a food questionnaire, with a higher index representing greater conformity to CFG and DASH diet recommendations. Body composition was assessed by trained research assistants.

Schools within the Niagara region (Ontario, Canada).

Children (n 1570) aged 12·4 (sd 0·3) years.

After adjustment for age to peak height velocity and total physical activity, a higher CFG index was associated with lower WHtR (b = −0·001, 95 % CI −0·002, −0·0004), WHR (b = −0·001, 95 % CI −0·002, −0·001) and WG (b = −0·18, 95 % CI −0·30, −0·07) in girls. No associations were observed in boys. In contrast, a higher DASH index was associated with decreased body composition measures in both genders. Specifically, the DASH index was negatively associated with BMI (girls: b = −0·07, 95 % CI −0·10, −0·04; boys: b = −0·05, 95 % CI −0·08, −0·02), WHtR (girls: b = −0·001, 95 % CI −0·002, −0·001; boys: b = −0·001, 95 % CI −0·002, −0·0004), WHR (girls: b = −0·001, 95 % CI −0·002, −0·001; boys: b = −0·001, 95 % CI −0·001, −0·00004), WG (girls: b = −0·24, 95 % CI −0·31, −0·16; boys: b = −0·15, 95 % CI −0·24, −0·07) and HG (girls: b = −0·15, 95 % CI −0·23, −0·07; boys: b = −0·12, 95 % CI −0·19, −0·04). A higher DASH index was also associated with lower odds of overweight in girls (OR = 0·70, 95 % CI 0·56, 0·87) and boys (OR = 0·76, 95 % CI 0·62, 0·93).

The DASH diet may prevent overweight in peri-adolescents.

With the upsurge in online dietary modification programmes, online dietary assessment tools are needed to capture food intake. Although the DASH (Dietary Approaches to Stop Hypertension) diet is recommended by the US Department of Agriculture, there are no online instruments that capture DASH food servings. Our objective was to assess the validity of a new, short, online dietary questionnaire developed to capture intake of DASH food servings. The DASH Online Questionnaire (OLQ) was validated against the well-known Block Food Frequency Questionnaire (FFQ).

This was a cross-sectional validation of the DASH OLQ, which contained eleven food groups (breakfast cereals; dairy; drinks; fats and oils; fruits; grains and snacks; meat, fish and poultry; mixed dishes; sweets; vegetables; and nuts, seeds and legumes). Each subject completed a DASH OLQ once weekly for four weeks and one 98.2 Block FFQ (110 questions) between weeks 2 and 4. DASH OLQ were averaged and then compared with the Block FFQ for nutrient intakes as well as intakes of DASH food groups.

Boston University Medical Center, Boston, Massachusetts.

One hundred and ninety-one faculty and staff at Boston University Medical Center aged 20–70 years.

There were significant positive correlations between the Block FFQ and the DASH OLQ for all food groups ranging from r = 0·8 for the nuts/seeds/legumes category to r = 0·3 for vegetables and mixed dishes. A comparison of nutrient intakes found strong positive correlations in all nutrient categories. Of particular interest in the DASH diet and the web-based nutrition and physical activity programme were total fat (r = 0·62), total carbohydrate (r = 0·67), total K (r = 0·68), total Ca (r = 0·69), total vitamin C (r = 0·60) and total energy intake (r = 0·68).

The DASH OLQ captures food and nutrient intake well in relation to the more established Block FFQ.