'Low-salt' Bread as a Means of Reducing Dietary Salt and Lowering Blood Pressure
'Low-salt' Bread as a Means of Reducing Dietary Salt and Lowering Blood Pressure
In the context of public health, reformulation of bread in terms of salt content remains an
 important measure to help achieve a reduction in salt intake in the population. Therefore,
 the aim of this study was to examine, using a 5-week cross-over design, food-based
 intervention trial, the potential for inclusion of 'low-salt' bread as part of a pragmatic
 reduced-salt diet on blood pressure (BP) in adults with slightly to moderately elevated BP.

 The study consisted of a randomized crossover trial of the effect of reduced-salt intake or
 usual-salt intake for 5 weeks on BP (as the primary outcome) in adults with slightly to
 moderately elevated BP (seated office systolic BP >120 and <160 mmHg or a diastolic BP >80
 and <95 mmHg; identified by a pre-screening phase).

 Subjects were randomly assigned to the reduced-salt diet or their usual-salt diet (control)
 for 5 weeks, followed by crossover to the alternative dietary regimen for a further 5 weeks.
 Subjects randomized to start on the reduced-salt diet were asked to restrict their
 consumption of dietary salt using a combination of pragmatic dietary advice as well as the
 replacement of bread and a limited number of other foods with equivalent foods which had
 lower salt content; these were provided to the participants. At the beginning of the salt
 restriction period, a research nutritionist provided the subjects with a list of the common
 salt-containing food and were asked to limit the consumption of such, as feasible. The
 subjects received in-house prepared 'low-salt (<0.3 g/100 g)' brown or white sliced pan bread
 as well as no-salt margarine/butter, and were given luncheon meats with no added salt, if
 desired (optional); these were supplied regularly by the research staff. Subjects commencing
 the trial on the control diet were allowed to follow their usual diet but were asked to
 consume an in-house produced brown or white sliced pan bread equivalent in composition to the
 low-salt version but with its more typical salt content (1.2 g/100 g).

 Participants met the research staff weekly to receive breads and no-salt margarine/butter as
 well as luncheon meats (where applicable), and at these meetings the staff promoted
 compliance with the intervention and encouraged completion of the study protocol.

 BP and other assessments were made at baseline and at the end of week 5 and week 10.
Brief background and context for the study:

 The World Health Organization's Global Action Plan for the Prevention and Control of
 Non-Communicable Disease includes a voluntary global target of a 30% relative reduction in
 mean population intake of salt/sodium by 2025. Bread and cured/processed meats collectively
 contribute anything from about a third upwards of total salt intake of adults in many Western
 countries. Reformulation of bread in terms of salt content remains an important measure to
 help achieve a reduction in salt intake in the population. Therefore, the aim of this study
 was to examine, using a 5-week cross-over design, food-based intervention trial, the
 potential for inclusion of 'low-salt' bread as part of a pragmatic reduced-salt diet on blood
 pressure (BP) in adults with slightly to moderately elevated BP.

 Design:

 The study consisted of a randomized crossover trial of the effect of reduced-salt intake or
 usual-salt intake for 5 weeks on BP (primary outcome) and biochemical markers of calcium and
 bone metabolism as well as plasma lipids (secondary outcomes) in adults with slightly to
 moderately elevated BP.

 Potential volunteers were screened for BP over 3 weeks preceding the intervention phase of
 the trial during which seated office systolic and diastolic BP were measured weekly and those
 with systolic BP >120 and <160 mmHg or a diastolic BP >80 and <95 mmHg were considered
 eligible.

 The dietary intervention phase of the trial was designed in two successive dietary periods,
 each of 5 weeks. Subjects were randomly assigned to the reduced-salt diet or their usual-salt
 diet (control) for 5 weeks, followed by crossover to the alternative dietary regimen for a
 further 5 weeks. At baseline (week 0), the subjects visited the Human Nutrition Studies Unit
 within University College Cork in a fasting state and had their BP measured. Prior to the
 baseline visit, subjects received instructions on how to collect a 24-h urine sample and were
 provided with a suitable container for collection. On the day of the baseline visit, subjects
 brought the 24-h urine sample collected from the previous day and deposited it in a cold room
 area dedicated for such collections. A blood sample was taken from each subject between 08.30
 am and 10.30 am by a trained phlebotomist and anthropometric measures including height and
 weight, were taken. A health and lifestyle questionnaire, which assessed physical activity,
 general health, smoking status and alcohol consumption was completed by each subject.
 Subjects randomized to start on the reduced-salt diet were asked to restrict their
 consumption of dietary salt using a combination of pragmatic dietary advice as well as the
 replacement of bread and a limited number of other foods with equivalent foods which had
 lower salt content; these were provided to the participants. At the beginning of the salt
 restriction period, a research nutritionist provided the subjects with a list of the common
 salt-containing food and were asked to limit the consumption of such, as feasible. The
 subjects received in-house prepared 'low-salt (<0.3 g/100 g)' brown or white sliced pan bread
 as well as no-salt margarine/butter, and were given luncheon meats with no added salt, if
 desired (optional). Subjects commencing the trial on the control diet were allowed to follow
 their usual diet but were asked to consume an in-house produced brown or white sliced pan
 bread equivalent in composition to the low-salt version but with its more typical salt
 content (1.2 g/100 g).

 During the intervention phase, each participant made 2 further visits to the study unit, one
 each on the last day of dietary period 1 (week 5) and dietary period 2 (week 10). At these
 visits, BP measurements were taken as well as other anthropometric measures, including height
 and weight. An overnight fasting blood sample was also taken from each participant between
 08.30 am and 10.30 am by a trained phlebotomist, and on each of the visits, the subjects
 provided a 24-hour urine sample collected the previous day. Following blood sampling the
 participants received their breakfast.

 Participants met the research staff weekly to receive breads and no-salt margarine/butter as
 well as luncheon meats (where applicable), and at these meetings the staff promoted
 compliance with the intervention and encouraged completion of the study protocol.
Inclusion Criteria:

 -  consenting adult Caucasian men and women, aged ≤65 y;

 -  a seated office systolic BP >120 and <160 mmHg and/or a diastolic BP >80 and <95 mmHg
 (based on the mean BP across 3 screening visits as part of a pre-intervention phase of
 the trial)

 -  willing to consume study breads

 Exclusion Criteria:

 -  taking anti-hypertensive medication;

 -  taking any medications known to interfere with blood pressure or calcium or bone
 metabolism;

 -  Severe medical illness;

 -  celiac disease;

 -  hypercalcemia;

 -  known intestinal malabsorption syndrome,

 -  excessive alcohol use (>14 drinks/week);

 -  pregnancy