Tailored Messaging to Reduce Sodium Intake

People with high blood pressure often get advice to lower their salt or sodium intake. High
dietary sodium intake is linked to high blood pressure, stroke, heart failure and kidney
disease. U.S. federal guidelines advocate daily sodium intake of less than 2,300 milligrams
(mg). The estimated average sodium intake for Americans is 3,400 mg per day. In recent years,
consumption of processed and restaurant foods has substantially increased. More than 75% of
sodium in the average U.S. diet now comes from these sources.

The mobile application will deliver tailored messages based on the user's location and
previously identified high-sodium food items that they commonly consume.

This 8-week research study at Visit 1 or baseline will consent and randomize 50 eligible
adults with high blood pressure to use the mobile application daily or to follow their usual
eating pattern with no access to the application.

All participants will be asked to complete four surveys at baseline and Week 8: Block Food
Frequency Questionnaire, Block Sodium Screener, Self-care Confidence in following a Low
Sodium Diet and the Automated Self-administered 24-Hour Dietary Recall survey. All
participants will be asked to provide a baseline and end of study 24-hour urine collection,
regularly provide home blood pressure measurements and urine dipstick tests every two weeks.

Inclusion Criteria:

- > 18 years of age

- Hypertension

- Use of anti-hypertensive therapy for at least 3 months, with stable anti-hypertensive
therapy (medication type and dose) for at least 2 weeks

- Daily sodium intake of >2,000 mg with sodium to kcal ratio > 1, estimated via Food
Frequency Questionnaire

- Ownership and use of an Apple iPhone

Exclusion Criteria:

- Chronic Kidney Disease

- Heart Failure

- Systolic Blood Pressure >180 mm Hg

- Diastolic Blood Pressure >110 mm Hg

- Use of a loop diuretic or corticosteroid

- Insulin dependent diabetes mellitus