Study · Nutrients · 2023Conflicts declared

Smartphone app for measuring sodium intake in people

What it found

In 46 people, sodium intake logged in a smartphone app was lower than sodium estimated from 24-hour urine, but the two measures moved together.

The study ran for six months.

What they found

Studies in people

App vs urine sodium

At the start, the app gave an average of 2020.9 mg of sodium per day, while 24-hour urine gave 2857.6 mg per day. At six months, the app gave 1456.0 mg per day and urine gave 2698.3 mg per day.

Correlation between methods

Sodium intake from the app was positively linked to sodium from 24-hour urine at the start and at six months. The link was moderate.

Meal logging

Participants logged their meals about 16.2 times per week on average.

Urine sodium levels

The average 24-hour urine sodium was 124.3 mmol per day at the start and 117.4 mmol per day at six months.

Agreement across ranges

The difference between app and urine sodium was fairly consistent across the range of intakes, but the app tended to give lower values.

What the authors conclude

“In conclusion, dietary sodium intake measured using a smartphone application correlated well with that estimated using 24-h urine sodium level.”
Jung CY, Kim Y, Kim HW, et al, 2023

Also in their conclusions

  • They conclude that dietary sodium intake measured using a smartphone application correlated well with that estimated using 24-h urine sodium level.
  • They state that further studies are warranted for its generalized application.

How it was done

Accurate estimation of sodium intake is needed to test salt-reduction strategies, but no standard method exists and usual diet questionnaires can be inaccurate.

They followed 46 adults at a Korean hospital for six months. All had high blood pressure and used a smartphone food-logging app; sodium from the app was compared with sodium estimated from 24-hour urine collections.

What it can’t tell you

  • The study was done in Korean adults with high blood pressure, so the results may not apply to other groups.
  • Only one 24-hour urine collection was done at each visit, so day-to-day changes in sodium intake could affect the results.
  • The app's sodium estimates may differ from actual intake because food labels can be off by up to 25%.

The paper

Title
Effectiveness of a Smartphone Application for Dietary Sodium Intake Measurement
Type
Study
Evidence
Studies in people
Summarised from
Full text
Cite
Jung CY, Kim Y, Kim HW, et al (2023). Effectiveness of a Smartphone Application for Dietary Sodium Intake Measurement. Nutrients. doi:10.3390/nu15163590Free full textPubMed 37630780DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error