Blood Plasma Metabolites Provide New Tools for Diet Assessment

Recent research has highlighted the potential of blood metabolites—molecules generated during metabolic processes like amino acids and peptides—as objective biomarkers to assess dietary intake. Traditionally, dietitians and healthcare professionals rely on self-reported dietary records, such as questionnaires and food diaries, which can be prone to inaccuracies and misreporting. To overcome these limitations, scientists have focused on analyzing metabolites in blood plasma to gain more precise insights into individuals' eating habits.

A study conducted by researchers at New York University examined plasma samples from participants involved in two controlled trials aimed at monitoring adherence to the portfolio diet, which is designed to reduce cholesterol levels through plant-based foods like soy, nuts, plant sterols, and viscous fibers. Participants in these trials received all dietary foods during weekly clinic visits over four weeks, with plasma samples collected at baseline, week two, and week four. The first trial included 34 individuals divided into three groups: a portfolio diet group, a control diet group, and a control diet with cholesterol-lowering medication. The second trial involved 25 participants split into two groups: the portfolio diet group and a control group.

The analysis revealed significant changes in the levels of specific metabolites. Out of 496 known metabolites, 145 (about 29%) varied notably in the first trial's portfolio diet group, while 63 (around 12%) changed significantly in the second trial. When examining both trials together, 52 metabolites (roughly 10%) showed consistent alterations, including increases in metabolites linked to plant-based diets like N2-acetylornithine and lenticin, as well as decreases in lipids associated with saturated fats.

These findings suggest that certain metabolites could serve as biomarkers to monitor adherence to dietary patterns such as the portfolio diet. "While promising, further research is necessary to validate these metabolites as reliable objective indicators of dietary intake," said Andrea J. Glenn, the study's lead author. Ultimately, utilizing metabolite profiling in blood could enhance the accuracy of dietary assessments, leading to better dietary interventions and health outcomes.

Source: https://medicalxpress.com/news/2025-04-metabolites-blood-plasma-insights-diet.html