In a randomised controlled trial (RCT), healthy adults who consumed yellow pea-based pasta showed a significant reduction in oxidative stress and cardiovascular risk, according to a study led by researchers from Mizkan Holdings Central Research Institute.
“In conclusion, our results show that replacing a normal meal with yellow pea-based pasta once daily for four weeks significantly improved the oxidative stress marker levels.
“Together with our previous findings, this study provides evidence that pasta prepared from yellow peas is a promising functional staple food,” wrote researchers in Scientific Reports.
Pea (Pisum sativum L.) is one of the most widely produced legumes globally, with a 2021 production of 12 million tons, making it a key ingredient in food production.
Peas are attracting attention as a functional food since their nutritional components, such as proteins, minerals, and dietary fibre, are beneficial to human health.
Furthermore, due to the presence of polyphenols in pea hulls, especially flavonoids and phenolic acids, peas and pea-based products are known to have antioxidant and anti-inflammatory effects.
To tap on these health benefits, ZENB, a brand founded by Mizkan Holdings, developed a yellow pea-based pasta. The objective of this study was to investigate its functionality by simulating a real-life scenario that mimics typical daily eating habits.
The study, funded by Mizkan Holdings, involved researchers from Doshisha University and Ueno-Asagao Clinic, which specialises in clinical trials assessing functional food claims in Japan.
Replacing one meal a day with yellow pea-based pasta
The four-week study investigated the antioxidant effects of yellow pea-based pasta, as well as its impact on salt intake and postprandial blood glucose levels, by simulating typical daily eating habits. It is a follow-up to earlier findings, which showed that yellow pea pasta enhanced saltiness and suppressed postprandial blood glucose elevation.
For this open, parallel-group, randomised controlled trial, 40 healthy adult men and women aged 20–65 years were recruited. Their salt intake exceeded the recommended levels according to Japanese dietary standards.
They were randomly assigned to two groups – Twenty were allocated to the yellow-pea based pasta (YPP) group, while the other 20 were allocated to the control group.
The YPP group consumed one test meal per day, which was ZENB Noodles.
The control group maintained a normal diet.
Results and implications
Based on blood and urine samples, the YPP group showed significantly improved oxidative stress markers than the control group.
This was according to the BAP/d-ROMs ratios of both groups by the end of four weeks – where BAP stands for biological antioxidant potential, a measurement of antioxidant defences; and d-ROMs stands for diacron-reactive oxygen metabolites, an indicator of oxidative stress.
A higher BAP/d-ROMs ratio reflects a stronger antioxidant defence against oxidative stress, potentially lowering the risk of inflammation-related conditions such as cardiovascular disease.
The variation of BAP/d-ROMs ratios was significantly greater in the YPP group at 0.27 compared to the control group at − 0.11.
Researchers also measured lipid peroxide (LPO) levels, which shows when fats in cell membranes are damaged by oxidation. High LPO levels are associated with a higher risk of cardiovascular disease.
The control group showed a change of 0.11 in LPO levels, which was not statistically significant.
In contrast, the LPO level showed a significant decrease with a change of − 0.25 in the YPP group.
“The results of the BAP/d-ROMs ratio and LPO level measurement indicated that the YPP intake for four weeks improved the oxidative stress level in the participants,” researchers said.
However, the effects of yellow-pea based pasta on salt intake and blood glucose levels were limited.
By week four, daily urine salt was 9.63g/day for the control group and 8.75g/day for the YPP group – researchers did not find this statistically significant.
While both groups showed a reduction in salt intake, the difference between the two groups was not statistically significant, based on the brief-type self-administered diet history questionnaire (BDHQ) results.
As for Maximum Glucose (Max) level at day two, it was 175mg/dL for the control group and 156mg/dL for the YPP group.
Mean Amplitude of Glycemic Excursions (MAGE), which measures blood glucose variations, was 67.0mg/dL for the control group and 49.3mg/dL for the YPP group.
While the results showed significant differences in Max and MAGE on day two between the two groups, the YPP intake did not affect the other glycemic parameters. Moreover, YPP intake did not affect all glycemic parameters at other time points.
Since this trial aimed to replicate real-life conditions, the control group wasn’t necessarily consuming high-GI foods, as they were instructed to follow their normal diet. This could mean that their blood glucose responses weren’t as elevated as they might be in trials specifically designed to compare high- and low-GI diets, explained researchers.
This indicates that replacing a normal meal with a low GI food once a day does not necessarily result in a change in the blood glucose levels compared with those resulting from a normal diet without any intervention.
Additionally, the sensory test in this study showed that the participants’ sensitivity to saltiness did not change even after four weeks of YPP intake.
Individuals with a high salt intake level have a higher salt sensitivity threshold and are unable to feel satisfied unless they consume a larger amount of salt.
Therefore, to further reduce the salt intake level in real life, it is desirable to not only incorporate ingredients that enhance the salt sensitivity, such as YPP, into the diet, but also to use approaches that change both the salt sensitivity and palatability, said researchers.
“This study examined the antioxidant effect of YPP, as well as its effects on the salt intake and postprandial blood glucose levels, in a real-life setting. As a result, the effects on salt intake and blood glucose levels were limited.
“Furthermore, we observed a marked improvement in the levels of oxidative stress markers, which is likely attributed to the polyphenols and antioxidant components found in YPP, although it may also be associated with the slight improvement in the salt intake and postprandial blood glucose levels,” said researchers.
As inflammation is also associated with cardiovascular events, improvements in the biomarkers – BAP/d-ROMs ratio and LPO level – may contribute to reducing the risk of cardiovascular disease.
“As the number of people with cardiovascular disease continues to increase worldwide, YPP intake may help in [its] prevention and management…” researchers concluded.
Source: Scientific Reports
DOI: https://doi.org/10.1038/s41598-024-72290-6
“Yellow pea-based pasta’s impacts on the salt intake, glycemic parameters and oxidative stress in healthy individuals: a randomized clinical trial”
Authors: Mamoru Ito, Joto Yoshimoto et al.
