Conducted in collaboration with the researchers of the Food and Nutrition Institute of Federal University of Rio de Janeiro, Brazil, the study involved the supplementation of the ingredient in a healthy population aged 60 or older (n=12) over 12 weeks.
The resulting data revealed a notable increase in plasma nitrate levels and trend of improvement in insulin sensitivity in the group receiving beetroot extract.
“This preliminary study was conducted to underscore the safety and tolerability of Sabeet, but we are pleased to see the benefits it indicated as well,” said Shaheen Majeed, Global CEO & Managing Director of The Sami-Sabinsa Group. “These findings align with our commitment to providing scientifically backed, safe and effective dietary supplements. Sabinsa extends its gratitude to the team in Food and Nutrition Institute at Federal University of Rio de Janeiro for their collaboration in this study, and we look forward to continuing collaboration.”
Beetroot safety
In recent years, there has been a notable surge in the popularity of beetroot-based dietary supplements, driven by their rich nitrate composition, according to the report. “Several types of beetroot-based dietary supplements can be found in markets worldwide; however, ensuring the safety of dietary supplements is a crucial consideration, as there is limited evidence on their safety, especially for older populations,” it noted.
Given the possibility that roots, such as beetroot, accumulate heavy metals, such as cadmium (Cd), mercury (Hg) and lead (Pb), prolonged exposure to these may cause some health complications, the authors noted, hence the need for the new safety study.
Study details
The researchers conducted a randomized, double-blind, placebo-controlled, parallel study in which participants were randomized to beetroot supplement treatment (BET) or placebo (PLA).
They were instructed to ingest 10 g of the supplement diluted in 250 mL of water, respectively, twice a day for 12 weeks.
Anthropometric evaluation was conducted, and blood samples and hemodynamic measurements were taken at weeks four, eight and 12. These assessments were carried out at least 12 hours after ingestion of the second supplement package to avoid acute effects of the supplements.
Participants were instructed to maintain their daily routine throughout the study and to fast for at least 12 hours and refrain from physical exercise for 24 hours before each test visit.
A significant interaction effect was observed for insulin levels, with the BET group showing lower levels between weeks four and 12. However, the insulin AUC from week 0 to week 12 was not different statistically between the groups.
The homeostasis model assessment of insulin resistance (HOMA-IR) index was also reduced only in the BET group between weeks four and 12, and the homeostasis model assessment of beta-cell function (HOMA-β) index showed a significant difference between weeks 0 and 12.
The nitrate AUC significantly increased in the BET group compared to the PLA group. However, there were no significant changes in the nitrite AUC between the groups even though there was a very large effect size.
The authors noted the small number of participants resulted in a limited statistical power to demonstrate the specific benefits of the beetroot extract on health-related parameters.
Mechanisms of action
In line with a previous study by Wootton-Beard et al. (2014), a decrease in fasting insulin levels was observed between the start and the end of the present study only in the BET group. Wootton-Beard et al. suggested that the polyphenols (e.g., betalains) and nitrate found in the beetroot may have contributed to the decrease in insulin concentration.
In addition to the properties of beetroot that are beneficial for glycemic control, two studies have highlighted its effect on lipid profile variables (i.e., TC, LDL-c, HDL-c and TG), demonstrating reduced concentrations of TC, LDL-c and TG after a single dose and six weeks of beetroot juice supplementation.
The mechanism by which beetroot can lead to changes in lipid metabolism is not entirely understood. However, corroborating the findings of the present study, a recent systematic review with a meta-analysis has demonstrated that beetroot consumption had no significant effect on any lipid profile variables, concluding that beetroot consumption cannot be categorized as an effective nutrition strategy for the adjustment of one’s lipid profile.
Given the limited number of male participants (n=3), the researchers suggested the need for a further analysis to determine sex differences in the investigated variables after beetroot extract supplementation was not possible.
They noted: “It was necessary to conduct this study before investigating the efficacy of this dietary supplement in a larger sample of older people to detect changes in other health parameters, such as vascular function and muscle quality, and to promote the overall safety and efficacy of beetroot-based dietary supplements”.
Source: Nutrients
doi: 10.3390/nu16121942
“Evaluation of 12-Week Standardized Beetroot Extract Supplementation in Older Participants: A Preliminary Study of Human Health Safety”
Authors: Vivian Dos Santos Pinheiro, et al.