Avocado & Mango Improve Endothelial Function in Prediabetes | Cardiology Today

Daily consumption of avocado and mango appears to offer a modest but measurable benefit to vascular health in individuals with prediabetes, according to research published this week in the Journal of the American Heart Association. The study, led by researchers at the Illinois Institute of Technology, found that incorporating one avocado and one cup of mango into a daily diet improved endothelial function – the ability of blood vessels to dilate – compared to a control diet. Whereas the effect was relatively small, approximately a 1% increase in flow-mediated vasodilation, researchers say it highlights the potential of simple dietary adjustments to positively influence cardiometabolic risk.

Endothelial Function and Prediabetes: Why This Matters

Endothelial dysfunction is an early marker of cardiovascular disease and is often present in individuals with prediabetes, a condition characterized by elevated blood sugar levels that haven’t yet reached the threshold for a type 2 diabetes diagnosis. The endothelium, the inner lining of blood vessels, plays a crucial role in regulating blood flow, blood clotting, and inflammation. When it doesn’t function properly, it can contribute to the development of atherosclerosis – the buildup of plaque in the arteries – and increase the risk of heart attack and stroke. The study aimed to determine if adding specific whole foods, known for their beneficial nutrient profiles, could improve this key indicator of vascular health.

Study Design and Key Findings

The randomized, controlled trial involved 82 participants with prediabetes. Participants were assigned to either a dietary intervention group, consuming one avocado and one cup of mango daily as part of a 1,500-1,750 calorie diet, or a control group, which received an energy- and macronutrient-matched diet without the avocado and mango. The study duration was eight weeks. The primary outcome measured was change in flow-mediated vasodilation (FMD), a non-invasive measure of endothelial function. Secondary outcomes included changes in blood pressure, pulse-wave velocity, and various metabolic markers.

Researchers observed a statistically significant increase in FMD in the avocado-mango group compared to the control group (P = .008). Specifically, the avocado-mango group experienced approximately a 1% improvement in FMD from baseline, while the control group showed a decrease. Men in the avocado-mango group experienced modest reductions in both central and brachial diastolic blood pressure, though these effects were not observed in women. The study also noted increases in total fruit intake, dietary fiber, vitamin C, and monounsaturated fat intake among those consuming avocado and mango (P for all &lt. .05).

What Explains the Benefits? Potential Mechanisms

While the study demonstrates an association between avocado and mango consumption and improved vascular health, it doesn’t definitively prove causation. Researchers speculate that several factors may contribute to the observed benefits. Britt Burton-Freeman, PhD, professor of food science and nutrition at Illinois Institute of Technology, suggests that altered cellular redox balance and increased nitric oxide (NO) bioavailability could play a role. NO is a molecule that helps relax blood vessels, improving blood flow. Avocados and mangoes are rich in antioxidants and other bioactive compounds that may enhance NO production or protect it from degradation.

Another potential mechanism involves the gut microbiome. Both avocados and mangoes contain fiber, which feeds beneficial gut bacteria. These bacteria produce metabolites that can have positive effects on cardiovascular health. Further research is needed to fully elucidate the underlying mechanisms.

Limitations and Considerations

It’s crucial to acknowledge the study’s limitations. The sample size of 82 participants is relatively small, which limits the generalizability of the findings. The study duration of eight weeks is also relatively short, and it’s unclear whether the observed benefits would be sustained over a longer period. The study also relied on self-reported dietary intake, which is subject to recall bias. Finally, the observed effects on diastolic blood pressure were only significant in men, suggesting that sex-specific factors may influence the response to this dietary intervention.

Contextualizing the Findings: Risk and Relative Benefit

A 1% improvement in flow-mediated vasodilation, while statistically significant, may seem modest. However, experts emphasize that even small improvements in vascular function can have cumulative benefits over time. It’s crucial to remember that this study examined a specific dietary intervention in individuals with prediabetes. The findings may not be directly applicable to individuals with established cardiovascular disease or those without prediabetes. The study does not suggest that avocado and mango are a “cure” for prediabetes or cardiovascular disease, but rather that they can be a valuable component of a heart-healthy diet.

What’s Next: Ongoing Research and Guidance Updates

Researchers are continuing to investigate the effects of specific dietary components on cardiovascular health. Future studies will likely explore the optimal dose and duration of avocado and mango consumption, as well as the underlying mechanisms responsible for the observed benefits. The Hass Avocado Board and National Mango Board funded this study, and further research is anticipated. Current dietary guidelines from organizations like the American Heart Association emphasize the importance of a diet rich in fruits, vegetables, and whole grains for cardiovascular health. Public health authorities continue to monitor emerging research and will update guidance as new evidence becomes available. Individuals with prediabetes or concerns about their cardiovascular health should consult with a qualified healthcare professional for personalized advice.

Ongoing surveillance of cardiometabolic risk factors and dietary patterns will be essential to refine public health recommendations and identify effective strategies for preventing cardiovascular disease.