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In A Nutshell
- In a 24-week trial, adults with prediabetes who ate a daily mango had lower fasting blood sugar compared to those eating a calorie-matched granola bar.
- Despite nearly three times more natural sugar, mango eaters kept their HbA1c stable, while the granola bar group’s levels rose.
- The mango group gained lean body mass and trended toward lower body fat, while the control group showed increases in BMI and waist-to-hip ratio.
- Findings suggest whole-fruit sugars, packaged with fiber and nutrients, act differently than added sugars in processed snacks.
TALLAHASSEE, Fla. — A daily mango habit produced unexpected results for people with prediabetes: even though the tropical fruit contained more natural sugar than a granola bar, it actually lowered blood sugar levels while increasing lean body mass over six months.
The counterintuitive findings from a study conducted at Florida State University and led by George Mason University researcher Raedeh Basiri challenge the conventional wisdom that people at risk for diabetes should avoid sweet fruits. It’s worth noting that the study was funded by The National Mango Board; however, the agency had no role in the design of the study, nor in the collection, analysis, or interpretation of data.
Published in the journal Foods, the research followed 23 adults with prediabetes who ate either 300 grams of fresh mango or a calorie-matched granola bar daily for 24 weeks.
By the study’s end, the mango group had significantly lower fasting blood glucose compared to granola bar eaters. Even though mangos contained about 32 grams of natural fruit sugars daily versus just 11 grams of added sugars in the processed bars, the mango eaters saw their long-term blood sugar marker (HbA1c) remain stable. The granola bar group’s HbA1c levels increased significantly over the same period.
Sweet Fruit, Leaner Bodies
Interestingly, not only did the mango group avoid blood sugar deterioration, they also increased fat-free mass while losing body fat. Participants experienced a borderline significant decrease in body fat percentage and a notable increase in fat-free mass, which includes muscle, bone, and organ tissue. The control group showed numerical increases in body mass index and waist-to-hip ratio, though not all changes reached statistical significance.
These body composition changes could matter for long-term diabetes risk. Research consistently shows that greater fat-free mass protects against Type 2 diabetes by improving insulin sensitivity and glucose metabolism. People with higher relative muscle mass have lower insulin resistance and reduced prediabetes risk across large population studies.
Meanwhile, the trend toward expanding waistlines in the granola bar group mirrors the trajectory that typically leads from prediabetes to full-blown type 2 diabetes.
Fruit Matrix Beats Sugar Math
The study aimed to evaluate how daily mango consumption affects blood sugar control and body composition in people with prediabetes. Researchers chose a calorie-matched granola bar as the control to isolate what they call the “whole-fruit matrix effect.” This is the idea that fiber, vitamins, and bioactive compounds in intact fruit matter more than sugar content alone.
“Despite containing more intrinsic sugars than the isocaloric granola-bar comparator, mango produced more favorable glycemic indices and body composition changes,” the researchers wrote in their paper.
The mango group also showed improved insulin sensitivity and reduced insulin resistance compared to controls, suggesting their bodies became more efficient at processing glucose even with higher natural sugar intake.
Breaking the Sugar Stereotype
Previous mango research has produced mixed results, with some studies showing blood sugar benefits and others finding minimal effects. Most earlier trials ran for shorter periods than this 24-week study, which represents the longest controlled investigation of daily mango consumption in people with prediabetes.
The participants were adults aged 50-70 with body mass indexes between 18.5 and 34.9 and fasting blood glucose levels indicating prediabetes. Researchers excluded people who regularly ate mangos to avoid adaptation effects that might skew results.
Both groups maintained their usual diets and activity levels throughout the study, making the mango the primary variable driving the observed changes.
Rethinking Fruit and Diabetes Risk
The findings add to growing evidence that focusing on where sugar comes from and how it’s packaged in foods matters more than total sugar content. Systematic reviews show that whole-fruit interventions can modestly improve blood sugar control, with the largest benefits occurring in prediabetes rather than established diabetes.
Emerging research suggests that replacing added sugars with the natural sugars found in whole fruits associates with better body composition profiles, supporting an approach that considers sugar source rather than treating all sugars equally.
For the millions of Americans with prediabetes, the study suggests a simple dietary swap might help prevent progression to Type 2 diabetes. Rather than avoiding fruit due to sugar concerns, replacing one processed snack daily with whole fruit could provide measurable metabolic benefits.
With regard to the study’s sample, it included mostly White participants, and baseline differences between groups in sex, race, and ethnicity were handled through statistical adjustment. This is a common approach in clinical trials when randomization doesn’t perfectly balance demographic characteristics.
The bottom line challenges decades of dietary advice: when it comes to blood sugar and body composition, a mango’s natural package of fiber, nutrients, and bioactive compounds appears to trump its sugar content. For people walking the tightrope between normal blood sugar and diabetes, the choice between processed and whole foods might matter more than sugar grams on a nutrition label.
Paper Summary
Methodology
Researchers conducted a 24-week randomized controlled trial with 23 adults aged 50-70 who had prediabetes. Participants were randomly assigned to eat either 300 grams of fresh Tommy Atkins mango daily or an isocaloric granola bar. The study measured fasting blood glucose, HbA1c, insulin sensitivity, and body composition at baseline and at 6, 12, and 24 weeks. Participants maintained their normal diets and activity levels throughout the study period.
Results
The mango group showed significantly lower fasting blood glucose at 24 weeks compared to controls. Their HbA1c levels remained stable while the control group’s increased significantly. Insulin sensitivity improved in the mango group, with reduced insulin resistance. Body composition changes included a borderline significant decrease in body fat percentage and a significant increase in fat-free mass in the mango group, while the control group showed increases in BMI and waist-to-hip ratio.
Limitations
The study had a small sample size of 23 participants with limited racial and ethnic diversity. Baseline differences existed between groups in sex, race, and ethnicity distribution. The statistical power was calculated only for the primary outcome of fasting blood glucose. Dietary intake was self-reported rather than objectively measured, and the study didn’t adjust for multiple comparisons in secondary analyses.
Funding and Disclosures
The National Mango Board provided funding for this study. The authors declared no conflicts of interest and stated that the funders had no role in study design, data collection, analysis, interpretation, or manuscript preparation.
Publication Information
Basiri, R.; Dawkins, K.; Singar, S.; Ormsbee, L.T.; Akhavan, N.S.; Hickner, R.C.; Arjmandi, B.H. “Daily Mango Intake Improves Glycemic and Body Composition Outcomes in Adults with Prediabetes: A Randomized Controlled Study,” published online in Foods August 26, 2025.
I would like to point out a glaring mistake made by the person who interpreted the scientific publication and wrote this article. Anyone with any legitimate scientific background would understand the role of the “control” in both the scientific endeavor as well as the written interpretation of the published “science”. I am pointing out the fact that the SFStudy Finds author does not know/understand what a “control” is in a scientific experiment nor how to represent it in authoring an article about it. Here is the definition of the control: “In a science experiment, a control serves as a standard for comparison, providing a benchmark to measure the effects of the variable being tested. It is typically a control group, which is not exposed to the independent variable, or controlled variables (also called constants), which are factors deliberately kept the same throughout the experiment to ensure that observed changes are solely due to the independent variable.”
In this experiment there was no control (but had 2 variables) despite the author of this article referring to it. The control was NOT the snack bar as the snack bar was a variable as was the mango. This experiment was poorly done with no control. The control SHOULD have been a few individuals who ate neither the snack back nor the mango. In order to get any MEANINGFUL results the comparison of the mango blood sugars should have been compared to the persons who ate neither the mango nor the snack bar. The same with the snack bar-eating group. Lacking a legitimate control, there is no real information gained in this “research”. The research itself was poorly constructed and the writer of this article apparently had insufficient scientific background to understand this most basic foundation of scientific experimental principles.
Yet again SFStudy Finds presents inaccurate and/or dubious articles to the public. Yet AGAIN I am calling them out for insufficient knowledge base and presenting misinformation to the public for the sake of publishing an online newsletter.
You should be ashamed of yourselves.
As a retired researcher, clinician and the chair of a hospital research ethics board (REB) in Canada, I found that your “Funding and Disclosures” to be excellent for clearly stating that … “The National Mango Board provided funding for this study. The authors declared no conflicts of interest and stated that funders had no role in study design, data collection, analysis, interpretation, or manuscript preparation.” I also appreciated the fact that your review of this study provided the reader with a section entitled “Limitations” that described the limitations of the study that provides education to the reader as to how the study could be improved
I would suggest that “Funding and Disclosures” sections should be expanded to specifically define the what is meant by the phrase “The authors declared no conflicts of interest”. I bring this issue to your attention because in my professional career, I have been confronted many times that a researcher’s definition of a “conflict of interest” excludes desirable benefits that may knowing or unknowingly bias the professional judgement of the researcher in the favor of the private research funders. Sadly, when a possible conflict of interest has been brought to the researcher’s attention, a common reply was that the “monetary” or “non-monetary gift” that they accepted did not affect their professional judgement and that they will keep the gift despite the fact that they did not give something of equal value in return.
Possible conflicts of interest should include but not limited to: a) the receipt from the private research funder any monetary/non-monetary gifts. These gifts may include but are not limited to items such as paid travel expenses for professional conferences (e.g. transportation, hotel/meals, conference registrations fees) where the researcher is not the presenter of a research project at the conference, b) “All-inclusive holiday” educational conferences for researchers that may include their spouses and the researcher is not a presenter at the conference, c) any previous relationship(s) with private research funder (i.e. an individual or organization) such as but not limited to previous employment or a previous research oriented placement such as an internship (paid or unpaid).
Thank you for this opportunity to offer my suggestions to improve the disclosure between researchers and their funding sources.