Mangoes are not able to treat diabetes.

When it comes to the scientific community, there is a humorous cliche. It has come to the attention of large agricultural corporations that consumers are more likely to purchase their goods if they include a health halo. Investing in a few scientific research studies is the most effective method for making your product seem to be healthy. This is true whether you are selling honey, blueberries, walnuts, or even wasabi sauce. Don't worry about it if the studies come out negative! Simply report them as if they were affirmative, taking into account the fact that the likelihood of anybody ever checking them is...extremely minimal.

The mango is the most recent and entertaining addition to this stereotype. Indeed, I am now able to pronounce the phrase "Big Mango" without any irony. In recent times, the delectable tropical fruit has garnered a significant amount of interest from the media, with claims being made that it has the potential to treat or even prevent diabetes. In actuality, these headlines are based on some extremely dubious study that was supported by the mango-growing business.

Hilarious thing. Sometimes the truth truly is better than fiction.

The Science

The recent research that has everyone so fired up about mangoes was a modest clinical experiment. The scientists randomised 48 overweight persons to either consume frozen mango or sugar-sweetened Italian ice smoothies for a month, then compared the groups. The major goals of the trial were a broad variety of inflammatory markers and certain tests of the gut microbiota, and there were secondary outcomes that looked at insulin sensitivity, blood glucose, and some other elements of health.

Given the sensational headlines, you’d believe that the authors uncovered some fantastic outcomes. Maybe mangoes dramatically reduce blood glucose. Perhaps they slashed inflammation. Maybe even induced weight reduction or enhanced the gut microbiota.

Except, none of this occurred. The persons who ate mangoes had somewhat HIGHER blood glucose than those in the control group. They also had increased cholesterol and triglycerides. Despite assessing a broad variety of inflammatory markers, there was no hint of any difference between the two groups on any of them at the conclusion of the experiment. I couldn’t discover any information in this study concerning the microbiome – possibly the authors are planning another publication on it in the future.

So where has the buzz come from? Well, there was one very little difference. At the conclusion of the experiment, the mango group had somewhat superior scores on two measures of insulin. Specifically, they exhibited lower fasting insulin levels and somewhat improved HOMA-IR. The p-values for these disparities were 0.05 and 0.03, respectively, which, for anybody who understands much about the replicability dilemma, is…telling.

These distinctions are straightforwardly pointless. They are modest enough to have little to no therapeutic advantage – if nothing else, the average insulin readings for both groups were normal. There was no change in blood glucose, and perhaps more tellingly, there was no difference in the key other insulin measure that the authors evaluated. They had their patients come in and undergo an oral glucose tolerance test, where you collect samples at baseline, 1 hr, and 2 hr. The baseline values were statistically substantially different, but the total results were not.

The authors also tested a relatively meaningless number. They looked at the difference between the two groups at the conclusion of the experiment, but that’s not what we worry about. We are interested in the change scores – the amount that these values changed about as a result of the therapy. If you look at the baseline readings, you can see that the major reason why the insulin levels varied at the conclusion of the experiment was because the control group became significantly worse over 4 weeks.

Bottom Line

There are a few ways we may interpret these data. One is that mangoes don’t enhance any health indicators save the two that were statistically substantially different. This is clearly an extremely implausible notion since it flies in the face of physiology. It’s also plausible that the control therapy — which, recall, was just sorbet — is deliberately detrimental for your insulin levels.

But the most probable take-home here, in my view, is that these are exactly the outcomes we’d expect to see if mango smoothies for a month offered no benefit to human health. This is precisely what I’d anticipate if you were to do a trial on something that didn’t work.

The issue then becomes why the findings were reported up as if they demonstrated an advantage for mangoes. It’s impossible to identify the cause, but if I were a pessimistic person, I’d remark that the research was financed by the US National Mango Board, a legitimate business entity that strives to raise sales of mangoes.

Yes, Big Mango financed a lousy study that somehow indicated an advantage for mangoes even if it didn’t actually. As I said, funny things.

I could delve into the shortcomings in the experiment itself — the concerns with blinding, the absence of information concerning allocation concealment, and the probable issues with the control smoothies — but honestly there’s not much point. The research was great as far as randomised trials go, but it was also very substantially negative.

There’s no reason based on these findings to add mango to your diet. It’s a delightful, lovely fruit that you should already be eating, but it probably doesn’t treat diabetes.