The other night I got curious as to whether the numbers of Type 1 and Type 2 diabetics around the world are correlated- that is, whether countries with higher rates of Type 1 diabetes also have higher rates of Type 2, and vice versa. I assumed there’d be a big overlap but maybe some small interesting outliers to look at. What I found was a more than a few interesting outliers, and some really wild data swings.
This fantastic map view at worldbank.org shows numbers from 2015 and right off the bat the four highest listings (Nauru, Mauritius, Marshall Islands & Palau) are all tiny Southern island countries, as are plenty more further down but still high in the list. But this shows us a weighted average for prevalence of both Type 1 and Type 2 and despite the interesting groupings of countries, doesn’t show us anything between the two types.
Next I looked at this 2011 diabetes.co.uk list of countries by prevalence of Type 1 diabetes in children (0-14 years old) and we immediately see some radical differences. Only 2 of the top 5 countries from the other map even appear in this list and here there’s a much stronger grouping towards western and northern Europe, though some of this could be because Europe tends to have better medical data sourcing than many other areas. Interestingly, Saudi Arabia is one of the countries highest and at a similar rate in both lists, likely due to a number of factors such as a high genetic susceptibility, a cultural diet rich in high-calorie & high-carb foods and increased obesity and poor diet. Headlines from this data have cited everything from fast food to cleanliness being part of the explanation but based on the fact that many of these are northern European countries where people spend a lot of time in doors I think a more interesting thing to look at or draw from this data is the effects of lowered Vitamin D in correlation to Type 1 diabetes since we’re very aware of the deficiency of Vitamin D in people both before and after Type 1 diagnoses not to mention the many conditions in large part correlating melanin, vitamin D and the effects of Type 1 diabetes and impaired immune system like Vitiligo and Acanthosis nigricans. The links between Vitamin D and diabetes are still not understood but the data and results commonly overlap and I find it interesting, if nothing else when looking at these data sets.
Since we know that both Type 1 and Type 2 diabetes rates are on the rise world-wide, and that both (though less correlated in Type 1) are linked to obesity it’s understandable that rates in Europe are high but are increasing world wide. While this is purely a glance at the data and a very poor comparison of data sets, what isn’t clear is the visible difference in numbers of Type 1 and Type 2, especially considering an estimated 90% of diabetics are Type 2. It leaves me searching for more complete data and wondering how the two vary locally as well as globally.