The 'epidemic' in the UK is actually quite small compared with other places.
The UK has a national prevalence of 5.9%, if we compare it with other countries we use a percentage, adjusted for the different age ranges in each country. This comparative percentage for the UK is 'only' 3.9%.
Here's a few other comparative percentages.
US. 9.39%, Somalia 7.29% , Kuwait 21.13%, India 9.11, China 8.64% ,Nauru 23.27%
(in all countries there are many who are undiagnosed and not included in these rates. This means that in the case of countries like China, India and many African countries these rates are just the tip of the iceberg.) World figures ,map and estimated undiagnosed rates here
http://www.idf.org/sites/default/files/Atlas-poster-2014_EN.pdf
One country that might give some clues as to why there is such an epidemic and maybe a little glimpse of how it can be reversed is Nauru , the tiny Island at the bottom of my list.
This Island very quickly became the richest population on earth. Mining destroyed the land but they had the wealth to import food. They no longer fished and farmed nor ate their traditional diet of fish and bread fruit, mangos, coconuts and root vegetables. Spam became almost the national dish along with deep fried chicken . The New Zealanders exported the fatty mutton flaps to them and the US found them a good outlet for turkey tails. . To accompany all this fatty meat was large amounts of Coca-Cola, ice cream and crisps (chips) . . They acquired vehicles and drove every where, in spite of the fact that their country is only 8.1 sq miles in area .
Result a sedentary lifestyle ,with little work fuelled by high quantities of both fat and sugar. Obesity rose, (probably welcomed initially because this culture, like many that have endured periodic famines prized fatness as a symbol of health). It then became the fattest place on earth , diabetes followed with the worlds's highest T2 diabetes rates , eventually affecting more than half of the middle aged population. At the same time younger and younger people were being affected.. Life expectancy was low.
Then the phosphate reserves were mined out, they lost all their investments through mismanagement , the money dried up and left them in a state of bad health with no employment and economic dependency.
However, they are no longer the place in the wold with the highest diabetes rates. It's still extremely high but it is falling. This is partly because of the death rate from complications (and Jared Diamond, see below suggests that those with susceptible genes are being lost from the gene pool) Perhaps more demonstratively, interventions aimed at returning people to more traditional diets have been implemented. There is a FAO target/scheme, funded with International aid. The aim is 30% of the food to be produced locally by 2015 and 70% by 2025 (hard as the mining polluted the land) Education has helped as have exercise interventions but on top of that less money for individuals to spend is also helping to reverse the process.
The Nauruns and other Pacific Islanders undoubtedly had a genetic propensity for diabetes but it didn't cause any problem until they changed to a lifestyle that included large quantities of foods and too little exercise. You can't blame one nutrient, their original diet included lots of carbs from starchy fruits plus protein and fat from fish. The modern one lots of fat and carbs in highly processed forms. The one thing all these recent foods have in common are that they are calorie dense and nutrient poor.
A similar process is taking place in Asia (former diets mostly rice and vegetables with little meat ) and in Africa.
The UK hasn't had such a drastic change. There has been change but over a lot longer, though undoubtedly accelerated in the last 20 years.
(Diamond suggests there has already been a loss of susceptible genes in the population over the last 200 or so years hence T2 effects fewer people. This isn't unchallenged though)
http://www.wsrn.sccs.swarthmore.edu/users/08/wnekoba/DoubleDiabetes.pdf )
It's true though that cheap processed foods are becoming ubiquitous. If you are relatively well off, you have a choice about what to eat but if you do have a genetic propensity, then just a little bit too much food could cause the damage over a number of years ( and you don't need many energy dense foods to provide too much; some flavoured coffees contain over 600 calories , and the calories in the Friday night take-away can be very high ) .
If you haven't the genetic propensity then you may just get fatter but not diabetic. (though eventually most researchers believe people will reach the point when fat storage no longer provides a buffer against diabetes, fat will get in the wrong places and diabetes will follow)
If you haven't the money and hence are more likely to eat lots of cheap energy dense foods, then you may follow that path very much more quickly. In either case can the individual be blamed?
Only a few can blame their genes completely. Undoubtedly there will be individual families where specific genetic variations increase the risk of T2 considerably but that's not most families. There are over 60 gene variations that predispose to diabetes but each individually only amounts to a very slight increase in risk . T2 diabetes is in Europe is only about 26% percent heritable
I don't think though that individuals can be blamed for the changes in food culture that affect them more severely than their neighbour.
For a video on Nauru, google Nauru - Paradise Ruined Vimeo : not specifically on diabetes but it plays a background part (particularly showing how complications affect people)
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