4 ms·

Does anyone know whether as a matter of epidemiology, prevalence of this virus matches any part of an obesity map like this: https://www.hsph.harvard.edu/obesi

Does anyone know whether as a matter of epidemiology, prevalence of this virus matches any part of an obesity map like this: https://www.hsph.harvard.edu/obesity-prevention-source/map-of-global-obesity-trends/ https://www.hsph.harvard.edu/obesity-prevention-source/map-o... My guess is this virus would be equally prevalent in North America and Western Europe and therefore as a matter of public health has no impact whatsoever on obesity. Instead, in my reading in North America it is very difficult to eat in a healthy way and in my personal experience people are eager to find reasons other than the food supply, tastes, and behaviors. If, on the other hand, this virus was prevalent in North America but very rare in Western Europe it would give some indication that perhaps it was worthy of attention. I would like to know if anyone has applied this differential.

wcummings 10y ago
I really doubt this virus has anything to do with obesity in aggregate, the causes are pretty well understood. >in my reading in North America it is very difficult to eat in a healthy way and in my personal experience people are eager to find reasons other than the food supply, tastes, and behaviors. You hit the nail on the head, this is probably why this story got as many votes as it did.
zbjornson 10y ago
There's actually a lot of data on this because adenoviruses are popular vaccine vectors of study right now, and the selected serotype must be one that as few people as possible have titers against, so researchers test random people for immunity. For example, [0] (2010) reports that ~5% of people in the US were positive for Ad36, 35% Thailand, 52% South Africa, 91%(!) Malawi, 88% Cameroon, 48% Botswana, 43% Brazil. Malawi, Cameroon, Thailand and Botswana are solidly in the lower % obesity parts of the map that you linked to, while the US has the lowest antibody prevalence and highest obesity. They don't have Ad36 data for Europe unfortunately, but ... Ad36 is not the only adipogenic (fat-causing) serotype. Ad5, 9, 31, 36 and 37 are all correlated or linked to being adipogenic [1]. The above paper [0] has numbers for Ad5 if you're interested: Europe was 39% negative, US 31%, the African countries 10-13%, Brazil 18%. [0] https://www.ncbi.nlm.nih.gov/pubmed/19925902 https://www.ncbi.nlm.nih.gov/pubmed/19925902 [1] https://www.ncbi.nlm.nih.gov/pubmed/26352001 https://www.ncbi.nlm.nih.gov/pubmed/26352001
- fragsworth 10y ago
  Depending on how it spreads, the virus could appear to be more common in populations where there has been historic starvation, because it seems like it would help you survive in those situations.
  - VLM 10y ago
    And the flip side of the coin is it would cause extreme obesity if by some economic miracle carb intake were totally unlimited and trended toward infinity. So it would eventually (on a very long scale) be bred out of economic areas of infinite carb availability. But eventually is far too long and too much human suffering, so temporarily we're very very fat. As a hypothesis you could create a mathematical model where the faster a country industrializes or otherwise moves beyond bare subsistence and periodic famine, the harder the spike of obesity. That's not a bad match to existing obesity maps, especially when the obesity map is corrected for country of origin not current geographic location.
- logicallee 10y ago
  I greatly would have preferred to see Western Europe instead of the countries in your second paragraph, because while tastes and convenience differ, income is comparable in European capitals especially, and people can eat at McDonald's if they want, with the same impact on their budget. Whereas some of your other countries differ substantially in all metrics from N. America (specifically the U.S. In particular the U.S. has per capital income that is a multiple of each of those countries [1] - in terms of purchasing power, Thailand, South Africa, Malawi, Cameroon, Botswana, Brazil are at $16,130 - $13,209 - $1,126 - $3,148 - $16,415 - $15,646 respectively (the hyphens are just my separators) to the U.S. at $56,084. The food choices and culture would also very radically differ. While Western Europe and North America have differing food cultures, habits, and especially convenience and availability, at least the purchasing power is comparable, the worst offenders (e.g. cola with sugar, cheap fast food) are equally available and many cultural aspects (general industrialization and urbanization, amount people work physically) are at least roughly similar. The countries you listed are just very different across all of these points, as far as I know. Even an American who goes to Thailand isn't going to eat the same as in America - whereas while going travelling in Europe, they well might eat very comparably. So while you support the argument I was making, I actually would prefer to see data about incidence in Western Europe - not the countires you listed. [1]https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)_per_capita https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)... - (I'm using the first column, International Monetary Fund (2015))
VLM 10y ago
Its interesting that obesity map is indistinguishable from a map of type-II diabetes. A reasonable hypothesis, given a virus that sucks glucose out of the blood and fills tissue with fat, is that the higher blood glucose levels of type 2 diabetes would supercharge fat production in those infected with the virus. So if the patient is infected, and their blood sugar goes up 20%, their fat production will go up 20% regardless of diet. I can see how that would quickly result in very fat diabetes patients. It would be fascinating to separate the disease symptoms of type-2 diabetes that are caused solely by obesity from those caused solely by blood sugar. Obviously it would be easier to recover from type-2 diabetes related obesity if a viral infection that essentially creates fat were not turbocharged because of blood chemistry reasons at the same time as the patient is trying to lose fat. Another interesting study would be children. Anecdotally they can eat hundreds of pounds of sugar and dozens of gallons of corn syrup and remain skinny, until suddenly, perhaps after infection, or perhaps after their pancreas gives out causing a blood sugar rise, they explode in fatness given the same or even lower carb intake. Quite possibly due to the infection, high blood sugar is causing fatness rather than the other way around, with some interesting implications for treatment. Normally artificially lowering blood sugar would seem to shove it into the fat generation path, but if high blood sugar is turbo charging the infection, perhaps lower blood sugar levels would paradoxically cause weight loss... You could also run a study of low carb diet success and failure vs infection rate. People with low level semi-diagnosed type-2 diabetes (its a spectrum not a binary) should respond extremely well to a low carb weight loss diet... uninfected people or people infected but without type-2 symptoms should not respond very well to a low carb weight loss diet.

wcummings 10y ago

I really doubt this virus has anything to do with obesity in aggregate, the causes are pretty well understood. >in my reading in North America it is very difficult to eat in a healthy way and in my personal experience people are eager to find reasons other than the food supply, tastes, and behaviors. You hit the nail on the head, this is probably why this story got as many votes as it did.

zbjornson 10y ago

There's actually a lot of data on this because adenoviruses are popular vaccine vectors of study right now, and the selected serotype must be one that as few people as possible have titers against, so researchers test random people for immunity. For example, [0] (2010) reports that ~5% of people in the US were positive for Ad36, 35% Thailand, 52% South Africa, 91%(!) Malawi, 88% Cameroon, 48% Botswana, 43% Brazil. Malawi, Cameroon, Thailand and Botswana are solidly in the lower % obesity parts of the map that you linked to, while the US has the lowest antibody prevalence and highest obesity. They don't have Ad36 data for Europe unfortunately, but ... Ad36 is not the only adipogenic (fat-causing) serotype. Ad5, 9, 31, 36 and 37 are all correlated or linked to being adipogenic [1]. The above paper [0] has numbers for Ad5 if you're interested: Europe was 39% negative, US 31%, the African countries 10-13%, Brazil 18%. [0] https://www.ncbi.nlm.nih.gov/pubmed/19925902 https://www.ncbi.nlm.nih.gov/pubmed/19925902 [1] https://www.ncbi.nlm.nih.gov/pubmed/26352001 https://www.ncbi.nlm.nih.gov/pubmed/26352001

fragsworth 10y ago
Depending on how it spreads, the virus could appear to be more common in populations where there has been historic starvation, because it seems like it would help you survive in those situations.
- VLM 10y ago
  And the flip side of the coin is it would cause extreme obesity if by some economic miracle carb intake were totally unlimited and trended toward infinity. So it would eventually (on a very long scale) be bred out of economic areas of infinite carb availability. But eventually is far too long and too much human suffering, so temporarily we're very very fat. As a hypothesis you could create a mathematical model where the faster a country industrializes or otherwise moves beyond bare subsistence and periodic famine, the harder the spike of obesity. That's not a bad match to existing obesity maps, especially when the obesity map is corrected for country of origin not current geographic location.
logicallee 10y ago
I greatly would have preferred to see Western Europe instead of the countries in your second paragraph, because while tastes and convenience differ, income is comparable in European capitals especially, and people can eat at McDonald's if they want, with the same impact on their budget. Whereas some of your other countries differ substantially in all metrics from N. America (specifically the U.S. In particular the U.S. has per capital income that is a multiple of each of those countries [1] - in terms of purchasing power, Thailand, South Africa, Malawi, Cameroon, Botswana, Brazil are at $16,130 - $13,209 - $1,126 - $3,148 - $16,415 - $15,646 respectively (the hyphens are just my separators) to the U.S. at $56,084. The food choices and culture would also very radically differ. While Western Europe and North America have differing food cultures, habits, and especially convenience and availability, at least the purchasing power is comparable, the worst offenders (e.g. cola with sugar, cheap fast food) are equally available and many cultural aspects (general industrialization and urbanization, amount people work physically) are at least roughly similar. The countries you listed are just very different across all of these points, as far as I know. Even an American who goes to Thailand isn't going to eat the same as in America - whereas while going travelling in Europe, they well might eat very comparably. So while you support the argument I was making, I actually would prefer to see data about incidence in Western Europe - not the countires you listed. [1]https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)_per_capita https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(PPP)... - (I'm using the first column, International Monetary Fund (2015))

VLM 10y ago

Its interesting that obesity map is indistinguishable from a map of type-II diabetes. A reasonable hypothesis, given a virus that sucks glucose out of the blood and fills tissue with fat, is that the higher blood glucose levels of type 2 diabetes would supercharge fat production in those infected with the virus. So if the patient is infected, and their blood sugar goes up 20%, their fat production will go up 20% regardless of diet. I can see how that would quickly result in very fat diabetes patients. It would be fascinating to separate the disease symptoms of type-2 diabetes that are caused solely by obesity from those caused solely by blood sugar. Obviously it would be easier to recover from type-2 diabetes related obesity if a viral infection that essentially creates fat were not turbocharged because of blood chemistry reasons at the same time as the patient is trying to lose fat. Another interesting study would be children. Anecdotally they can eat hundreds of pounds of sugar and dozens of gallons of corn syrup and remain skinny, until suddenly, perhaps after infection, or perhaps after their pancreas gives out causing a blood sugar rise, they explode in fatness given the same or even lower carb intake. Quite possibly due to the infection, high blood sugar is causing fatness rather than the other way around, with some interesting implications for treatment. Normally artificially lowering blood sugar would seem to shove it into the fat generation path, but if high blood sugar is turbo charging the infection, perhaps lower blood sugar levels would paradoxically cause weight loss... You could also run a study of low carb diet success and failure vs infection rate. People with low level semi-diagnosed type-2 diabetes (its a spectrum not a binary) should respond extremely well to a low carb weight loss diet... uninfected people or people infected but without type-2 symptoms should not respond very well to a low carb weight loss diet.