Judith Curry has a (somewhat tongue-in-cheek) look at the links between climate change and obesity.

One of the two references is to the care2 website.

Consider the three alleged “links” between climate change and obesity that Dr Curry summarised:-

• Rising inactivity rates because of hot temperatures
  
• Drought-induced high prices on healthy foods
  
• Food insecurity promotes unhealthy food choices
  

Rising inactivity is commonly thought to be due to less manual work, the rise of the car and evermore staring at the TV or computer. If a rise of 0.8C in temperature were a major factor then in Britain you would see (for instance) the Scots being more active than those in the South of England, or people being more active in winter than summer. In both cases the opposite is true.

Drought-induced high prices would have to show that droughts were the main cause of high prices of health foods compared to junk foods. Maybe convenience and taste have something more to do with the preference for unhealthy diets. Also you would need to show that rising food prices are connected to decreasing crop yields. Biofuels may have more with the rising food prices.

Food insecurity diminishes as per capita income rises, whilst obesity increases. That is the poorest of the world have hunger as a problem, whilst the rich countries have obesity as a growing problem. Obesity may be a problem of the poor in the developed nations, but food as a whole is not a problem.

The above article is a very extreme example of

The underdetermination thesis – the idea that any body of evidence can be explained by any number of mutually incompatible theories

Kuhn Vs.Popper: The Struggle for the Soul of Science – Steve Fuller 2003 Page 46.

Kevin Marshall