When was the study called PURE started?

Choices:
A. not enough information
B. 7 years ago
C. 2 years ago
D. 4 years ago
7 years ago
Called the PURE (Prospective Urban Rural Epidemiology) study, this was a very large observational study looking at the link between fat and carbohydrate consumption and longevity in 18 countries across 5 continents. Running for 7 years and involving over 135,000 people, this was a very big study so its conclusions are right to take notice of.
The key finding from the work that attracted the most media attention was that a high carbohydrate diet was linked with a higher risk of earlier mortality, whereas total fat and individual types of fat were related to a lower risk of earlier mortality.
Digging deeper into the study, the research team found that global diets consisted of 61 percent energy coming from carbohydrates and 24 percent energy from fats. And while those in the highest carbohydrate consumption group (a whopping 77 percent of energy) had a higher risk of earlier death, it wasn’t cardiovascular disease they were dying from. What those other causes of death were exactly is unclear. Perhaps getting hit by a car running for a Mars Bar was one of them as a recent commenter on my Facebook page theorised.
A paradigm shift? Not quite
Does this study turn on its head ‘everything we knew about nutrition?’ Not quite. And here’s why.
Before the PURE study, there were many studies showing the opposite link between carbohydrates and longevity. So, when a conflicting study comes along, this grabs the media spotlight for the day.
Here is just one example – a major systematic review and meta-analysis from 2013 involving 17 individual studies and over 242,000 people showing a higher risk of earlier mortality as carbohydrate intake decreased. And this is the problem at times with observational research in that two studies can give polar opposite results so the findings of the PURE study should be seen through this filter.
I’m not going to pick apart the PURE study for its flaws. Such issues are consistent across all observational studies no matter if the conclusions support consensus views or not. What is of value to look at is the positive messages the study gave and how when you look at the full research field, it takes you back to some pretty sensible advice.