Chris Kresser took a look at the Lancet study, and pretty much shredded it:
Here is a link to his analysis, and a couple of excerpts from it:
https://chriskresser.com/will-a-low-carb-diet-shorten-your-life/
"Decades of nutrition research have myopically focused on the
quantity of protein, fat, and carbohydrate we eat, without considering the
quality. In my mind, this is perhaps the single biggest shortcoming of the bulk of nutrition research."
"I’m going to give you seven reasons why you should take the recent
Lancet study with a huge grain of salt:
- Using observational data to draw conclusions about causality
- Relying on inaccurate food frequency questionnaires (FFQs)
- Failing to adjust for confounding factors
- Focusing exclusively on diet quantity and ignoring quality
- Meta-analyzing data from multiple sources
Unfortunately, this study has already been widely misinterpreted by the mainstream media, and that will continue because:
- Most media outlets don’t have science journalists on staff anymore
- Even so-called “science journalists” today seem to lack basic scientific literacy"