We reviewed data on the American diet from 1800 to 2019. Methods: We examined food availability and estimated consumption data from 1800 to 2019 using historical sources from the federal government and additional public data sources. Results: Processed and ultra-processed foods increased from <5 to >60% of foods. Large increases occurred for sugar, white and whole wheat flour, rice, poultry, eggs, vegetable oils, dairy products, and fresh vegetables. Saturated fats from animal sources declined while polyunsaturated fats from vegetable oils rose. Non-communicable diseases (NCDs) rose over the twentieth century in parallel with increased consumption of processed foods, including sugar, refined flour and rice, and vegetable oils. Saturated fats from animal sources were inversely correlated with the prevalence of NCDs. Conclusions: As observed from the food availability data, processed and ultra-processed foods dramatically increased over the past two centuries, especially sugar, white flour, white rice, vegetable oils, and ready-to-eat meals. These changes paralleled the rising incidence of NCDs, while animal fat consumption was inversely correlated.
Annual total caloric and macronutrient availability per capita from 1909 to 2010 (Source: USDA ERS).
Full Paper - http://dx.doi.org/10.3389/fnut.2021.748847
What I find frustrating is we know what complaints will be made about this data in advance of doing the study, so why did they do this study? I get that they brought something new by articulating it well and bringing some data sources together in a slightly different way and so on, but what meaningful, tangible change is there to our knowledge with this study?
To be clear, no shade on the researchers, they did the best with the system they have. I mean the system as a whole. When we have study after study which shows that saturated fat is not the cause of heart disease and one side of the argument just refuses to change their mind to match the evidence it seems the scientific system is broken and will not move forward.
A conference on an issue like this would also not work because those same issues would turn up. A panel with 10 researchers would include many who are directly funded by industry. They can’t leave that baggage at the door and think clearly. That simply isn’t human nature. We can’t expect people who have a vested interest in the outcome going a certain way to act with detachment and clarity. They are and always will be biased.
but what meaningful, tangible change is there to our knowledge with this study?
It gives weight to alternative theories of modern chronic disease and demonstrates people HAVE BEEN following the anti-saturated fat messaging.
When we have study after study which shows that saturated fat is not the cause of heart disease and one side of the argument just refuses to change their mind to match the evidence it seems the scientific system is broken and will not move forward.
Sadly when the US dietary guidelines did change recognizing saturated fat as benign and health some, people immediately turned it into a political issue rather then a health issue. So we need this, the JACC Saturated fat review, public policy change, dietitian change, and most importantly persistance to outlast the pharmaceutical financial interest in selling medicine that can lower a intermediate metric.
The standard criticisms will apply:
- Lack of association is not the same thing as the lack of causation
- Historical trends has many confounding variables