The Study
Back to the pre-industrial age? FAOSTAT statistics of food supply reveal radical dietary changes accompanied by declining body height, rising obesity rates, and declining phenotypic IQ in affluent Western countries
This study looks at big trends in how much food countries eat over many years and sees if those trends match up with how tall people are or how many get sick. It doesn't follow individual people or test diets — it just notices patterns on a map. So it can say 'countries that eat more cereal seem to have shorter kids,' but it can't say 'eating cereal makes kids short.'
Analysis score
Maximum 0 for a editorial/opinion.
Where the score came from
A long time ago, people ate more meat and dairy and less sugar and white bread. Now, many kids eat more sugar and grains and less meat. This might be why they’re not growing as tall, getting fatter, and maybe even thinking a little less clearly.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 50 / 100
Quality score
Based on clinical experience or non-systematic literature reviews. The lowest level of evidence as they are most susceptible to bias and personal perspective.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Yes—this suggests what children eat during growth years could shape their height, weight, and even brain development decades later.
- 2Countries with more dairy and pork vs.
- 3cereals had taller men.
- 4When sugar and refined carbs went up, diabetes and obesity rose 6–11 years later.
- 5IQ dropped in some countries after protein quality fell.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Annals of Medicine
Year
2025
Authors
P. Grasgruber
Related Content
Claims (7)
Diets eaten by humans before industrialization provided more protein for each calorie consumed than the diets commonly eaten today.
In affluent Western countries, a shift away from animal proteins like dairy and pork toward more cereals and sugary carbohydrates coincides with a slowdown in the historical increase of adult male height, indicating that nutritional changes during childhood and adolescence may be affecting growth.
In countries where people consume more animal protein from dairy and pork relative to cereal proteins, average male height tends to be taller. This pattern is observed across 136 populations.
People in Western countries who eat more high-glycemic carbohydrates like sugar, sweeteners, potatoes, and refined grains have a higher rate of developing type 2 diabetes, with the strongest link appearing 6 to 9 years after increased consumption.
In Denmark and Norway, decreases in average IQ scores over time have been linked to lower quality of dietary protein consumed 7 to 11 years earlier, suggesting that nutrition during early childhood may affect cognitive outcomes later in life.
Dietary guidelines for children in Western countries that limit animal proteins and favor plant-based foods may be linked to slower growth and lower cognitive performance, based on population-level data showing that higher intake of animal proteins correlates with better height and cognitive outcomes.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.