

That's DDT. We sprayed so much of it that it is STILL in the ground in the soil layer to this day. We also had leaded gasoline back then. Glyphosate was invented in 1961. BPA began to be used in plastics in the 50s.PFAS began to be used in the 40s. We had widespread asbestos. Various toxic aerosols. Years of modern vehicle farming (and regular vehicle pollution) depositing heavy metals via exhaust and tires into the ground, including from leaded gasoline (was never cleaned up). And ofc mercury contamination in many areas from old gold mining practices (stopped bc of FDR and WW2), along with heavy metal toxicity from all mining practices. And more! So much more!
To fix the food system, we would have to ban vehicles and harmful pesticides from fields and bioremediate the fields for years.
And regardless, all of those toxins I listed above, have to be dealt with by the body. Which causes, you guessed it, vitamin deficiencies because your body needs them to process these poisons out. Hello, your fucking LIVER is the main storage unit for fat soluble vitamins (along with fat cells and bone marrow) because it dispatches them as needed through your lymph (aka your immune system).
Last but not least, we synthesized and understood the need for fat soluble vitamins back in the fucking 50s and before. Yes, nearly a century ago. People also ate organ meat like liver and heart back then which have substantial fat soluble vitamins in them.
Here, look:
1948: Lupus treated with vitamin e https://jamanetwork.com/journals/jamadermatology/article-abstract/521956
1979: Vitamin E effective therapy for lupus. https://pubmed.ncbi.nlm.nih.gov/759121/
2023: Lupus patients shown to have lower vitamin e, improved w vitamin e supplementation https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2020.01477/full#B163