Vitamin D3 Deficiency in America

https://www.sciencedirect.com/science/article/pii/S0271531710002599

https://www.scientificamerican.com/article/vitamin-d-deficiency-united-states/

Vitamin B12 Deficiency in America

 https://ods.od.nih.gov/factsheets/VitaminB12-HealthProfessional/

https://www.ncbi.nlm.nih.gov/books/NBK441923/

https://www.ars.usda.gov/news-events/news/research-news/2000/b12-deficiency-may-be-more-widespread-than-thought/

Omega 3 Deficiency in America

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3992162/