vitamin d

Ivor Cummins gives an 82-minute presentation on the history and science of vitamin D and human health. He draws on expert interviews to argue that sun exposure and vitamin D status are linked to many chronic diseases.

Dr. John Campbell reviews studies on vitamin D deficiency and immunity, including links to influenza and COVID-19, with Public Health England advice. He walks through the sources he cites.

Dr. John Campbell reviews studies on vitamin D and immunity, including research on respiratory infections, during the early COVID-19 period.

Veritasium examines whether food has become less nutritious, weighing soil depletion, selective breeding and rising atmospheric CO2. It evidences nutrient decline even in weeds over a century and ties it to faster plant growth.

Veritasium shows what the world looks like through a UV camera. It covers how pigments absorb UV, how fluorescence works, and how UV imaging reveals sunscreen effectiveness and skin damage.