I just found this gem from the Alaska Legislature 2015. Rep. Paul Seaton chairs a vitamin D discussion. Natives used to dry Salmon under the sun, greatly increasing vitamin D. Now their vitamin D levels are way down, since most eat a western diet in addition to no longer using this traditional drying technique.

The vitamin D discussion is on overcoming Rickets, which only requires 20 ng/ml blood levels, whereas immune health (as for Covid) requires 50 ng/ml.

Video of the Alaska State Legislature

03/12/2015 03:00 PM HEALTH & SOCIAL SERVICES

56:15 Rep. Paul Seaton, Chair says they lowered the preterm delivery rate to 7% through a vitamin D program called “Protect Our Children Now.”

1:17:30 Vitamin D presentation by JAY BUTLER, MD, Chief Medical Officer/Director Division of Public Health

133:30 Alaska State Rep. Paul Seaton explains how Alaska Natives traditionally dried Salmon, marine and land animal meats in the sun, which greatly increased their vitamin D levels.

4:27:47 PM

CHAIR SEATON …questioned the modern traditional technique for drying salmon hung under plywood or tarps, and he pointed out that, as this food preservation technique no longer included exposure to sun while drying, there was a tremendous difference in the amount of Vitamin D created as a supplement. He pointed out that the traditional preservation technique was for foods to be sun dried, which increased the vitamin D level in foods.

1:18:15 ROSALYN SINGLETON, Staff Physician, Section of Epidemiology, Division of Public Health, Department of Health and Social Services presented a PowerPoint titled “Rickets and Vitamin D Deficiency in Alaska Native Children.”

4:14:38 PM

DR. SINGLETON referenced slide 3, “Vitamin D deficiency,” stating that this nutritional deficiency had increased in prevalence since the 1990s. She reported that the risk factors included insufficient sun exposure, an obvious issue in Alaska. She described rickets as a state of extreme vitamin D deficiency in growing bone, and had a peak incidence between 3 and 18 months of age. She detailed that the wrists and ribs swelled, and the legs bowed, with occasional seizures from low calcium levels. She moved on to slide 4, “Definition of Vitamin D Deficiency,” which she defined as a level of 25OHD below 20 ng/ml, and was associated with a higher risk for skeletal effects. She shared that Vitamin D insufficiency was described as below 21 – 29 ng/ml, with increased risks for exo-skeletal effects which were not as clearly understood.

DR. SINGLETON addressed slide 5, “Screening for Vitamin D Deficiency,” and said that the evidence was insufficient to recommend universal screening for Vitamin D deficiency, with advised screening only in children and adolescents having conditions associated with reduced bone mass and/or recurrent fractures. She noted that screening was recommended for at-risk individuals which included children with obesity, and black and Hispanic children, although this was somewhat controversial as it would involve screening and retesting large numbers of children without any evidence of cost benefit to reducing fractures. She said that salmon and other oily fish had some of the highest Vitamin D contents of any foods, slide 6, noting that canned sockeye salmon had more than 700 IU of Vitamin D. She pointed out that Alaska Natives with a high marine subsistence diet had high intake of Vitamin D, while maintaining high levels of Vitamin D. …

She explained that there was interest in the potential connection between apparent increases in rickets and the known decline in marine subsistence diet among Alaska Natives. Prior to the 1960s, a significant proportion of energy was derived from the marine subsistence diet, although more recent food intake surveys showed that only about 6 percent of energy in younger people came from marine subsistence foods. She referenced an interim study in the late 1990s, that showed that 21 percent of energy came from native foods, and that 82 percent of the Vitamin D came from those same subsistence foods. She spoke about a study, slide 11, “Serologic Survey of Biomarkers for Traditional Marine Diet and Vitamin D Levels in YK Delta Childbearing-aged Women,” that explored how the intake of traditional marine foods and serum Vitamin D levels had changed in child bearing women.