Dr Cedric Garland has convinced me to take 5,000 to 6,000 IU of vit D daily.
There's is also this. Vitamin D Could Lower Risk of Developing Type 2 Diabetes, Study Sug...
The DINOMIT model makes a lot of sense to me, as a retired biology teacher familiar with cell tight junctions.
Low levels of vitamin D can impair the efficiency of mitochondria in your muscle cells. The good news is supplements can fix it.
The research shows for the first time that vitamin D levels are correlated with muscle efficiency, and that muscle aerobic metabolism improves with Vitamin D supplementation.
"Patients with vitamin D deficiency often experience symptoms of muscle fatigue. Our findings in a small group of patients with very low vitamin D levels show that muscle efficiency significantly improves when vitamin D status is improved.''
Smoking seems to lower levels of vitamin D, and those smokers with the lowest levels are more likely to get tobacco-related cancer. Supplements help.
... decreased levels of vitamin D may predispose smokers to developing tobacco-related cancer.
These results show for the first time that the risk of tobacco-related cancers as a group is associated with lower concentrations of vitamin D. The data also indicate that tobacco smoke chemicals may influence vitamin D metabolism and function, while vitamin D may conversely modify the carcinogenicity of tobacco smoke chemicals. If further research confirms this, it would be consistent with previous studies demonstrating the anti-tumorigenic effects of vitamin D derivatives, as well as the correlation of vitamin D deficiency with favorable cancer-forming conditions and increased susceptibility to tobacco smoke carcinogens. Interestingly, though, low vitamin D levels were not connected with risk of other cancer types.
New research showed that a supplement of 400 IU/day was insufficient to raise vitamin D blood deficient levels in healthy adults, but 2,000 IU/day was sufficient. They also found that sufficient vitamin D blood levels activated a wide range of genes associated with preventing "cancer, autoimmune diseases, infectious diseases, type 2 diabetes and cardiovascular disease".
The study ... reveals for the first time that improvement in the vitamin D status of healthy adults significantly impacts genes involved with a number of biologic pathways associated with cancer, cardiovascular disease (CVD), infectious diseases and autoimmune diseases.
At the end of the pilot, the group that received 2000 IUs achieved a vitamin D status of 34 ng/mL, which is considered sufficient, while the group that received 400 IUs achieved an insufficient status of 25 ng/mL.
The results of the gene expression analysis indicated statistically significant alterations in the activity of 291 genes. Further analysis showed that the biologic functions associated with the 291 genes are related to 160 biologic pathways linked to cancer, autoimmune diseases, infectious diseases and CVD. [emphasis mine]
... researchers found vitamin D supplements can help obese children and teens control their blood-sugar levels, which may help them stave off the disease.
"By increasing vitamin D intake alone, we got a response that was nearly as powerful as what we have seen using a prescription drug," said Catherine Peterson, an associate professor of nutrition and exercise physiology at MU. "We saw a decrease in insulin levels, which means better glucose control, despite no changes in body weight, dietary intake or physical activity."
"What makes vitamin D insufficiency different in obese individuals is that they process vitamin D about half as efficiently as normal-weight people," Peterson said. "The vitamin gets stored in their fat tissues, which keeps it from being processed. This means obese individuals need to take in about twice as much vitamin D as their lean peers to maintain sufficient levels of vitamin D." [emphasis mine]
I've read that if you're taking more than 2000 IU of vitamin D/day you should get your blood level checked periodically.
I take 3000 IU/day and last time I had a blood test for vit D, it was in high normal range.