Studies have shown that deficiency in Vitamin D may be connected to prevalence of cancer in both humans and dogs. In 2008, the Journal of Cell Biology published research that found “vitamin D can adjust almost everything in the cancer cell, from its genetic messaging to its cytoskeleton. It can switch genes on and off, and it can reduce cell division, and it can calm the cancer cells so that they settle rather than spread. It seems vitamin D can actually return a cancer cell to a normal and healthy state. One pathway seems to control everything”.
Other recent research found that some 75% of dogs don’t have enough vitamin D. Unlike us, dogs get only minute amounts of Vitamin D from the sun and need to get it from their food. There are two types of Vitamin D, D2 and D3. D3 is the most useful for dogs and usually comes from fatty meats and liver. It is also possible to provide by supplementation such as cod liver oil.
Too much vitamin D can cause toxicity and death (usually in the form of kidney disease and failure) so it is important to be mindful of dosage levels. While it’s apparently difficult to test for vitamin D a 2014 study found that dogs should have vitamin D levels in their blood of 100-120 ng/mL. An active 15kg dog should have between 125 and 750 IU of vitamin D daily.
Nutrition delivered via the diet is always preferable over supplementation if possible, and always avoid synthetic vitamins. To ensure appropriate levels of vitamin D try the following:
- Feed your dog grass fed (and grass finished!), pastured animals. They’ll naturally have more vitamin D (and other nutrients) than animals raised indoors.
- Feed organic (or at least chemical and hormone free) meat whenever you can, especially organ meats. They’ll be less likely to be consuming foods with glyphosate and other nutrient robbing ingredients.
- Avoid commercial foods with synthetic vitamin D. If it says vitamin D on the label, it’s not vitamin D … it’s an artificial, chemical isolate and won’t behave the same way (and can cause harm if there’s too much).
- Supplement your dog’s diet with cod liver oil or similar.
REFERENCES AND FURTHER READING:
- http://www.canceractive.com/cancer-active-page-link.aspx?n=509
- http://articles.mercola.com/sites/articles/archive/2013/05/12/vitamin-d-may-prevent-breast-cancer.aspx
- http://www.dogsnaturallymagazine.com/new-study-shows-dogs-with-low-vitamin-d-are-at-risk-for-cancer/
- http://jcb.rupress.org/content/183/4/697.abstract
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4579370/
- https://www.ncbi.nlm.nih.gov/pubmed/25041357