- Global Canine Communication




The connection between sunlight, cancer, and vitamin D will truly "enlighten" you! Why genetic diseases and health problems plague both dogs and people.





by Barbara J. Andrews, AKC Hall Of Fame Master Breeder - November 2008


Cancer rates are spiraling out of control in dogs.  Bone and joint deformities plague breeders.  Every time you turn around there's a new genetic disease.  It is not because veterinary research is discovering new diseases - it is because our dogs are getting sicker!


PUPPIES IN HEALTHY SUNLIGHTWe may complain about puppy mills but those bitches breed easily, conceive regularly, and whelp big litters.  We can not say the same about pampered purebreds and you are about to learn why.


Stick with me through the reference stuff, I promise you this will be worth the read and it will change the way you think about your dog's health - and your own!  If you haven't read Part 1 - Into The Sunlight, you might want to do so before reading this as it gives you solid background on thyroid hormone and other glandular functions that affect canine reproduction.


All mammals require sunlight.  We must turn to nature to protect our health, starting with the sun. Avoidance of sunlight to prevent cancer is a serious misconception which, like low-fat diets that encourage people to eat chemical-laden fake food, has seriously bad effects on reproduction, growth, and the immune system.


We adversely affect our dog's health and reproductive ability by keeping them indoors, in fact, "house dogs" - our closest friends, are the most affected by sunlight deprivation.  Lack of sunlight prevents absorption of vitamin D but it doesn't stop there.


It is hard it is to get medical truth before the public.  Michael F. Holick, MD, PhD, professor of medicine and physiology at Boston University School of Medicine, and until 2000, chief of endocrinology, metabolism and nutrition,  was asked to resign because he advocated moderate exposure to sunlight, not total avoidance. In an effort to totally discredit Holick's research, the department chair issued this statement “Dr. Holick’s book is an embarrassment for this institution and an embarrassment for him."


Avoid the sun?  Dermatologists are well paid to warn us about sunlight and ultraviolet light, scaring us to death with fears of melanoma, which of course, creates a huge demand for sunscreen - and cancer screenings.


Cancer is on the rise in dogs as well as humans. Even as we are warned about sunlight and skin cancer, the American Cancer Society states "We do not yet know exactly what causes melanoma …”  If you read my magazine columns, you are aware of the link between “manufactured” food (laced with chemicals and preservatives) and serious health problems, including cancer. What we now know is that vitamin D may also help prevent a variety of cancers! Could that explain the higher cancer rate among pampered pets and show dogs? Could it be that they spend more time indoors than the street mutt or hunting dog?


With over 3,500 PubMed articles on the topic, the National Institute of Health has stated that "laboratory, animal, and epidemiologic evidence suggest that vitamin D may be protective against some cancers” and subsequent dietary surveys associated "a higher calcium and vitamin D intake with a lower incidence of colon cancer." Vitamin D from natural sunlight may also help protect against prostate cancer, increasingly common in dogs.  In fact, so much so that a National Pet Press article details how dogs were used in new prostate cancer research human studies.


Dr. Holick has over 200 PubMed articles on the topic of vitamin D, relating it to the prevention of cancers, type 1 diabetes, heart disease, and osteoporosis." Even so, sunlight's beneficial biological effect seems to have been lost to modern medicine and those who keep animals in artificial conditions.


Meet the Editor and Author Barbara J. "BJ" AndrewsI have written about light deprivation many times and okay, most of you were bored to death but a few actually said that you don’t wear sunglasses as much, or you quit drawing the drapes on your house dogs during the day, or like a couple of northerners reported, you’re using those natural spectrum light bulbs in the long winter months.  And predictably, some have said bitches they were about to place in pet homes, suddenly began to reproduce!  No kidding...


So here’s a personal but interesting example that I hope will stick in your mind. We bred Bengal cats until a doctor said Bill was allergic to cats. I flew to California and had the honor of spending a few days with Jean Mills, the developer of the hybrid Asian Leopard/domestic cat. When my f2 female would not “call” for a mate, Jean said to put a halogen light down low so it would shine into the cat’s eyes as she moved about the enclosure. Huh? She explained that the light would stimulate her hormones. Even though we had built an elaborate outside cattery, Jean said the daylight was different in NC than in Southern California and the move had thrown her off cycle. Oooo-kay…… I did as she said, the cat quickly came in season, and I added that to my health notes.  I hope you are doing likewise!


About a year later, another breeder remarked that cats can not be kept under artificial light, that they “go crazy” and will not reproduce or fail to ovulate. She said that fluorescent lights were the absolute worst. I looked up at the brand new fluorescent lights over my work center and thought about how grumpy I had become. I reflected on the many hours I had previously spent outside; training, bathing and grooming my dogs and how since starting the Akita book, I had been glued to a computer screen. Interested but skeptical, I checked out a pile of books and learned how to research online. Three days later, I had those lights removed, ordered an Ott Light, picked up a leash and headed for the sunshine!


LET THE SUNLIGHT IN!So fling open the curtains, sunlight is no harder on the furniture than a bunch of dogs. Run the kennel dogs off those comfy beds and out of the air conditioning. If you’re in the blazing south, arrange your schedule so the dogs get outside in the early morning and late afternoon. Put nursing puppies outside, let them get dirty, dig holes, and eat grubs but above all, let them soak up the sunshine.


Straight legs. Strong bodies. Reduced cancer risk. Healthy reproduction and ovulation. Those are your tangible rewards.  This is not just dog medicine. Try it for yourself, especially if you work nights and sleep days. We could give you statistics on night workers but I don’t want to scare you.  Besides, TheDogPlace is for dogs.... and owners, and those who care enough to research!


Click here if you missed part 1:



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