By Dr. Mercola

Carole Baggerly is the founder director of GrassrootsHealth. Her organization’s mission is to increase awareness about vitamin D and the crucial role it plays in many aspects of your health.

Carole is on the cutting edge of vitamin D research, with her finger on the pulse of some of the world’s leading vitamin D scientists.

Prior to this focus, Carole’s educational background included physics and mathematics, and she owned and managed an aerospace business. However, her passion for vitamin D arose from a more personal experience. She is a breast cancer survivor and attributes a large portion of her healing to vitamin D.

Her particular combination of managerial and executive skills, education in the sciences and personal health battles make her uniquely qualified to get this critical information into the hands of the public.

I first interviewed Carole in 2011. In this second interview, Carole discusses what the latest science says about how vitamin D prevents and slows multiple forms of cancer, and why it’s so important to have your serum levels tested on a regular basis.

In fact, optimizing your vitamin D levels may help you prevent more than 16 different types of cancer including pancreatic, lung, ovarian, breast, prostate, and skin cancers.

Modest Vitamin D Levels May Decrease Your Risk of ALL Cancer by 77 Percent

Vitamin D has shown preventative benefits for many diseases, including heart disease and diabetes, and can even reduce chronic pain¹. But when it comes to cancer, vitamin D is its worst enemy! Theories linking vitamin D deficiency to cancer have been tested and confirmed in more than 200 epidemiological studies, and understanding of its physiological basis stems from more than 2,500 laboratory studies.

One particularly noteworthy study was completed by Joan Lappe and Robert Heaney in 2007². A group of menopausal women were given enough vitamin D to raise their serum levels to 40 ng/ml.

These women experienced a 77 percent reduction in the incidence of all cancers, across the board, after just four years³. The remarkable thing is, 40 ng/ml is a relatively modest level. The latest information suggests the serum level “sweet spot” for vitamin D is 50 to 70 ng/ml. To have such stunning findings at just 40 ng/ml underscores just how powerful and important vitamin D is to your body’s optimal functioning.

Could Breast Cancer Be 90 Percent Preventable, Just with Vitamin D?

Vitamin D has powerful effects when it comes to breast cancer, to the degree that breast cancer is being described as a “vitamin D deficiency syndrome.” Of course, other lifestyle factors are also important in preventing cancer, such as nutrition, exercise, sleep, and managing stress. However, vitamin D’s critical importance seems to grow with every emerging study.

Carole believes that 90 percent of ordinary breast cancer is related to vitamin D deficiency — which is 100 percent preventable!

This is absolutely a profoundly important statement. As breast cancer is the most common cancer in women, this has massive implications for women’s health. For more information about breast cancer, I invite you to watch my informational video on the subject. Please be aware though that she is referring to more common types of breast cancer as opposed to inflammatory breast cancer and some of the other unique forms.

Vitamin D Can Make Breast Cancer Cells Fall Apart

Dr. Cedric F. Garland of the University of California's San Diego Moores Cancer Center is the epidemiologist who has connected the dots between Vitamin D deficiency and cancer. According to Garland, in nearly all forms of breast cancer, vitamin D affects the structure of your epithelial cells. These cells are held together by a glue-like substance called E-cadherin, which provides structure to the cell. E-cadherin is made up of mostly vitamin D and calcium.

If you don’t have adequate vitamin D, that structure comes apart and those cells do what they are programmed to do in order to survive — they go forth and multiply. If this growth process (cell proliferation) gets out of control, you may end up with cancer.

If you have breast cancer in progress, the addition of vitamin D can help stop cancer cells in their tracks by replenishing E-cadherin. Once cancer growth is slowed, your immune system can begin to get ahead of the cancer cells, because it doesn’t have to deal with gazillions of them. It’s just disposing of the “leftovers.” The theory above is Dr. Garland’s DINOMIT theory and has been substantiated by subsequent studies by other researchers.

Optimizing Vitamin D Reduces Your Risk of Preterm Birth by HALF

In addition to being a strong cancer preventive, if you are a pregnant woman, vitamin D has some important benefits for you and your baby. Unfortunately, an astounding 80 percent of pregnant women are vitamin D deficient, and you definitely do not want to be one of them.

Carol Wagner and Bruce Hollis studied the effects of vitamin D levels on pregnant women, with phenomenal results. The researchers gave 4,000 IUs of vitamin D to a group of pregnant women, lowering their incidence of preterm deliveries by a whopping 50 percent. These stellar results gave rise to a new prenatal program at GrassrootsHealth, called Protect Our Children Now, which you can learn about on their website.

Vitamin D is also known to improve a number of different problems of pregnancy, including reducing your risk of having a low birth weight baby and lowering your chances of C-section. If you’re pregnant and have good D3 levels, you are passing on important health protection to your newborn baby that will continue well after birth.

It’s ALL About Your Vitamin D Blood Level

The most important factor is your vitamin D serum level. It doesn’t matter how much time you spend in the sun, or how much vitamin D3 you take: if your serum level is low, then you’re at risk, plain and simple. And the only way to know your serum level is to test it. As of the present time, we don’t understand why people differ so widely in their serum responses to vitamin D supplementation. Until science figures this out, the only way to determine your serum level is by testing your blood on a regular basis.

Fortunately, all of the major labs have updated their vitamin D testing protocols, so it no longer matters which lab you use. It’s recommended you check your level every three to six months, because it takes at least three months for it to stabilize after a change in sun exposure or supplement dose.

The window you’re shooting for is 50 to 70ng/ml. More studies are needed to tease out the benefits of getting your serum level above 50, and 60, and 70 — in terms of what specific benefits occur at each increment. Above 20, you’re safe from rickets. Above 30, your gums will be healthy. Above 40, you receive great cancer benefits. But there may very well be reasons to push your level even higher — we just don’t have this information available yet. Science progresses slowly, and researchers are very cautious. For an interesting chart that shows disease prevention by serum vitamin D level, based on the research to date, visit this page on the GrassrootsHealth site.

It is Actually Difficult to Get Toxic 

The best way to optimize your vitamin D level is through sun exposure or a safe tanning bed as that virtually eliminates any risk of overdose. As a very general guide, you need to expose about 40 percent of your entire body to the sun for approximately 20 minutes between the hours of 10 am and 2 pm, when the sun is at its zenith. There appears to be no risk of vitamin D toxicity from ultraviolet B exposure.

If you’re using an oral supplement, recent studies suggest adults need about 8,000 IU’s of oral vitamin D3 per day in order to get serum levels above 40 ng/ml. However, remember that if you take oral vitamin D, you also need to boost your vitamin K2, either through your food choices or a supplement. Vitamin K2 deficiency is actually what produces the symptoms of vitamin D toxicity, which includes inappropriate calcification that can lead to hardening of your arteries. In general, however, taking vitamin D3 is very safe. Even the conservative Institute of Medicine has concluded that taking up to 10,000 IU per day poses no risk for adverse effects.

The ideal or optimal ratio between vitamin D and vitamin K2 has yet to be elucidated, so there’s little to go on in this regard. Dr. Kate Rheaume-Bleue, author of Vitamin K2 and the Calcium Paradox: How a Little Known Vitamin Could Save Your Life, suggests 150-200 micrograms of K2 per day will meet the vitamin K2 needs of the "average" healthy person, if you’re not taking a vitamin D supplement. Keep in mind that some of that can come from your diet, such as fermented vegetables. If you take a vitamin D supplement, you may need to increase your vitamin K2 some more.

Your health insurance may very well pay for vitamin D testing. If not, there is a wonderful program you can participate in through the mail, developed by GrassrootsHealth, called D*Action Project. For more information on how to participate, read on.

How Vitamin D Performance Testing Can Help Optimize Your Health

Additionally, a robust and growing body of research clearly shows that vitamin D is absolutely critical for good health and disease prevention. Vitamin D affects your DNA through vitamin D receptors (VDRs), which bind to specific locations of the human genome. Scientists have identified nearly 3,000 genes that are influenced by vitamin D levels, and vitamin D receptors have been found throughout the human body.

Is it any wonder then that no matter what disease or condition is investigated, vitamin D appears to play a crucial role? This is why I am so excited about the D*Action Project by GrassrootsHealth. It is showing how you can take action today on known science with a consensus of experts without waiting for institutional lethargy. It has shown how by combining the science of measurement (of vitamin D levels) with the personal choice of taking action and, the value of education about individual measures that one can truly be in charge of their own health.

In order to spread this health movement to more communities, the project needs your involvement. This is an ongoing campaign during the month of February, and will become an annual event.

To participate, simply purchase the D*Action Measurement Kit and follow the registration instructions included. (Please note that 100 percent of the proceeds from the kits go to fund the research project. I do not charge a single dime as a distributor of the test kits.)

As a participant, you agree to test your vitamin D levels twice a year during a five year program, and share your health status to demonstrate the public health impact of this nutrient. There is a $65 fee every 6 months for your sponsorship of the project, which includes a test kit to be used at home, and electronic reports on your ongoing progress. You will get a follow up email every six months reminding you "it's time for your next test and health survey."