Your immune system’s most powerful ally

It seems every time I sit back down to my computer, another study pops up about the importance of vitamin D. Today, I’ll tell you about three recent studies that caught my eye. They all illustrate vitamin D’s incredible effect on the immune system.

In the first study, researchers looked at vitamin D and its effect on colon cancer risk. They matched 318 people with colon cancer against a control group of 624 men and women without colon cancer. All the participants had given blood samples in the 1990s, before the appearance of any cancer.

The researchers measured the vitamin D levels in these samples and found the higher the participants’ vitamin D blood levels at the outset, the less likely they were to develop colorectal tumors. Vitamin D, the authors suggest, interacts with the immune system to prevent the growth of this type of malignancy.

In a second study, researchers found that vitamin D prolongs survival time in people with metastasized colon cancer (cases in which the cancer has spread beyond the original site in the body).

For this study, researchers followed 1,430 people with metastatic colon cancer. The patients in the lowest fifth for vitamin D levels survived for an average of 25 months. By comparison, patients in the highest fifth for vitamin D levels survived for an average of 33 months That’s 33 percent longer. In addition, higher vitamin D delayed any progression of the cancer from 10 to 12 months.

These findings make perfect sense.

You see, malignant tumors contain other types of cells besides the actual cancer cells, including T-lymphocytes or T-cells. These immune cells influence how fast a tumor grows or spreads. They attack cancer cells, which they consider “foreign,” and can limit tumor growth. And research has shown that vitamin D is necessary to activate these T-cells.

In yet another recent study, researchers linked low vitamin D with poorer recovery after major surgery. For this study, researchers at Massachusetts General Hospital and Harvard Medical School measured vitamin D levels of patients admitted to the hospital’s surgical intensive care unit (ICU). They found that ICU patients with low vitamin D blood levels spent more time on artificial respiratory support. Evidence links mechanical ventilation itself with a number of negative health outcomes. So getting off those breathing machines is a critical goal in critical care–and vitamin D helps.

Of course, we already knew that low vitamin D aggravates asthma and Chronic Obstructive Pulmonary Disease (COPD). Conversely, we know that boosting vitamin D levels improves lung function.

So a lot may come back to vitamin D’s role in supporting immune system function. It appears this critical nutrient inhibits inflammation in the lungs, while boosting the immune system to defend against respiratory bacteria and viruses. Indeed, a balanced immune system decreases unhealthy inflammation, while increasing healthy immune response against microbes.

No simple-minded, single-function drug can do anything like that. All they do is put the system out of balance. They either boost the immune system artificially, which increases inflammation. Or they deaden it, which reduces inflammation, but leaves you vulnerable to infection (as with steroids).

It’s remarkable that vitamin D positively influences the body’s reaction to so many diseases–from cancer to lung diseases. And that something as simple as keeping up your vitamin D levels (as with daily supplementation) can translate into measurable and meaningful benefits–well beyond the high-cost, high-tech, and invasive modern medicine that we throw at these devastating diseases.

Unfortunately, the government-industrial-medical guidelines for vitamin D are so pathetically constrained by their focus only on bone health, just following the RDA for vitamin D simply won’t provide the benefits this nutrient is capable of conferring.

You really need to take 5,000 IU of vitamin D daily. Even better, combine it with the natural powerhouse astaxanthin. You can now take them together as an easy-to-use and easy-to-absorb liquid.

Subscribers to my Insiders’ Cures newsletter can learn more about the importance of vitamin D in the January 2015 issue by logging onto my website at If you’re not yet a subscriber, now is the perfect time to get started.

P.S. A quick reminder: If you come down with the flu this winter, you can safely take up to 20,000 IU of vitamin D per day just for the duration of the illness. This course will help your immune system fight the infection more effectively. And it will undoubtedly be a whole lot more effective than relying on the pathetic flu vaccine or Tamiflu drug treatment.


  1. “Plasma 25-hydroxyvitamin D and colorectal cancer risk according to tumour immunity status,” Gut; published online 1/15/2015
  2. “Vitamin D status and survival of metastatic colorectal cancer patients: Results from CALGB/SWOG 80405,” J Clin Oncol 2015; 33
  3. Plasma 25-Hydroxyvitamin D Levels at Initiation of Care and Duration of Mechanical Ventilation in Critically Ill Surgical Patients,” Journal of Parenteral and Enteral Nutrition, January 2015