How the sunshine vitamin fights cancer

The time to act is now.

If you're like most people, you're almost certainly low in vitamin D. But if you wait until you're sick to boost your levels, you may have waited too long -- because the sunshine vitamin can help fight diseases in the earliest stages or even make sure you never get them in the first place.

And a perfect case in point is cancer.

New research confirms that vitamin D could improve your health, increase the likelihood of remission and boost your odds of survival, adding years to your life -- but only if you already have high levels of it when you're diagnosed.

For every 10 nmol/L bump in blood levels of D at the time of diagnosis, the survival rate jumps by 4 percent, according to the analysis of data from 25 studies involving a combined 17,332 cancer patients.

In particular, high D levels may help you to survive both colorectal cancer and lymphoma. And if you have breast cancer or lymphoma, high D levels at the time of diagnosis will increase your disease-free survival rates.

The researchers say that maybe people with higher D levels are simply healthier to begin with, but I'm not buying that.

Vitamin D can fight cancer at the critical early stages of the disease in several different ways.

When tumors form, they establish their own blood vessel networks. Once in place, the tumor has everything it needs to keep growing.

It's a process called apoptosis, and it takes place long before most cancers are even diagnosed -- but vitamin D can disrupt that process, making it harder for the tumor to establish itself.

As a result, it grows more slowly and increases the odds that it'll be found before it establishes itself, when it's far easier to treat, or never even gets a chance to take root at all.

There's also evidence D can fight cancer on a genetic level, switching off certain signals so tumors stop growing -- and, again, the key here is in getting to the disease early on.

It's so effective that I bet many people have successfully fought off cancers they never even knew they had -- and not just colorectal cancer, breast cancer and lymphoma.

A second new study, for example, looks at prostate cancer. And if you have low D levels when you're diagnosed with the disease, you face a higher Gleason grade and more advanced tumor stage -- both of which mean the cancer is more aggressive and potentially deadlier.

And in African-American men, low D levels will even increase the risk of a prostate cancer diagnosis in the first place.

Your body makes D from sun, which is why people who live in nations close to the equator usually have much higher D levels (and much lower rates of some cancers and other diseases). But since sun exposure can also increase the risk of skin cancer, it's not always the best way to get it.

That's why I recommend a supplement.

The right amount for you will depend on your health, your skin tone, where you live and more, but nearly everyone needs between 2,000 IUs and 5,000 IUs per day.

Look for a quality D3 supplement from a maker you trust.