Walnuts Slow Prostate Tumors

walnuts, prostate cancerWalnut consumption slows the growth of prostate cancer in mice, and has beneficial effects on multiple genes related to the control of tumor growth and metabolism, researchers have found.

A study shows that when mice with prostate tumors consume the equivalent of an amount of walnuts that could easily be eaten by a man, tumor growth is controlled.

Prostate cancer affects one in six American men. It is one in which environmental factors, especially diet, play an important role.

Numerous clinical studies have demonstrated that eating walnuts -- rich in omega-3 polyunsaturated fats, antioxidants and other plant chemicals -- decreases the risk of cardiovascular disease.

Dr. Mercola's Comments:

According to the latest statistics from the American Cancer Society, prostate cancer claimed an estimated 27,360 American men in 2009, and about 192,280 new cases were diagnosed.

Aside from skin cancer, prostate cancer is the most common cancer in American men. It’s also the second leading cause of cancer death, behind lung cancer.

About one in six men will be diagnosed with prostate cancer during their lifetime.

Most cases of prostate cancer do not occur until after men turn 50, but in recent years there has been a steady rise in the percentage of men in their 30s and 40s with both prostate problems and prostate cancer, primarily as a result of poor diet and increasing environmental pollution.

Unfortunately, recent investigations have discovered serious flaws with the PSA test used to diagnose prostate cancer. Researchers are also questioning the conventional treatments, which include surgical removal of the prostate gland and radiotherapy, as they may not be necessary for most men.

The PSA Test for Prostate Cancer is Deceptive

Six years ago, Stanford University News reported:

“The most commonly used screening tool for detecting prostate cancer – the PSA test – is virtually worthless for predicting men’s risk of contracting the disease, medical school researchers have determined.

Stanford scientists studied prostate tissues collected in the 20 years since a high PSA test result became the standard for prostate removal. They concluded that as a screen, the test now indicates nothing more than the size of the prostate gland.” [Emphasis mine]

Since then, PSA testing has become increasingly scrutinized, and most agree that PSA testing is unreliable at best, and useless at worst for accurately diagnosing prostate cancer. Many now agree that routine PSA blood tests often lead to over-diagnosis of prostate cancer, resulting in unnecessary treatments.

According to the American Cancer Society, “There can be different reasons for an elevated PSA level, including prostate cancer, benign prostate enlargement, inflammation, infection, age, and race,” all factors that make PSA test results confusing, leading to potential for unnecessary treatment and suffering when tests are elevated.

Complications of ill advised prostate cancer treatments include urinary incontinence and erectile dysfunction. Both of these conditions are difficult to reverse and can significantly decrease your quality of life.

Walnuts to the Rescue?

The fact that there seems to be almost no real safe and effective conventional option for diagnosis and treatment of prostate cancer can be depressing.

However, first I would encourage anyone facing this diagnosis to keep an optimistic attitude. After all, according the American Cancer Society the 5-year relative survival rate of all men with prostate cancer is, remarkably, 100 percent, and the relative survival rate at 10 years is 91 percent.

And secondly, I’d remind you to take a close look at some of the safest cancer-prevention and treatment support available, namely nutrition!

The article above discusses the potential benefits of walnuts, and as you will learn in a moment, there are also other nutritional therapies that may be more or less ESSENTIAL for successful avoidance and/or treatment of prostate cancer.

But first – walnuts!

According to Paul Davis, a nutritionist in the Department of Nutrition and a researcher with the UC Davis Cancer Center, the take-home message of his study is that heart-healthy food such as walnuts appear to be beneficial for your prostate as well.

Using mice that are genetically programmed to develop prostate cancer, he was able to show that walnuts had a significant impact on disease outcome. The mice that ate the human equivalent of 2.4 ounces of whole walnuts for 18 weeks had significantly smaller and slower-growing prostate tumors compared to the control group that consumed the same amount of fat but from other sources.

Overall the whole walnut diet reduced prostate cancer growth by 30 to 40 percent.

Using innovative gene technology, they were also able to detect that walnuts had specific effects on several genes that control tumor growth and metabolism.

Walnuts are good sources of omega-3 fats, natural phytosterols and antioxidants that can help reduce not only the risk of prostate cancer, but breast cancer as well.

According to another study on mice published last year, the human equivalent of just two handfuls of walnuts a day cut the breast cancer risk in half, and slowed tumor growth by 50 percent as well.

Considering the fact that walnuts are a healthy WHOLE FOOD, I see no reason not to incorporate some into your daily diet, whether as a preventive measure or as nutritional support if you’ve already been diagnosed with cancer.

One of the Most Potent Cancer Fighters – Vitamin D!

One specific treatment for prostate cancer that has been brought to the research forefront is vitamin D from sunshine exposure.

According to a study published last year, men with higher levels of vitamin D in their blood were seven times LESS likely to die from prostate cancer than those with lower amounts.

Vitamin D’s impact on your cancer risk is becoming increasingly well-documented.

There are in fact more than 800 scientific studies confirming the link between vitamin D deficiency and multiple types of cancers, including prostate cancer.

One groundbreaking study in particular discovered that correcting vitamin D deficiencies through appropriate sunshine exposure could prevent 600,000 cases of colorectal- and breast cancer each year, world-wide.

Personally, I believe one of the most powerful ways you can improve your health status is by optimizing your vitamin D levels. For more information on how to do this, please review this previous article. Overall, getting a safe amount of sun exposure on a regular basis, or taking an oral vitamin D3 supplement could reduce your risk of all cancers by at least half!

I can’t think of any other prevention strategy that can beat it.

Vitamin D has a protective effect against cancer in several ways, including:

  • Increasing the self-destruction of mutated cells (which, if allowed to replicate, could lead to cancer)
  • Reducing the spread and reproduction of cancer cells
  • Causing cells to become differentiated (cancer cells often lack differentiation)
  • Reducing the growth of new blood vessels from pre-existing ones, which is a step in the transition of dormant tumors turning cancerous

And for those who already have cancer, I believe it is virtually criminal malpractice, or at least gross medical negligence, to not optimize vitamin D levels when treating someone with this disease. According to vitamin D expert Dr. William Grant:

“From a scientific point of view, vitamin D reduces the risk of developing many types of cancer and increases survival once cancer reaches the detectable stage.”

Another “Forgotten Vitamin” that May Be Crucial for Cancer Reduction and Health

Vitamin K2 has also been found to offer significant protection against prostate cancer. One 2008 study by the European Prospective Investigation into Cancer and Nutrition (EPIC) found that increased intake of vitamin K2 may reduce your risk of prostate cancer by 35 percent.

Interestingly, the potential benefits of vitamin K2 were most pronounced for advanced prostate cancer.

Vitamin K has also been found beneficial in the fight against other cancers, including liver, colon, stomach, nasopharynx, and oral cancer, and some studies have even suggested vitamin K may be used therapeutically in the treatment of patients with lung cancer, liver cancer, and leukemia.

Vitamin K is vital in heart disease prevention as well, because it helps prevent hardening of your arteries – a common risk factor in coronary artery disease and heart failure.

Other beneficial effects of vitamin K include:

  • Helpful against Alzheimer’s disease
  • Topical vitamin K may help to reduce bruising
  • May have antioxidant properties
  • Strengthens bone (some studies have actually shown vitamin K to be equivalent to Fosamax-type osteoporosis drugs)
  • Improves skin

It is such an important vitamin that, although I don’t typically recommend adding extra supplements to your diet, vitamin K is one of the few supplements you should seriously consider because many people don’t get nearly enough of it on a daily basis through the foods they eat.

Although the exact dosing is yet to be determined, one vitamin K expert, Dr. Cees Vermeer, recommends between 45 mcg and 185 mcg daily for adults. You must use caution on the higher doses if you take anticoagulants, but if you are generally healthy and not on these types of medications, I suggest 100 mcg daily.

It is quite likely that doses of several times that amount are safe for the average person, but we just lack the research to confirm it at this time.

Please note that if you’ve experienced stroke, cardiac arrest, or are prone to blood clotting, do not take vitamin K without consulting your physician first.

Another important note is that vitamin K is a fat-soluble vitamin, which means that dietary fat is necessary for its absorption.

One easy way to do this is to mix liquid vitamin K drops with a high quality, animal-based omega-3 source like krill oil. This will ensure that the vitamin K is well-absorbed by your body. Alternatively, you could add it to any other food that contains healthy fat.

Additional Dietary Recommendations for Prostate Cancer Prevention

Also keep in mind that your diet can either help or hinder cancer development or progression. Eating higher amounts of vegetables and fruit, and avoiding high energy intake, excessive meat, and excessive dairy products and calcium may be helpful for preventing prostate cancer, and in treating patients already diagnosed with it.

One 2009 study identified the following foods as being particularly beneficial against prostate cancer:

  • Tomatoes
  • Cauliflower
  • Broccoli
  • Green tea
  • Vitamin E
  • Alkalinize your system with loads of raw foods 

Consumption of highly processed or charcoaled meats, dairy products, and fats correlated with an increased risk for prostate cancer and should therefore be avoided.

For a list of 14 additional guidelines and strategies to help avoid and treat both prostate- and breast cancer, please see this previous article.

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