In Davis's experiment, the mice eating the human equivalent of 2.4 ounces of whole walnuts daily for 18 weeks had significantly smaller and slower growing prostate tumors than did the control group eating equivalent fats from other sources.
The whole walnut diet slashed prostate cancer growth by 30-40%.2
The study also established that walnuts affected multiple genes which control tumor growth. And walnuts aren't the only nut with healthy benefit. . .
Nuts may be that rare thing — something that's
fun to eat AND good for you
Portable, long shelf life, nutritious, no preparation needed.
One of the most convenient and nutritious snack foods available. Yet nuts get a bad rap for being "too high-fat".
But placing all the focus on their high fat level is missing the big picture. Nuts can be an important part of a low-carb diet. And after many years of hearing the arguments fly back and forth, and doing some experimenting on myself, I've decided carbs are the main enemy, not fats.
It was the cancer connection that was the last straw for me. Refined carbohydrates have a clear role in promoting cancer — not to mention diabetes and heart disease. And nuts are a great way of getting off carbs.
Nuts are a rich storehouse of omega-3 fatty acids and flavonoid antioxidants (carotenes, quercetin, resveratrol, and lutein) — with the added benefit of fighting inflammation. Nuts reduce your risk of:
- Various cancers
- High blood pressure, coronary artery disease
- Strokes
- Arthritis
- Alzheimer's, schizophrenia, and depression.
Nuts have mineral power too, manganese, potassium, calcium, iron, magnesium, zinc, and selenium.
Manganese helps you produce the enzyme superoxide dismutase, a powerful free radical scavenger. Potassium helps control heart rate and blood pressure. And your body needs copper and iron to produce red blood cells.
What's more, nuts are a good source of B-complex vitamins, critical for energy and well-being.
Lastly, they provide high levels of vitamin E — a powerful lipid-soluble free radical scavenger.
Despite the warnings about the "high fat" content of nuts, I couldn't find evidence showing that eating nuts causes weight gain. In fact, replacing pastas and breads with a handful of nuts may control insulin resistance and help you lose weight.
Nuts are rich in this known cancer-fighter
Selenium shows great promise as a cancer preventive. Many studies show it's an effective tool against breast, esophageal, stomach, prostate, liver and bladder cancers. And it's an especially strong free radical scavenger that works synergistically with vitamins C, E and beta-carotene.
A 1996 study by Dr. Larry Clark showed a staggering 42% cancer rate reduction in those who took 200 micrograms of selenium daily for seven years, versus the placebo group. And in the selenium group, death rates were half that of the placebo group. Best results were for prostate, colorectal, and lung cancers.
Jean Carper, in Miracle Cures, called Dr. Clark's findings an "unprecedented cancer intervention study" that "bumped up the respectability of using supplements against cancer several notches."
Many foods contain selenium. But the bioavailable amount is heavily dependent on how selenium-rich the soil is. Soils rich in volcanic ash or in sediment deposited by sea water boast a higher selenium content than do other types of soil.
In the long run, your cancer risk may be determined by selenium levels where you live (assuming you eat locally grown food and don't take a selenium supplement). One theory for why cancer rates are so high in Linxian, China, dubbed "the world capital of cancer", is that the soil is woefully deficient in selenium and zinc.
It's been suggested that one reason American men are five times more likely to die from prostate cancer than Japanese men is that in general, "the Asian diet contains four times the amount of selenium as the average American diet."
What does selenium do? It activates an enzyme called glutathione peroxidase, which scavenges free radicals. Test tube studies show this enzyme inhibits tumor growth and regulates the natural life span of cells — ensuring they die when they're supposed to, instead of turning "immortal".
What else does selenium do?
- Converts hydrogen peroxide to water (preventing lipid peroxidation)
- Acts as an immune stimulant
- Produces antibodies
- Maintains a healthy heart and liver
Dr. Andrew Weil suggests this simple way to bump up your selenium levels,
Eat Brazil nuts!
Just one shelled Brazil nut — grown in central Brazil's selenium rich soil — gives you 120 micrograms of this mineral, getting you more than half way to your daily target of 200 micrograms.3
A staple in the Brazilian diet, these nuts — though high in fat and calories — actually reduce LDL cholesterol (the bad stuff), raise HDL (good cholesterol), and prevent cardiovascular disease and stroke. They're high in vitamin E, the B-vitamins, and minerals. Remember, selenium is more powerful when combined with vitamin E.
Selenium is especially important for those with prostate cancer.4
Like many nuts, Brazil nuts can cause allergic reactions in sensitive people, such as itchy mouth, wheezing, tight throat, hives, and even severe anaphylactic reaction. If you experience any symptoms after eating nuts, this issue's health tip is not for you. Consider taking a selenium supplement instead.
Excessive selenium levels may create toxicity. But since most people are deficient, that's a small concern.
What other specific kinds of nuts offer big health benefits? Check these out. Maybe you'll find a new excuse to eat your favorites.
Double the antioxidants of other nuts
You might want to eat a handful of walnuts every day to get the benefit of their potent antioxidant effects.
They deliver a near perfect balance of vitamins, minerals, and fiber — and also boast healthful oleic acid and omega-3 fats which lower deadly artery-clogging LDL cholesterol. Making walnuts part of your daily diet can help ward off cardiovascular disease and cancer.
Dr. Joseph Vinson compared walnuts to nine other nut species high in antioxidants — and found walnut's antioxidants were 2 to 15 times more powerful than vitamin E, doing more for your health than peanuts, almonds, pecans or pistachios.
His analysis also found that eating walnuts in their raw and natural form provides higher nutrient levels, because heating and roasting degrade its antioxidants.
Walnut's other benefits?
- Lower LDL and higher HDL5
- Rich source of vitamin E — a powerful lipid soluble free radical scavenger6
- Packed with B-complex, magnesium, zinc, calcium, iron, copper, selenium7
- Contain melatonin, ellagic acid, vitamin E, carotenoids, and poly-phenolic compounds8
- Fights cancer, inflammation, aging, heart attacks, stroke and neurological disease9
Walnuts may be particularly helpful for breast10 and prostate11 cancers. As mentioned at the beginning of this article, a diet rich in walnuts resulted in a 30 to 40 percent reduction in prostate cancer growth in mice.
And then there's:
The raw nut that's not really raw
Almonds have long been a symbol for wellness and health.
Like other nuts, they offer healthy levels of fats, vitamins, minerals, phyto-nutrients, vitamin E, B-complex vitamins, selenium, and other antioxidants. They're also gluten free and part of a Mediterranean diet.
As you might expect, they're protective against coronary disease, cancer, diabetes, Alzheimer's, and more.12
Almonds' high levels of folic acid are believed to help lower homocysteine levels, cutting your risk of arterial buildup. One study showed that just 3 ounces per day lowered cholesterol by 14%.13
Their high fiber improves digestive function, reduces constipation, and lowers colorectal cancer risk.
Almonds help control your blood sugar levels, too, making this snack beneficial for diabetics, the insulin resistant, and the overweight. Plus, munching on a few almonds after work may make you less inclined to overeat at dinnertime.
As with any food, once you heat it, you denature the proteins and make it less bioavailable. But unfortunately, the U.S. government has taken that risk to a whole new level.
Warning — U.S. 'raw' almonds are NOT raw!
In 2001 and 2004, there were small salmonella outbreaks associated with just two specific almond growers. The U.S. Department of Agriculture seized the excuse to mandate pasteurization of U.S. almonds. They make no exceptions for organic almonds, especially after organic almond growers opposed to pasteurization lost a lawsuit on this issue in 2009. All domestically grown almonds must be pasteurized, post 2007.
Not to worry, though. Richard Waycott, CEO of the Almond Growers of California reassures us that they no longer use heat or radiation to pasteurize.
Instead they use propylene oxide!
Per Wikipedia, propylene oxide was once used as a racing fuel, but that practice is now prohibited under the National Hot Rod Association rules for safety reasons. (Ironic, isn't it?) It was used in glow fuel for model aircraft and surface vehicles, typically as an additive in small percentages of around 2% to the typical methanol, nitromethane, and oil mix. And, it's also used in thermobaric weapons.
Warnings from the EPA's Hazard Summary sheet on propylene oxide:
- Short-term exposure causes eye and respiratory tract irritation.
- Skin contact, even diluted, causes irritation and necrosis in humans.
- Depresses the central nervous system (CNS) in humans.
- Causes tumors near the site of administration in rodents.
- Classified as a probable human carcinogen (Class 2B) by the EPA.
But yet, it's 'safe' for fumigating your almonds?
I can't recommend organically grown almonds.
You might be able to get true organic almonds by taking advantage of a loophole or two. You'd need to buy from a retailer or mail order supplier who sells imported almonds, or who buys from a farmer in amounts less than 100 pounds. Of course, this suggests that salmonella was never really the issue — but that's another whole story.
The rest of the nuts
In the space I've got, I can't go into detail on every conceivable nut. But certainly pecans and cashews rank high in popularity and deserve a mention here.
They both possess many of the qualities of other nuts.
Cashews contain small amounts of Zeaxanthin, a flavonoid antioxidant that can be absorbed into your eyes, and may be protective against age related macular degeneration. Cashews also contain healthy levels of selenium.
Pecans contain ellagic acid, which inhibits the DNA binding of certain carcinogens, protecting you from cancer.14 And they're a rich source of vitamin E.
Lastly, there's the peanut, which isn't actually a nut at all, but a legume. Peanuts boast many of the same nutrients as true nuts, including antioxidants. They protect from cancer (particularly stomach cancer), heart disease, degenerative nerve diseases, Alzheimer's, and more.
However, besides being a common and sometimes serious allergen, peanuts are susceptible to fungal (read: mold) infection from aflatoxin — a very powerful and dangerous toxin known to cause cancer and liver cirrhosis. Roasting helps reduce its toxic load, but other nuts may give you more health benefits with less risk.
The bottom line on nuts
Provided you don't have nut allergies, they provide many health-protective benefits not easily achievable by replacement with other foods. I eat raw nuts, not roasted and salted, and I buy organic whenever possible.
Interesting question: Are pesticides, herbicides and fertilizers actually used much in growing nuts? It doesn't seem to me that nuts would be subject to pests since they're protected by a shell. And they're grown on a tree, so why would a grower need herbicides? A lot of smart people read this newsletter, so maybe someone out there can answer this question. If my guess is right, it may not matter much if you eat nuts that aren't organic.
Nuts are a great option for wholesome gifts during the holidays and any time — much better than candy and cookies. And you do a great favor to diabetics and the insulin resistant to provide nuts at parties and family get-togethers.
