Lead in Seafood and Wild Game

Most hunters may not be aware of the health risks related to consuming meat from animals shot with lead ammunition.

I’m often asked in lectures whether microwaves are safe. Not if you drop them on your foot! But, otherwise, it matters what you’re putting in them—sweet potatoes and broccoli, or hot pockets and pop tarts? Similarly, when I was exploring the safety of hot sauces in my video Flashback Friday: Lead Contamination in Hot Sauces, given their potential for lead contamination, I had a similar reaction: It matters what you’re putting them on.

When I think about toxic pollutants, the first thing I think of is the aquatic food chain. We know, for example, that giving people a seven-ounce portion of a fish high in mercury, like tuna or swordfish, just once a week, which is about a can and a half of tuna a week, can quadruple mercury levels in the blood within a few months. What about lead?

A dietary intervention with not one but five portions a week significantly increased blood concentrations of toxic metals, including lead. Even though “the background intake of lead was already disturbingly high,” the seafood intake “increased the intake of lead by approximately 25%.” From a public health perspective, it is important to recognize that the amount of seafood researchers used in the study “far exceed[ed] the intake of most populations.”

Lead can also bioaccumulate in other animals, but half of our dietary exposure to lead probably comes from plant foods. Animals shot with lead ammunition, though, may present a special case. I explore this in my video Lead Contamination in Fish and Game.

We know lead is toxic and banned from most household items in developed countries—except for lead ammunition, which “is now likely the greatest, largely unregulated source of lead that is knowingly discharged into the environment in the USA.” But, it is not just discharged into the environment. It’s also discharged into the meat itself. “People generally reject the idea of injecting toxic substances into food, except when it involves hunting wild game.”

Eighty percent of ground venison was found to contain lead, which isn’t surprising given the hundreds of metal fragments that end up in deer carcasses after being shot with standard lead-based rifle bullets—“an impossible number of fragments to pick out by hand, especially because some of these fragments are microscopic.”

As you can see at 2:23 in my video, researchers have shown using x-rays that during penetration, expanding lead core bullets typically release hundreds or thousands of fragments—or even millions or tens of millions of microscopic lead particles per gram. So, one serving could have a billion particles, though they are nanoparticles, extremely tiny, about the size of viruses. 

The only good lead, though, is no lead. Even very low levels of lead exposure can result in brain and nerve damage, yet most hunters may not be aware of health risks related to consuming meat from animals killed with lead ammunition.

Children may be at risk of losing IQ points, which could reduce their future prospects. “Often when I explain to hunters the risk associated with lead exposure, especially when considering their children,” writes a physicians, “their response is, ‘I have been hunting for years and I am fine.’ My response to them is, “but just imagine how smart you could have been.”

Bone broth is another issue, which I cover in Lead Contamination in Bone Broth.

I recently did a deep dive into lead if you’re interested in a comprehensive overview:

In health, 

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

Natural Dietary Treatments for Fibroids

The same diet that helps regulate hormones in women may also reduce exposure to endocrine-disrupting pollutants.

Fibroids are the most common benign tumors in women. They can grow to a foot in diameter and affect the majority of women before they hit menopause. Although fibroids tend to be asymptomatic, when symptoms do occur, they tend to manifest as heavy menstrual bleeding—so much so that women may get anemic and experience a lot of pain. So, what can women do? I discuss this in my video The Best Diet for Fibroids.

Up to half go into surgery and get their entire uterus removed. “Although hysterectomy is generally considered a safe operation, complications occur in a significant proportion of patients” and, obviously, you can’t have kids any more. The alternative is a variety of hormone-modulating drugs, which can shrink the fibroids and provide relief, but many of these drugs have significant side effects, like bone loss, so you really don’t want to be taking them for more than a few months. What’s the bottom line? “There is currently no evidence to support the routine use of medical treatment in women with uterine fibroids.” No wonder many women turn to “complementary and alternative treatments…including exercise, diet, herbs, and acupuncture.”

Women who exercise seven or more hours a week do seem to have lower risk of having fibroids than women who exercise less than around 20 minutes a day, but exercise has never been put to the test for treating fibroids. Likewise, to date, there isn’t a single randomized controlled trial of acupuncture for the treatment of fibroids to help guide us. 

In terms of herbs, there are two Asian herbal preparations that show promise—a five-herb combo called Guizhi Fuling and a Malaysian ten-herb formula that contains “secret ingredients” that must not be that secret since they’re just listed in the study, as you can see at 1:50 in my video—and they seemed to work as well as a leading drug. The problem is that traditional Asian herbal remedies may contain a few extra ingredients, like arsenic, mercury, and lead, which have been detected in most of the samples tested from Asian market and health food store shelves, and not just a little. Some, apparently, had really toxic amounts. So, these two Asian herbal preparations “may reduce fibroid size, but there is insufficient evidence to support the efficacy or safety of these treatments.” And, certainly, don’t try to apply caustic herbs internally, as this can lead to scarring, stenosis, and ulceration.

Well, what about diet? In one of the largest studies of diet and fibroids, fibroid tumors were “associated with beef and ham consumption, whereas high intake of green vegetables seems to have a protective effect.” The researchers figured that the “association between levels of estrogen, diet, and breast and endometrial [uterine lining] cancers also may help us understand” why. Indeed, “[f]or breast and endometrial cancers, a direct association with the frequency of consumption of meat and ham was observed…whereas protection was conferred by high intake of vegetables and fruits.” Thus, there may be these shared risk factors between estrogen-responsive malignant tumors, like breast cancer, and estrogen-responsive benign tumors, like fibroids.

We know the presence of fibroids seems to correlate with an increase in the amount of estrogens flowing through your body, for example, and that women eating vegetarian diets have significantly lower levels of excess estrogen. Researchers are using this knowledge to try to explain why there are lower rates of endometrial cancer—that is, lining-of-the-uterus cancer—and possibly breast cancer among vegetarian women, but it could also help explain the fibroid findings. “The incidence of breast cancer among vegetarian American women (Seventh Day Adventists) is 60 to 80 per cent of the incidence among American women in general, and the incidence among women in Africa and Asia is even lower.” Why might vegetarian women have lower estrogen levels? A famous study in the New England Journal of Medicine concluded that it was their “increased fecal output, which leads to increased fecal excretion of estrogen,” resulting in lower blood levels. Double the fecal output, in fact, as you can see at 4:07 in my video.

And, you can put it to the test. Maybe the same reason African-American women have more fibroids is the same reason they have worse breast cancer survival: too much estrogen in their bloodstream due to a less than optimal diet. So, researchers designed a study to see what would happen if they were switched to a more plant-based, higher fiber diet. Compared with the Caucasian women, the African-American women started out with much higher estrogen levels, again helping to explain their increased mortality from breast cancer. But, after they were put on a healthier diet, all of their levels came down, “suggest[ing] that a substantial reduction in breast cancer risk can be achieved” by adopting a diet centered around more whole plant foods. The same also appears to be true for fibroids, especially eating lots of cruciferous vegetables—broccoli, cabbage, and Chinese cabbage—as well as tomatoes and apples.

Women who underwent premature puberty, starting their periods before age 11, may also be at increased risk of fibroids later in life, and we know that higher childhood red meat intake is associated with earlier age of starting one’s period, though total protein and animal protein in general may contribute. For example, girls who eat meat tend to start their periods about six months earlier than vegetarian girls. Those who eat meat analogues like veggie burgers and veggie dogs start their periods nine months later on average, and a similar puberty normalizing influence was found with consumption of whole plants foods, such as beans. 

It could also be the endocrine-disrupting pollutants that build up the food chain. Researchers took samples of internal abdominal fat from women and found there appeared to be a correlation between the presence of fibroids with the levels of a number of PCBs in their fat. So, does that mean fish-eaters have higher risk of fibroids? Researchers did find a small increase in risk associated with the intake of long-chain omega-3 fats, mostly from “dark-meat fish consumption,” by which they meant fish like sardines and salmon. This could be because of “the endocrine-disrupting chemicals commonly shown in fish,” or it could just be a statistical fluke. It would be consistent with the increased risk seen among “sport-fish consumers.” 

Recognizing that diet and endocrine-disrupting persistent organic pollutants have been associated with a variety of gynecologic conditions, including fibroids, researchers looked at consumers of fish fished out of the Great Lakes and found a 20 percent increased risk for every ten years they had been eating the fish. In the most comprehensive study to date, researchers compared pollutant levels in fat samples from women with fibroids to fat liposuctioned out of women without fibroids. They didn’t just find higher levels of PCBs in fibroid sufferers, but also long-banned pesticides, like DDT and hexachlorocyclohexane, PAHs, which are polycyclic aromatic hydrocarbons formed when coal is burned, tobacco is smoked, and meat is grilled, as well as heavy metals, arsenic, cadmium, lead, and mercury. These levels correlated not only to fibroids, but also to seafood consumption or excess body fat. So, the researchers determined that “shedding excess weight and limiting seafood consumption would confer a protective effect” on fibroid tumor development by minimizing exposure to environmental pollutants as much as possible.

Okay, so a plant-based diet may be best, but is there a plant in particular that has been shown to be particularly powerful?

Plant-based compounds with disease-preventive properties, dietary phytochemicals are found in whole grains, fruits, vegetables, beans, split peas, chickpeas, and lentils, herbs, spices, nuts, and certain beverages. As I discuss in my video The Best Food for Fibroids, we know they can help regulate the initiation, promotion, and spread of cancerous tumors, so what about benign tumors like fibroids? Most anti-cancer drugs on the market now were originally derived from plants or plant products, so why not try to use plants to target the inflammation or blood supply of fibroids? Might fibroids be a consequence of chronic inflammation within the body? We know that women with fibroids are more likely to eat more beef and ham, and fewer fruits and green vegetables, but whole plant foods don’t just have anti-inflammatory effects but antioxidant effects as well. “If the generation of free radicals exceeds the protective effects of antioxidants, oxidative damage will occur,” which has been implicated in a variety of disease states, including gynecological conditions such as fibroids. 

If you collect fresh fibroids, as well as normal uterine tissue from hysterectomy surgeries, the fibroid cells have significantly fewer antioxidant enzymes, as you can see at 1:20 in my video, so might antioxidant-rich foods help? Well, if you drip some strawberries onto cells in a petri dish, you can apparently kill of some fibroid tumor cells, while leaving normal uterus cells alone. But, what good does that do us? That’s only relevant if we can show those strawberry compounds get absorbed through our gut and achieve high enough concentrations in uterine tissue. The same with curcumin, the component of the spice turmeric. One of its so-called “miraculous” properties is suppressing the growth of uterine fibroid cells, but, again, that was just in vitro. Yes, an inhibitory effect was found and at concentrations that don’t compromise the growth of normal, regular uterine tissue, but my patients are people, not petri dishes. 

It’s pretty neat to find out what happens to human fibroid cells as you drip higher and higher concentrations of green tea compounds on them in a test tube, as you can see for yourself at 2:19 in my video, but I care less about what happens in vitro or in mice, whether or not they have any clothes on—one study looked at “a nude mice model”—but there were no randomized, controlled clinical studies until 2013. 

Subjects were randomized to green tea extract or placebo for four months. In the placebo group, fibroid volume increased by 24 percent. That’s what fibroids do; they continue to grow. However, those randomized to the green tea group showed a reduction in total fibroid volume—and not just by a little. There was a dramatic decrease, shrinking by almost a third, which is a highly significant difference, as you can see at 3:02 in my video. Okay, but did the women feel any better? Yes, they experienced a dramatic decrease in symptom severity, as well. Month after month, nothing much happened in the placebo group, but those taking the pills that looked the same but happened to contain green tea compounds had consistent improvement and felt lessening symptoms, each month better than the last, as well as an improved health-related quality of life, month after month, that was significantly better than control. What’s more, their blood counts got better too. With all that continued excess blood loss every month, the blood levels kept decreasing in the placebo group, but they reversed in the green tea group. So, anemia also significantly improved, because average blood flow significantly diminished. And, all this—the fibroid shrinkage, less pain, better periods—was achieved with “no adverse effects.” 

So, not only were the results comparable to those for the drugs that are commonly used—again, without the side effects—but the results were also comparable to uterine artery embolization, where they try to cut the blood supply to the fibroid, which is great—unless they accidentally cut the blood supply to the rest of the uterus and cause uterine necrosis, one of many reported major complications. Others include death, not only of the fibroid, but also of the patient, along with other potential complications that may arise from accidentally clogging off non-target arteries. In my book, a side-effect-free solution as good as a more invasive procedure is potentially better than. The researchers conclude that green tea compounds show “promise as a safe and effective therapeutic agent for women with symptomatic UFs [uterine fibroids]. Such a simple, inexpensive, and orally administered therapy can improve women’s health globally.” 

Relatively safe doesn’t mean risk-free, however. Although there were no liver function abnormalities detected, this was a small study. If you give green tea extract pills to a thousand women for a year, like they did in the Minnesota Green Tea Trial for breast cancer, the livers in about 1 in 17 women started to get inflamed and a few became serious. Now, the dose they used in this study was twice that of the fibroid study and it’s not completely clear if the pills were the only cause, but, in general, we should try to avoid extracts and instead get nutrition from foods as grown—or at least from foods as grown that are then dunked in hot water, like green tea. 

The researchers had to use pills in this study, because they wanted it to be a double-blind study and it’s hard to create a placebo tea that looks, smells, and tastes like the real thing. I don’t think we should take green tea extract pills, though. We should drink green tea. The problem is that the dose the researchers used was about 11 cups a day, which would be a lot of caffeine. You could choose decaf, though, and it’s not outside the realm of possibility to drink a couple quarts of tea a day, especially if doing so may shrink your fibroids so much you can keep your uterus. But, for all we know, five cups of tea a day would work or maybe even three cups or one cup. No other dose has been tested, so we just don’t know. But, you can test it in your own life. If you have fibroids, it couldn’t hurt to add a few cups of green tea to your daily diet and see if you start feeling better.

And, for even more on fibroids, see Should Women with Fibroids Avoid Soy? and Talcum Powder and Fibroids.

For more on contaminated herbal products, see Get the Lead Out and Some Ayurvedic Medicine Worse Than Lead Paint Exposure.

I’ve got dozens and dozens of videos on the effects of diet on estrogens, such as:

In health, 

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations:

What’s Best for Eczema (Atopic Dermatitis): Coconut Oil vs. Mineral Oil vs. Vaseline

Natural topical remedies for eczema, including licorice root gel, St. John’s Wort cream, and emollients such as coconut oil, mineral oil, and petroleum jelly, are put to the test.

Despite the availability of drugs with proven efficacy for eczema, like topical steroids, many patients seek out natural alternatives. Which plant, then, should be used for which skin disease? In the case of eczema, two appeared to beat out placebo. One was licorice root. As you can see at 0:24 in my video Eczema Treatment with Coconut Oil vs. Mineral Oil vs. Vaseline, smearing on a placebo gel didn’t appear to help much with clearing redness or itchiness after one week or two weeks, but a 1 percent licorice gel and especially a 2 percent gel did seem to clear the symptoms in most patients. The researchers concluded that licorice extracts could be considered an effective eczema treatment agent.

The other successful trial was with a St. John’s wort cream, showing a reduction in eczema severity scores week by week superior to that of placebo, as you can see at 0:49 in my video. So, it works better than nothing, but does it work better than drugs? Better than the topical steroids? That we don’t know. Sometimes, the drugs don’t work on so-called recalcitrant atopic dermatitis, so researchers in Japan asked patients to drink four cups of oolong tea every day for a month. Most patients “showed marked to moderate improvement,” starting after one or two weeks, and then most remained better even five months after they stopped. The problem is there was no control group, so we don’t know how many would have gotten better on their own. But, since drinking tea is healthy anyway, why not give it a try? 

Let’s get back to topical treatments. As you can see at 1:43 in my video, a vitamin B12 cream showed better results than the same cream without vitamin B12. Most of the patients and doctors rated the results of the B12 cream as “good,” which was better than they scored the placebo cream. 

Regardless of what topical agent you use, steroid or otherwise, “first and foremost, it is essential that the skin barrier is protected and maintained with the use of emollients,” meaning moisturizers, ideally once or twice a day, especially right after showering, to lock in the moisture. Petroleum jelly, like Vaseline, is highly effective, but it “is greasy and can be messy,” so what about something like coconut oil, which is less greasy? It was found to improve skin dryness, though no better than mineral oil, which is cheaper. Is mineral oil safe, though?

Exposure to mineral oil was found to be associated with rheumatoid arthritis, but that was occupational exposure to industrial mineral oils, like hydraulic fluid. The same group of researchers subsequently found that cosmetic grade mineral oil did not seem to carry the same risk. In general, topically applied mineral oil shouldn’t present any health risk, but that doesn’t mean…you can safely inject it into your penis, as that “may have devastating cosmetic and sexual function consequences.” There is, however, evidently one good use for mineral oil on the penis, and that’s for “penile zipper entrapment.” Skin of the penis “is susceptible to entrapment in the zipper of careless young boys, particularly those who fail to wear undergarments. Understandably, this mishap provokes distress in the unfortunate victim, in his parents, and ultimately in the health care provider charged with the task of liberating the organ.” A recommended textbook approach is surgery, believe it or not, but if you simply dose liberally with some mineral oil, you can just slip the zipper off and “physical and psychologic trauma is minimized for all parties involved…”

But, just because mineral oil works as well as coconut oil for dry skin, doesn’t mean it works as well for eczema. Head-to-head topical virgin coconut oil works better than topical mineral oil at decreasing eczema severity, with twice as many children experiencing an excellent response after two months treatment. Thus, among pediatric patients with mild to moderate eczema, topical application of virgin coconut oil was superior to mineral oil, but what about compared to virgin olive oil? As you can see at 4:19 in my video, olive oil worked, dropping eczema severity, but coconut oil worked better. 

As I discussed previously in my video What about Coconuts, Coconut Milk, and Coconut Oil MCTs?, we know that coconut oil has a lot of saturated fat, so we don’t want to consume it, but the saturated fat isn’t absorbed into your skin unless you are a baby, when your skin is so thin that you can actually absorb saturated coconut fat into your bloodstream. But, in older children and adults, using coconut oil on your skin or hair is considered safe. 

What about treating eczema with just plain Vaseline? People with eczema already know it can be expensive to deal with. The average out-of-pocket costs can be $274 a month, which is more than a third of a typical family’s disposable income. In contrast, you can rub a kid from head to toe with petroleum jelly for about four cents, whereas coconut oil or some of the fancier over-the-counter moisturizers can be many times more expensive, though not as bad as some prescription moisturizers that can cost more than a hundred dollars per tube and work no better than the over-the-counter stuff, as you can see at 5:50 in my video. There is simply no evidence “prescription device moisturizers” are superior to the traditional, petroleum jelly-based over-the-counter products that can be 65 times cheaper.

Doesn’t virgin coconut oil have active ingredients, though, whereas petroleum jelly is just inert? Vaseline has been around since 1872, but it took the scientific community 144 years to put it to the test. We now know it isn’t inert at all, significantly upregulating genes that fight infection, inducing the expression of genes that help with barrier function, increasing the thickness of the protective outer layer of skin, and actively reducing inflammation. Yes, but is it safe? Not… if you inject it into your penis. (What is it with men injecting stuff into their penis?!) “In the less severe cases, the problem [this self-injection creates] could be solved by basic surgery. Otherwise, it may require major reconstruction. Evidently, “Vaseline self-injection of the penis” is done a lot by prisoners, giving a whole new meaning to the term “Jailhouse Rock.” An unbelievable one in six inmates at the largest prison in Hungary admitted to “Vaseline self-injection.” Or how about actual rocks, the surgical implantation of stones in the penis, which has also been reported? What about injecting industrial silicone? (I will never look at silicone caulk the same way ever again.) When men were asked why they were injecting cod liver oil, a fishy substance, into their penises, most explained it was because they felt underendowed, as you can see at 7:40 in my video, but one guy said he “just want[ed] to try.” Um…okay. Why inject cod liver oil into your penis, though, when you can just inject the mercury directly and cut out the middlefish?

Back to eczema! Based on 77 studies of moisturizers for eczema, researchers “did not find reliable evidence that one moisturizer is better than another,” though a consensus of experts concluded that petroleum jelly may be best for skin barrier function protection.

What about eating coconut oil? See Coconut Oil and the Boost in HDL “Good” Cholesterol and What About Coconuts, Coconut Milk, and Coconut Oil MCTs?.

What about the swallowing oil supplements? That was the topic of my video, Eczema Treatment with Evening Primrose Oil vs. Borage Oil vs. Hempseed Oil.

I have more on eczema coming up, so make sure you’re subscribed so you don’t miss anything.

In health, 

Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live presentations: