The Superhero or Pseudo-hero of Veggies?
One of the many blessings I’ve received in my life is amazing mentors who are highly esteemed colleagues and well-known experts in various subjects. Their love of learning and sharing of information to me is something I hold dearly. Recently, I have had the pleasure of conversing with one of the top practitioners in functional medicine. During one of our discussions, the topic of thallium in kale came up.
As the subject was brought to my attention, I did experience a rather blurry and vague recollection of reading about plants accumulating heavy metals in contaminated areas from past articles. However, I wasn’t aware of the latest negative press of this super-power veggie. In fact, kale holds the distinguished privilege of being listed amongst the honorable mentions of the American Institute for Cancer Research. It seems just as people can be acclaimed for their amazing talents one minute then found in tabloids the next, even a vegetable can’t have its own national day of celebration without haters. Kale is currently the robust recipient of negative media attention.
According to Medical Daily:
People are still crazy for kale, but is it as healthy as we think it is? In an article for Craftsmanship magazine, molecular biologist Dr. Ernie Hubbard thinks not. According to him, there may be a link between kale and thallium poisoning, along with other toxic metals, as a result of using coal ash spread for fertilizer.
This isn’t the first controversy kale has been up against. There’s the ever-famous goitrogen controversy, upon which kale and broccoli alarmists have been focusing for a while. However, this is probably not a major issue if you are iodine sufficient, goiter free, and steaming your dark, leafy greens. In fact, regarding this thiocyanate issue, which can be excreted in urine and breath, most experts agree that the benefits of glucosinolates probably outweigh the risks for those who are iodine sufficient.
Back to the Metals
After this subject was brought to my attention by this long document, which I read all the through, I came to the conclusion that it may be a good idea to summarize some facts on thallium so you can understand the concern.
Thallium is a soft and malleable metal with a bluish-white color. It is found ubiquitous in the earth and the main uses are in the electrical and electronic industries and in the production of special glasses, scintigraphy in diagnosis of melanoma, and compounds in biochemistry. It is released into the environment from mineral smelters, coal-burning power-generating plants, brickwork, and cement plants.
It is not currently classified as a human carcinogen, but does have a toxicity that is reported between 20-60 mg/kg body weight, although levels as low as 10-15 mg/kg have been reported as lethal. Its half-life is 10-30 days, with most accumulation in kidneys, but it can find its way into all tissues. Some acute and chronic symptoms of toxicity include: diarrhea, skin changes, hair loss, nervous issues, respiratory failure, and cellular changes which can occur (including mitochondrial dysfunction).
The Kale-Scare Caveats
However, there are some common themes I want to also address in the kale scare:
- Most studies that are discussing thallium-contaminated kale are from plants located (artificially or naturally) around contaminated areas from mineral smelters, coal-burning power-generating plants, brickwork, and cement plants.
- Excess thallium exposure is also suspected in areas of water contamination, high pesticide use, and sewage sludge.
- There’s been other articles that link other contaminants in our water and the environment that could be contributing to a total body burden, rather than just pointing to the issue of thallium. In other words, did the doc’s patient improvement in symptoms in the highlighted article come from removing kale from her diet or from decreasing consumption veggies from contaminated soil?
What Can We Do To Have Our Greens & Eat Them Too?
I admit, heavy metal transporters in plants do bring excess metals from their cytoplasm to vacuoles. But, there are some things we can do to mitigate their detrimental effects on us.
- Consider the fact that essential minerals can help support the body’s ability to detoxify toxic metals and mitigate oxidative stress and cellular damage. For example, there’s evidence of selenium, vitamin C, and vitamin E, to assist with decreasing overall heavy metal body burden. However, you want to use them in balance and with a qualified practitioner.
- There’s some evidence that ion-exchange filters can remove thallium, so rinse your kale in non-contaminated water.
- If you live in an area that has industry from mineral smelters, coal-burning plants, brickwork, or cement plants, it may be best to eat frozen kale from other areas of the world that are less contaminated. (Click here to learn more.)
- Take this quote from World’s Healthiest Foods to heart, “: “we believe that you can still lower your risk of thallium-contaminated vegetables to an acceptable level by purchasing certified organic vegetables or their equivalent. At least in one respect, you are guaranteed to lower your risk since sewage sludge cannot be used in the production of certified organic foods, and this type of fertilizer typically contains unwanted amounts of thallium. In addition, organic certifiers are required to follow the EPA guidelines for water contamination as set forth in the federal Clean Water Act (CWA)…”
- Rotate in different forms of veggies and don’t stick to one source, different plants have different phytonutrients and different capacities to hold and excrete heavy metals. Heck, these plants may even be protecting us from our environment by sequestering the metals, just don’t eat too many of the ones that are holding onto lots of them bathing in coal ash, sewer sludge, and rinsed with water containing high doses of thallium!
Back to School Support with Essential Oils
For a change of pace, I blogged a little bit about essential oils on Saratoga.com this month. This way, my Saratoga readers could learn more about oils for wellness. Click here to read more.
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