Effects of intense interval training

NY Times:

A few years ago, researchers at the National Institute of Health and Nutrition in Japan put rats through a series of swim tests with surprising results. They had one group of rodents paddle in a small pool for six hours, this long workout broken into two sessions of three hours each. A second group of rats were made to stroke furiously through short, intense bouts of swimming, while carrying ballast to increase their workload. After 20 seconds, the weighted rats were scooped out of the water and allowed to rest for 10 seconds, before being placed back in the pool for another 20 seconds of exertion. The scientists had the rats repeat these brief, strenuous swims 14 times, for a total of about four-and-a-half minutes of swimming. Afterward, the researchers tested each rat’s muscle fibers and found that, as expected, the rats that had gone for the six-hour swim showed preliminary molecular changes that would increase endurance. But the second rodent group, which exercised for less than five minutes also showed the same molecular changes.

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Iodine in the traditional Japanese diet

In an effort to reap the perceived benefits of the traditional Japanese diet, some alternative medicine practitioners advocate high-dose iodine supplements. Alan Gaby reviews the evidence for this kind of treatment in the Townsend Letter:

While iodine therapy shows promise, I am concerned that two concepts being put forth could lead to overzealous prescribing of this potentially toxic mineral. First is the notion that the optimal dietary iodine intake for humans is around 13.8 mg per day, which is about 90 times the RDA and more than 13 times the "safe upper limit" of 1 mg per day established by the World Health Organization. Second is the claim that a newly developed iodine-load test can be used as a reliable tool to identify iodine deficiency.
Is the optimal human requirement 13.8 mg per day?
The argument, developed by one investigator, (5) that the optimal human iodine intake is around 90 times the RDA is based mainly on two points. The first point is that the average iodine intake of adults living in Japan is 13.8 mg per day, and the Japanese are among the healthiest people in the world, with low rates of cancer. The second point is in regard to the amount of oral iodine that it takes to saturate the thyroid tissues.
The idea that Japanese people consume 13.8 mg of iodine per day appears to have arisen from a misinterpretation of a 1967 paper. (6) In that paper, the average intake of seaweed in Japan was listed as 4.6 g (4,600 mg) per day, and seaweed was said to contain 0.3% iodine. The figure of 13.8 mg comes from multiplying 4,600 mg by 0.003. However, the 4.6 g of seaweed consumed per day was expressed as wet weight, whereas the 0.3%-iodine figure was based on dry weight. Since many vegetables contain at least 90% water, 13.8 mg per day is a significant overestimate of iodine intake. In studies that have specifically looked at iodine intake among Japanese people, the mean dietary intake (estimated from urinary iodine excretion) was in the range of 330 to 500 mcg per day, (7,8) which is at least 25-fold lower than 13.8 mg per day

Gaby has debunked a pervasive myth. Concerning the second point, Gaby examines the rationale for an innovative new testing procedure for iodine deficiency ('iodine loading") and finds it wanting.

Gaby concludes:

The possibility that high-dose iodine/iodide can relieve certain common conditions is intriguing. Considering the positive anecdotal reports, an empirical trial of iodine/iodide therapy, based on the clinical picture, seems reasonable. The case has not been made, however, that the average person should markedly increase his or her iodine intake in an attempt to saturate the tissues with iodine. Nor has the case been made that the iodine-load test can provide reliable guidance regarding the need for iodine therapy. Thyroid function should be monitored in patients receiving more than 1 mg of iodine per day

Reasonable suggestions, I think, based on the evidence.

The original article by Gaby sparked a debate (which I have yet to read). Make of it what you will, here are those posts:

• A Rebuttal of Dr. Gaby's Editorial on Iodine by Guy E. Abraham, MD and David Brownstein, MD
  
• Alan R. Gaby, MD's Response to: A Rebuttal of Dr. Gaby's Editorial on Iodine
  
• Iodine Debate Continues by Guy E. Abraham, MD and David Brownstein, MD
  
• Gaby Responds to Rebuttal #2 by Alan R. Gaby, MD

Update:
Here is a comprehensive study of idodine toxicity.

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How safe are kelp supplements?

Recently, I have noticed that kelp supplements are available just about everywhere. But how safe are they?

An article in the Journal of Dermatology related this horror story:

A 54-year-old woman was referred to the University of California, Davis, Occupational Medicine Clinic with a 2-year history of worsening alopecia and memory loss. She also reported having a rash, increasing fatigue, nausea, and vomiting, disabling her to the point where she could no longer work full-time. A thorough exposure history revealed that she took daily kelp supplements. A urine sample showed an arsenic level of 83.6 microg/g creatinine.

So the researchers conducted a study:

To evaluate the extent of arsenic contamination in commercially available kelp, we analyzed nine samples randomly obtained from local health food stores. Eight of the nine samples showed detectable levels of arsenic higher than the Food and Drug Administration tolerance level of 0.5 to 2 ppm for certain food products. None of the supplements contained information regarding the possibility of contamination with arsenic or other heavy metals.

The researchers warn that under-regulation of supplements may be putting the public in danger:

The 1994 Dietary Supplement Health and Education Act (DSHEA) has changed the way dietary herbal therapies are marketed and regulated in the United States. Less regulation of dietary herbal therapies will make inadvertent toxicities a more frequent occurrence.

My own reaction: it depends how you define "regulation." Contaminated products and products sourced from contaminated environments should be banned entirely. As for uncontaminated products, it's far preferable that the government mandate warning labels than ban products entirely. Why? First, people will turn to unsafe sources if they think the product is helpful -- as happens with street drugs, defeating the purpose of a ban. Second, it's not the role of governments to make choices for people. Improved testing and labeling offers an important and in many respects, urgently required advance on current practice.

The authors further advise:

Clinicians should be aware of the potential for heavy metal toxicity due to chronic use of dietary herbal supplements. Inquiring about use of dietary supplements is an important element of the medical history.

And patients should make themselves familiar with the up-to-date scientific literature on any drug or supplement they consume. This has never been so easy to do.

If you are not familiar with the science, what would be the point of taking any supplement? You could just as easily be putting yourself at further risk!

Finally, I can see two other potential problem with kelp. First, concerns the extremely high iodine content of some species. This may put some people at risk of toxicity. Second, some places where seaweed is gathered may be contaminated by industrial waste or pollutants. And some seaweeds may contain toxic heavy metals such as iron or aluminum. I have read that lead contamination is an issue with various kinds of supplements sourced from China.

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Melissa Etheridge's medical marijuana story

Melissa Etheridge recently explained to CNN's Anderson Cooper that it was only through medical marijuana that she was able to cope with her chemotherapy for breast cancer.



Could THC, a component of marijuana, also prove an effective treatment for cancer? Let's take a look at some of the evidence.

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THC as a treatment for breast cancer?

UPDATES

It's by now fairly well known that marijuana has been used as an adjunct to chemotherapy. Patients who don't respond well to manufactured pain killers have found marijuana a particularly helpful remedy.

What is less well known is the possibility that a component of marijuana, THC ((delta)-9-Tetrahydrocannabinolmay) be an effective anti-cancer agent in its own right. In other words, some studies have found that THC actually kills tumor cells.

What is shocking to me are two facts. First, those rat studies that have been done on THC, mainly in Spain, are promising. Second, just how little research has been carried out on THC. I mean we are talking about a substance that's abundant, easy to produce, and shows some promise in the fight against cancer. Most of the serious research on THC and breast cancer is very recent.

Wast there a cover-up?
http://www.alternet.org/story/9257/

Note date of publication!
http://www.jci.org/articles/view/37948

Also very recent:
http://www.ncbi.nlm.nih.gov/pubmed/19428940?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

http://www.ncbi.nlm.nih.gov/pubmed/18454173?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

A study on human patients:
http://www.asco.org/ASCOv2/Meetings/Abstracts?&vmview=abst_detail_view&confID=47&abstractID=33960

Now, there has been some speculation in medical literature that marijuana could cause cancer.

However, having done some a quick survey, I can't find any studies that amount to anything more than speculation. Most of these discussions seem to relate to the notion that inhaling marijuana smoke might have negative effects on lung cells. We're not talking about actual studies, just theoretical speculation with regard to lung cancer. For example, Tashkin (2005):

The THC in marijuana could contribute to some of these injurious changes through its ability to augment oxidative stress, cause mitochondrial dysfunction, and inhibit apoptosis. On the other hand, physiologic, clinical or epidemiologic evidence that marijuana smoking may lead to chronic obstructive pulmonary disease or respiratory cancer is limited and inconsistent.

The main concern I have with THC is the appalling lack of research, but the good thing is that it has a long history of use -- something that can be said for few modern drugs. Relative to many pharmaceutical substances, the components of marijuana don't appear to pose especially high risk. Although a study done a couple of years ago seemed to link marijuana to schizophrenia in susceptible young people, the finding does not appear to hold up to scrutiny.

If you want to know how to make your own THC oil, some Canadians have produced a how-to guide:

http://www.phoenixtears.ca/diy.html

Update
I came across a US study of mice that appears to indicate that THC contributes to cancer growth in the breast under certain conditions. The authors try to explain the paradox, because it seems to contradict other research.

. . . findings suggest that marijuana exposure either recreationally or medicinally may increase the susceptibility to and/or incidence of breast cancer as well as other cancers that do not express cannabinoid receptors and are resistant to (delta)-⁹-THC-induced apoptosis. . . . .

Although direct epidemiological data linking marijuana exposure to increased incidence of breast cancers is not currently available, it is intriguing to speculate that immunocompromised individuals may become increasingly susceptible to MMTV-like infection and to the subsequent development of breast cancers. Therefore, the possibility exists that exposure to marijuana, either through recreational or medicinal use, may lead to increased incidence of immunogenic tumors.

http://www.jimmunol.org/cgi/content/full/174/6/3281

Update 2
I came across another article , that reviews the findings of the previously cited contradictory study (update 1) and other research on the topic. The athors conclude:

Cannabinoids are proving to be unique based on their targeted action on cancer cells and their ability to spare normal cells. Variation in the effects of cannabinoids in different cell lines and tumor model could be due to the differential expression of CB₁ and CB₂ receptors. Thus, overexpression of cannabinoid receptors may be effective in killing tumors, whereas low or no expression of these receptors could lead to cell proliferation and metastasis because of the suppression of the antitumor immune response. It is also reported that low doses of cannabinoid administration accelerate proliferation of cancer cells instead of inducing apoptosis and, thereby, contribute to cancer progression. Till date, very little is known about the mechanism of action of cannabinoids. There is need for further in-depth studies to elucidate the precise mechanism of cannabinoid action in cancer cells. Safety of (9)-tetrahydrocannabinol administration has been determined, and a dose escalation regimen showed that cannabinoid delivery was safe and could be achieved without overt psychoactive effects. In view of the fair safety profile of most cannabinoids together with their antiproliferative action on tumor cells, clinical trials are required to determine whether cannabinoids could be used for the inhibition of tumor growth in a clinical setting.

http://cancerres.aacrjournals.org/cgi/content/full/68/2/339

So what are they waiting for? Get those clinical trials underway!

Update 3
Here are some webpages linking to various studies about the potential of marijuana/thc in the treatment of various diseases listed here and more here.

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Hazards of core training exposed

NY Times quotes Stuart McGill, a highly regarded professor of spine biomechanics at the University of Waterloo in Canada (McGill’s website is backfitpro.com.):

. . . .a core exercise program should emphasize all of the major muscles that girdle the spine, including but not concentrating on the abs. Side plank (lie on your side and raise your upper body) and the “bird dog” (in which, from all fours, you raise an alternate arm and leg) exercise the important muscles embedded along the back and sides of the core. As for the abdominals, no sit-ups, McGill said; they place devastating loads on the disks. An approved crunch begins with you lying down, one knee bent, and hands positioned beneath your lower back for support. “Do not hollow your stomach or press your back against the floor,” McGill says. Gently lift your head and shoulders, hold briefly and relax back down. These three exercises, done regularly, McGill said, can provide well-rounded, thorough core stability. And they avoid the pitfalls of the all-abs core routine. “I see too many people,” McGill told me with a sigh, “who have six-pack abs and a ruined back.”

You have to approach any exercise advice cautiously, and be prepared to abandon any routine if something starts "not to feel right."

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Indoor air pollution and the rubber duck

CBC:

. . . our indoor sanctuaries aren't as safe as we'd like to think ... not only is the air not clean, but our homes are full of everyday household products that carry harmful toxic pollutants.

Rick Smith is the Executive Director of Environmental Defence. And Bruce Lourie is the President of the Ivey Foundation, an environmental consulting firm. And to prove their point, they turned themselves into human guinea pigs for 48 hours to see what would seep into their systems - from the stuff all around them. They've documented the results in a new book. It's called Slow Death by Rubber Duck: How the Toxic Chemistry of Everyday Life Affects our Health

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