This is Part 6 of a series of six articles discussing various medical uses for cannabis or marijuana. In this part, I summarize all of the five previous articles into some bullet points so that you have quick and fast access to some scientific information about medical uses for cannabis or marijuana.
In case you missed them, here are the first five articles in this series:
Maybe you don’t agree with the science about marijuana’s role in medicine. But that’s not how science works. The evidence should lead you to a conclusion (actually, the acceptance or rejection of a hypothesis). One shouldn’t form an a prior conclusion, then go hunt for data. That’s not how it works.
As new systematic or meta reviews bring more clinical evidence of the benefits of the medical uses for cannabis – this takes time – maybe evidence based medicine can incorporate marijuana into the armamentarium of medical practice. But only real clinical evidence matters.
It’s clear that rational people still want regulations for marijuana, including prohibitions against public smoking (I don’t want second hand cannabis smoke wafting over me or my children, as much as I don’t want to inhale other people’s tobacco smoke). And a safe society would have strict regulations that would forbid marijuana smoking by individuals who have roles in public health and safety like physicians, pilots, mass transit drivers, and others.
But I think those would be reasonable boundaries for legalization of cannabis that would be reasonable to most people. But this is not the point of this article.
As the push to legalize marijuana for personal or medical use gains traction in the USA, there has developed a strong belief, unsupported by evidence, of the value of the medical uses of cannabis. What is troublesome is that the pro-marijuana side seems to make claims about the medical uses of cannabis that appear to be only tenuously supported by real scientific evidence.
In fact, some of the claims are downright dangerous. The reasons for pushing this is probably, though I can only speculate, to make it appear that marijuana is some miracle product, so let’s speed up the legalization of it. It’s like the Food Babe telling us that kale is the miracle food, except that kale isn’t illegal. It does taste awful (but again, not the point).
Because of the amount of scientific information, this article is part 1 of a 5-part series about marijuana and medicine – assessing the science. For detailed analysis of various aspects of the science of marijuana and medicine, check out each of the subtopics:
This is Part 2 of a series of six articles discussing marijuana’s use in medicine and health care. In this part, we discuss marijuana and cancer – probably one of the most passionate and controversial “debates” associated with the use of cannabis.
It’s clear that there are numerous claims about the value of marijuana in preventing or treating various cancers. But what are facts? And what is smoke?
In this article, I’ll look at some of the more prominent claims, along with a skeptical analysis of those claims.
This is Part 3 of a series of six articles discussing marijuana’s use in medicine and health care. In this part, we discuss marijuana and neurological disorders – probably the only field of study regarding medical uses of cannabis that has a robust area of clinical research.
Although research into the use of marijuana and cancer takes all the news these days, there is probably just as vigorous research into neurological disorders. If you read the story regarding CNN’s chief medical correspondent, Dr. Sanjay Gupta, who claimed he changed his mind about marijuana, you’d know he was also convinced that marijuana had some great potential in mental health. But is there really any high quality evidence?
This is Part 4 of a series of six articles discussing marijuana’s use in medicine and health care. In this part, we discuss marijuana and health risks – even if there is evidence that marijuana had medical benefits, there must be a review of the risks of using it.
Only in junk medicine (see homeopathy or chiropractic, for example) is there a promise of great results with no risks. In real medicine, all benefits are balanced against the real risks of any medication or procedure.
The whole foundation of evidence (or science) based medicine is science – “it is the only set of methods for investigating and understanding the natural world.” Thus, the best factual evidence includes clinical research that describes not only the effectiveness, but also the risks, of a particular medical procedure.
This article has been substantially updated, and can be read here. Please read and comment at the newer article.
One of the most tiresome discussions that a scientific skeptic has when debunking and refuting pseudoscience or junk science (slightly different variations of the same theme) is what constitutes real evidence. You’d think that would be easy, “scientific evidence” should be the gold standard, but really, there is a range of evidence from garbage to convincing.
So this is my guide to amateur (and if I do a good job, professional) method to evaluating scientific research quality across the internet. This is a major update of my original article on this topic, with less emphasis on Wikipedia, and more detail about scientific authority and hierarchy of evidence.
In today’s world of instant news, with memes and 140 character analyses flying across social media pretending to present knowledge in a manner that makes it appear authoritative. Even detailed, 2000 word articles that I write are often considered to be too long, and people only read the title or the concluding paragraph. This happens all the time in the amateur science circles specifically. For example, many people only read the abstract and, even there, only the conclusion of the abstract for scientific articles.
As the push to legalize marijuana for personal or medical use gains traction in the USA, the “pro-pot” arguments become more enthusiastic and more off the beaten track of real science. I suspect, like legal same sex marriage, social norms have changed, and legal marijuana is something that will become commonplace across the country, except in some deeply conservative areas. The Federal Government has shown little enthusiasm in enforcing Federal law, which retains the highest authority in regulating certain drugs, in states that allow legal marijuana.
I personally have no issue with smoking marijuana, since other “drugs”, like alcohol, are completely legal and socially acceptable. I think that legalizing marijuana will reduce much of drug trafficking, reduce the burden of law enforcement and penal system costs, and have other beneficial effects to society.
I still want regulations such as control over public smoking (I don’t want second hand cannabis smoke wafting over me or my children, as much as I don’t want to inhale other people’s tobacco smoke), there needs to be regulations about when it might be illegal to be high (I don’t want my Delta Airlines pilot to be smoking weed before flying my jet, and I don’t want automobile drivers to be under the influence), and I want age regulations no different than there is for alcohol and cigarettes (despite . But I think those are reasonable boundaries for legalization of cannabis that would be reasonable to most people. But this isn’t the point of this article.
What troubles me about the “debate” about legalization of cannabis is that the pro-pot side seems to make claims about various medical benefits that appear to be only tenuously supported by real scientific evidence–in fact, some of the claims are downright dangerous. The reasons for doing this is probably, though I can only speculate, to make it appear that marijuana is some miracle product, so let’s speed up the legalization of it. It’s like the Food Babe telling us that kale is the miracle food, except that kale isn’t illegal. It does taste awful (but not the point). Continue reading “Medical uses of marijuana–hitting the bong of science (updated again)”
Let’s start right from the beginning–there is no evidence that acupuncture has any significant clinical benefit for any condition. And because there is a small, but significant, risk associated with the acupuncture, the risk to benefit ratio is huge (if not infinity, since there is no benefit). There is simply no reason to accept, even a small risk, if there is no benefit to a procedure.
Clinical research can never prove that an intervention has an effect size of zero. Rather, clinical research assumes the null hypothesis, that the treatment does not work, and the burden of proof lies with demonstrating adequate evidence to reject the null hypothesis. So, when being technical, researchers will conclude that a negative study “fails to reject the null hypothesis.”
Further, negative studies do not demonstrate an effect size of zero, but rather that any possible effect is likely to be smaller than the power of existing research to detect. The greater the number and power of such studies, however, the closer this remaining possible effect size gets to zero. At some point the remaining possible effect becomes clinically insignificant.
In a previous article, from our vaccine legal expert, Dorit Reiss, we learned that there’s a whistleblower lawsuit against Merck regarding the possibility that the company may have engaged in some inappropriate actions in determining the effectiveness of the MMR vaccine (for mumps, measles and rubella), specifically the mumps component of the vaccine. As Reiss stated, despite the suit (and recent ruling which just whether the case could go forward) being a boon to the antivaccination crowd, so far no facts have actually been presented.
In essence, the whistleblowers claim that Merck, the manufacturer of the MMR vaccine, through either direct falsification or poor study design, may have overstated the effectiveness of the mumps component of the vaccine. Merck had been claiming that the vaccine was approximately 95% effective (meaning at least 95% of children given the vaccine were protected against the disease).
So let’s be clear about this so-called whistleblower lawsuit–no evidence has been presented, and that evidence hasn’t been cross-examined. And one more thing–courts do not decide science, it’s not their role. Science is not a debate, it is a cold evaluation of evidence. And in science, the weight of the evidence is both in quality and quantity. Unless you’re a complete anti-science cult member, whatever this court decides, whatever malfeasance was practiced by Merck, whatever the whistleblowers have to say, the scientific evidence tells us that the mumps vaccine component is highly effective and extremely safe. Continue reading “Mumps vaccine effectiveness and waning immunity”
Lots of people take vitamin D supplements to keep their bones strong as they age, advice that is pushed by legitimate organizations, like the National Osteoporosis Foundation. But does vitamin D actually do anything, or are their effects some kind of myth?
The researchers determined that vitamin D supplements did not usually increase bone density for people who already had normal levels of vitamin D. Although bone density did improve in the femur, the longest and heaviest bone in the human skeleton, all other bones did not exhibit a higher density after vitamin D.
The systematic review included 23 previously published studies (comprising a total of 4082 participants, 92% women, average age 59 years) who received vitamin D supplementation over an average of 23.5 months. Bone mineral density was measured at one to five sites (lumbar vertebrae, femoral neck, total hip, trochanter, total body, or forearm) in each study.
The studies included in the review had differing vitamin D supplementation regimens. The vitamin D dosages, as well as the length of the treatment, varied across. On average, 500 IU (international unit, with each unit being the biological equivalent of 0.025 μg cholecalciferol/ergocalciferol) was the daily dose in six of the studies, 500-799 IU was used in four studies, and 800 IU or more was used in 13 studies.
Across all of the studies, 70 tests of statistical significance were performed. Of the 70, six had findings of significant benefit of vitamin D supplementation, two showed significant detriment, and the rest, 62, show no significant benefit or detriment. Of all the studies, only one showed a benefit at more than one bone site. And more supplementation did not show any benefit, so there was not a dose-reponse effect.
Most importantly, of the studies that did report improvement in bone density, the finding was not significant enough to prevent a bone from fracturing after a fall. Surprisingly, the researchers also discovered that doses of less than 800 IU per day were more effective for improving bone density in the spine.
The researchers concluded that “continuing widespread use of vitamin D for osteoporosis prevention in community-dwelling adults without specific risk factors for vitamin D deficiency seems to be inappropriate.” In other words, the evidence does not support the hypothesis taking vitamin D provided a benefit of increased bone density in individuals who already had healthy levels of vitamin D–supplementing with vitamin D was not necessary for most adults over the age of 55. Moreover, the researchers recommended that healthcare providers should target individuals who may not be getting sufficient vitamin D naturally, such as through exposure to sunlight, with either vitamin D supplementation or sunlight therapy.
To answer the original question? Yes, vitamin D supplementation is a waste of money, unless there specific issues that would indicate that it would be useful, such as in individuals who do not make sufficient vitamin D naturally. And no, more vitamin D does not help.