Eating meat causes cancer – let’s get this right

eating meat causes cancer

Oh here we go again. Everything causes cancer. Time to move into a a giant bubble and eat nothing but GMO, 100% gluten wheat bread. Now, eating meat causes cancer.

Unless you don’t have a Facebook and Twitter account (and who doesn’t these days), your timelines were flooded, literally, with memes, articles, and uptight vegans laughing at everyone because the World Health Organization stated that eating meat causes cancer – that’s either processed meat, like a good French sausage, or unprocessed red meat.

Back to my giant bubble.

For all of you with good scientifically skeptical minds, this story has already been parsed and dissected, and you’ve moved on. That’s what I did, as I sliced some excellent French sausage and ate it with my GMO crackers.

But then I thought, well if this is a thing, should I be worried? Should my non-vegan carnivore readers be worried?

Let’s look at this every way I can. Maybe there’s enough evidence to convince some or all of us to modify our behavior. Or not.

I’m charging ahead, brave readers – read on. Continue reading “Eating meat causes cancer – let’s get this right”

Electronic cigarette dangers – new research

electronic cigarette dangers

Note – this article has been updated with new research and information about electronic cigarette dangers. Please comment there, as the comment section for this article is closed.

Over the past few years, electronic cigarettes (often called a personal vaporizer, e-cigarette, or many other trendy descriptions–I’ll abbreviate them as EC, just to save space) have become a popular alternative to tobacco cigarettes. They originally were developed as a tool to quit cigarette smoking, which is factually linked to lung cancer and other respiratory diseases.

However, ECs have become much more than a tool to end smoking, but they have evolved into popular subculture phenomenon known as the “vaping community” that, in many respects, seem to mimic the marijuana advocates. The vaping community continues to push a belief that ECs are safer than traditional cigarettes, have little health risk to the vaper (electronic cigarette smoker), and is much more socially acceptable than smoking cigarettes or cigars.

Continue reading “Electronic cigarette dangers – new research”

Breast cancer risk – lifestyle choices

breast cancer risk

The myths about cancer risk are both sad and dangerous. Too many times, I read about supplements or diets that stop “cancer” as if it’s one disease (it is not) that a handful of blueberries will destroy. Like almost every cancer, reducing breast cancer risk really boils down to a handful of lifestyle choices.

In 2015, there will be 232,000 new breast cancer cases in the USA (pdf). Worldwide in 2012, it was estimated that there were over 1.7 million new cases of breast cancer. There is evidence that the rate of breast cancer is increasing, but that may be a result of better diagnostic tools that give earlier diagnoses (and this is a discussion left for another day).

Breast cancer has become a part of our culture, partially because the disease moved from a disease that was only mentioned in whispers to one that has some of the highest awareness for cancers.

Using a review article, by Max Dieterich et al.  about breast cancer risk and lifestyle influence as a template, I thought it would be prudent to list out some of the major influencers on breast cancer risk. And no, smoking weed has no known influence on the risk of breast cancer.

Continue reading “Breast cancer risk – lifestyle choices”

Correlation does not imply causation – except when it does.


Editor’s note – this article has been substantially updated, and the new version has been republished here.

One of the central tenets of the pro-vaccine world is that correlation does not imply causation – but it is misused and frequently abused by many writers. We, the pro-science/pro-vaccine world, dismiss correlation, if real correlation can be shown, as robust evidence indicative of any causal relationship.

Conflating causation and correlation is somewhat different than the logical fallacy of post hoc ergo propter hoc, where one thinks one event follows the first event because of the existence of the first event. I’m sure all good luck charms and superstitions, like walking under a ladder, are related to the post hoc ergo propter hoc fallacy. So if I walk under a ladder, then trip on a black cat, then crash into a mirror, I don’t immediately blame the initial act of walking under the ladder. I just assume I’m clumsy.

Correlation and causation are a very critical part of scientific research. Basically, correlation is the statistical relationship between two random sets of data. The closer the relationship, the higher the correlation. However, without further data, correlation may not imply causation, that the one set of data has some influence over the other. Continue reading “Correlation does not imply causation – except when it does.”

Part 4. Marijuana and health risks – assessing the science

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.

In this article, I’ll look at marijuana and health risks – along with a skeptical analysis of those claims. Continue reading “Part 4. Marijuana and health risks – assessing the science”

Smoking cannabis doesn’t cure cancer but it may cause it

Marijuana_Cures_CancerAs I have written before, there is a lot of controversy about medical uses for marijuana, although it appears to be much more of a political debate than a scientific one. There just isn’t much evidence that supports a hypothesis that marijuana has any significant therapeutic effect on diseases like cancer, neurological disorders, or other diseases.

Scientists have long suspected that smoking marijuana could be linked to lung cancer, but there has only been weak evidence supporting a causality.  Recently, a 40 year review of  over 49,000 men strongly suggests that smoking cannabis does indeed increase the risk of lung cancer. The study examined 49,321 men between the ages of 18 and 20 who were being enlisted in the Swedish military between 1969 and 1970, examining their health and lifestyle issues, along with their use of marijuana. The researchers reviewed other potential risk factors such as respiratory disease, other types of smoking, and socioeconomic status. Continue reading “Smoking cannabis doesn’t cure cancer but it may cause it”

Regarding those mistakes made by science…

ddt-is-good-for-meI know I shouldn’t use the conspiracy theory fallacy when talking about the pseudoscience-pushing science deniers, who are the bread and butter of topics for skeptics. But, when I keep observing the same ridiculous and insanely illogical arguments used in the same manner by all of the deniers, I begin to wonder if they don’t get together annually at the International Society of Pseudoscience meeting, usually held in Sedona, Arizona, ground zero of woo. They obviously share their stories, because we hear the same regurgitated stories in different contexts.

The antivaccinationists, creationists, anthropogenic global warming deniers, and whomever else pretends to use science to actually deny science frequently focus on a trope that “science makes mistakes.” And then they produce a list of historical events that “prove” that science is wrong. Of course, this indicates more of a misunderstanding of what is science and the history of science than it is a condemnation of science. But your typical science denier is probably not going to let facts get in the way of maintaining faith in their beliefs. So let’s deconstruct and discredit these “science makes mistakes” tropes.

By the way, in my story, I admit that “science makes mistakes,” so read on. Continue reading “Regarding those mistakes made by science…”

Vitamin D reduces breast cancer risk–is there anything to it?

vitamin-DOne of my favorite topics to debunk is the use of supplements to prevent (or worse yet, cure) cancer. As I have discussed in the past, supplements are, with just a couple of exceptions, worthless in preventing cancer

Potential causes for cancer are numerous. InfectionsRadon gasCigarette smokingSun exposure. Obesity. With over 200 types of cancer, each with a different pathophysiology, there may be an equal (and probably greater) number of causes for “cancer.” Although many causes of cancer can be easily avoided, such as stopping smoking, testing your house for radon, getting an HPV vaccine to prevent human papillomavirus infections, and wearing sunblock to reduce the risk of melanomas, the sheer complexity and number of types of cancer means that there is probably not going to be any simple panacea to preventing (or even curing) cancer. 

But because cancer is so frightening, and treating it is risky, debilitating and, in some cases, fruitless, we look for the easy solution, the easy prevention with a pill. But the evidence science has found indicates that this doesn’t really work. Of course, according to 2012 cancer statistics, 577,000 people died of various cancers in 2012, and about 160,000 died directly as a result of smoking (or second hand smoking). So, you can easily drop your risk dying of cancer by more than 25% just by quitting smoking. Otherwise, it’s just not that simple. Continue reading “Vitamin D reduces breast cancer risk–is there anything to it?”

How pseudoscience makes its case-Part 2. Revised and repost.

Recently, we discussed how science works. It’s not a belief. It’s not a random set of rules. It is a rational and logical process to determine cause and effect in the natural world. Pseudoscience, by its very nature, ignores the scientific process; instead, it claims to come to conclusions through science, usually by using scientific sounding words, but actually avoids the scientific process.  They tend to use logical fallacies to make their case.  Just to be clear, logical fallacy is essentially an error of reasoning. When a pseudoscientist  makes a claim, or attempts to persuade the public of this claim, and it is based on a bad piece of reasoning, they commit a fallacy. Continue reading “How pseudoscience makes its case-Part 2. Revised and repost.”

How pseudoscience makes its case. Part 2.

Recently, I discussed how science works. It’s not a belief. It’s not a random set of rules. It is a rational and logical process to determine cause and effect in the natural world. Pseudoscience, by its very nature, ignores the scientific process; instead, it claims to come to conclusions through science, usually by using scientific sounding words, but actually avoids the scientific process.  They tend to use logical fallacies to make their case.  Just to be clear, logical fallacy is essentially an error of reasoning. When a pseudoscientist  makes a claim, or attempts to persuade the public of this claim, and it is based on a bad piece of reasoning, they commit a fallacy.

There are several types of logical fallacies that they employ.  My favorites are Appeals to Antiquity, or old ideas are somehow better than new ideas; Appeals to Authority, or someone who should know better supports the claim even if everyone else does not; Appeals to Popularity, or everyone does it, so it must be useful; and the Genetic Fallacy, where the source is more matter than the merits of the evidence.  Logical fallacies are so prevalent in skeptical community, there are websites devoted to describing them.

The typical pseudoscientist will use logical fallacies to state very definitively that “it’s proven.” It’s the same whether it’s creationism (the belief that some magical being created the world some small number of years ago), alternative medicine (homeopathy, which is nothing but water, has magical properties to cure everything from cancer to male pattern baldness), or vaccine denialists (I’ve discussed this topic before, no need to belabor).  The worst problem is that in the world of the internet, if you google these beliefs, the number of websites and hits that seem to state that they are THE TRUTH overwhelm those that are more skeptical or critical.

So how can you tell the difference between science and pseudoscience in medicine? In medicine, we gather and analyze evidence in one of two ways.

Almost any medical product, device, drug or procedure must, by law, must studied in a Randomized Controlled Trial, which is sometimes called a clinical trial. Essentially, it is a scientific experiment, designed to test the hypothesis of whether the safety and efficacy of a particular medical product is better than a placebo. That is, does the medical product produce results better than doing nothing at all. This is the “gold standard” of investigation, and if the study does confirm the hypothesis, you can be assured it has a benefit to your life (although the degree may be subject to argument). Alternative medicine just doesn’t do this (most of their reasoning is that their beliefs just doesn’t fit into the clinical trial model), so their is no proof that their products work. A clinical trial usually has thousands of participants, and is done in a manner that the patient and the physician do not know who is and who is not receiving the treatment. The results are analyzed statistically and published in peer-reviewed journals. Furthermore, the results are reviewed and investigated by the FDA (and legal bodies in other countries), before a drug or device can be used by a physician. This is an expensive and time-consuming process, in which alternative medicine hardly ever participates.

Now it’s not ethical to test every medical hypothesis with a clinical trial. For example, we know that smoking is bad for your health. Yet, tobacco manufacturers love to insist that there has never been a clinical trial that makes this conclusion. The reason that is true is that it would be unethical to give one group of adults cigarettes for 20 years and another group nothing to see if one would die at a higher rate. So we use epidemiological studies to determine if we can see in a population whether a cause has an effect. We can review records of thousands of smokers to see what the effect will be. Once again, pushers of alternative medicine therapies have not published a study of all the patients who might have used their therapy and see the result. Epidemiology is a scientific process that is critical to preventative medicine–without it, we cannot know if some behavior or public health issue has a causal effect on health.

Remember, anecdotes (“my mother’s friend’s cousin’s daughter was cured by eating this leaf”) are not reasons to accept alternative medicine. Even anecdotes that try to sound like science (“90 out of 100 people think this leaf does work”) aren’t a reason to “believe” in a pseudoscience.

You might have heard that taking lots of Vitamin C helps prevent colds. It doesn’t. And that conclusions is supported by large clinical trials, so unless you are afflicted by scurvy, there’s no reason to take large doses of the vitamin. And that’s the difference between real science and pseudoscience.