Bringing Home the Bacon – I’m a Cancer Survivor with Meat on the Menu.

baconThis week, the World Health Organisation (WHO) classified processed meat as being carcinogenic to humans and red meat as a probable carcinogen. Bacon has become the darling of the foodie world over the past couple of years, with bacon-flavoured popcornmilkshakes and lollipops on the market, so does this new labelling mean that a package of bacon will be slapped with a warning sticker, and every hotdog will come with a side of medical advice?

Although the overall risk of developing colorectal cancer is small, headlines citing an 18% increase in colorectal cancer risk from consuming one 50 g serving of processed meat per day (approximately one hotdog) have led to consumer concern – including the (incorrect) assumption that eating 5 portions of processed meat would therefore lead to a 90% certainty of developing colorectal cancer.

Let’s examine the real risk.  The average person’s risk of developing colorectal cancer is approximately 5%. If the WHO data suggesting an 18% increase in risk is correct, a daily 50 g serving of processed meat increases that risk to 5.9 % (an increase slightly less than 1 people per 100), of which between 0.65 – 5.4 people will survive for 5 years or more (depending on cancer stage at diagnosis). Despite the increase in meat consumption over the past century (and therefore assumed increase in processed meat consumption due to changes in dining habits and food availability), the death rate from colorectal cancer has dropped over the past 20 years. Moreover, in media articles discussing the WHO announcement, there is no mention of mitigating factors such as fruit and vegetable consumption. What happens if I eat 50 g of bacon within a huge salad with a side of oat bread, a meal high in dietary fibre, which is cited as having a protective effect against colorectal cancer? Or if I eat bacon after running five miles, given the role of exercise in preventing cancer? As with so many other health risks, it’s almost impossible to assess the impact of meat consumption in isolation.

Both alcohol and cigarettes are already listed as carcinogens by the WHO, yet how many people have actually forgone a glass of wine or pint of beer based upon the fear of cancer? By contrast, how many have cheerfully raised a glass to headlines stating that red wine may have beneficial health effects? Rather than health benefits, this announcement may reduce meat consumption by people who are most vulnerable to health complications from nutrient deficiencies (e.g. growing children, pregnant women and elderly people); not to mention the undoubted glee of anti-animal agriculture groups who will welcome the gift of further ammunition against meat consumption.

As a cancer survivor, I am the last person to downplay the importance of minimising cancer risk. However, ultimately we will all die and almost everything we do, from driving a car to choosing salad ingredients, carries some risk to health. Rather than the continuing mass of conflicting evidence, where every week a new article warns us about the latest cancer-causing drug/chemical/food; we need a balanced assessment of all cancer risks in order to make the best choices. I don’t smoke and I have had less than 10 alcoholic drinks in the past 2.5 years, but bacon remains on my dinner menu tonight.

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Got Ebola? Just Take Some Vitamin C.

Ebola

It appears that the lunatics are taking over the asylum. This is another post about “things that irritate me” – just a short rant this time about bad science and fear-mongering. The current irritant is the Alliance for Natural Health (ANH; as publicized by the Organic Consumers Association), which claims that Ebola can be prevented and treated naturally, but that these remedies are being (gasp!) “ignored by doctors and the government”.

If you’re really concerned that you may catch Ebola, the easiest way to avoid it is not to have intimate contact with an infected person’s bodily fluids; but never fear, if you do, the ANH have a list of “proven” natural remedies that will stop Ebola dead in its tracks. For example, Ebola is selenium-dependant, making people who’re already selenium-deficient more vulnerable to the disease, so if you just load up with mega-doses of selenium, you’ll be fine. Equally, both silver and vitamin C are antiviral, so add these to your selenium cocktail and you won’t just be fine, you’ll be invincible!

There’s just one problem – none of these miracle remedies have actually been tested against Ebola, which ANH claim is because of government/big drug conspiracies. It’s true that increasing your intake of selenium and vitamins C, D and E should boost your immune system to a degree, but you can’t then have a long smooch with somebody who’s infected with Ebola and expect to be immune. More importantly, given the ANH’s claims of natural “treatment”, there is zero evidence that any of these purported remedies provide a cure.

Most worrying of all is the final tagline: “Alert! Write to both FDA and Congress. Ask them to review natural treatments for Ebola without the lengthy drug approval process“. This lengthy drug approval process exists to ensure that drugs are safe, efficacious and do not cause unexpected or severe side-effects. It costs drug companies millions of dollars to get a single drug to market through this process, which is required for every new drug in order to protect our health. Furthermore, “natural” chemicals are not safe or effective simply because they exist in nature. Arsenic, cyanide and mercury are all inherently natural, as are deadly nightshade and death cap mushrooms. The “action alert” above is an example of bad science and fear-mongering at its worst – a dangerous remedy that will do nothing to halt the spread of the disease – and will probably hasten the patient’s death in the process.

One In Five Children Who Contract Diphtheria Die – Are Anti-Vaccination Activists Dangerous, Or Simply Misinformed?

vaccine1I had the pleasure of speaking in the plenary session at the 2014 AAVLD/USAHA Annual Meeting this week, where, among other topics, we discussed risk. One of the other panelists made the best point that I’ve heard in a long time – activists hate denominators.

Think about the last few scare stories you’ve seen – there’s no doubt that it is frightening to read that 3,000 people die from food poisoning each year, or that, to date, 4,546 people have died from Ebola (one in the USA). Yet if we put this into context, one person out of 315 million in the USA dying from Ebola is a tiny tiny fraction, and a correspondingly tiny risk.

Activists hate denominators because they provide us with context, a way to assess whether we’re really in danger. Statistically speaking, you’re  more likely to die from a traffic accident (one in 71 deaths), flu (one in 1,642 deaths), or syphilis (one in 55,866 deaths) than Ebola (one in 2,515,458 deaths). Which brings me to my current favorite activist, anti-vaccine zealot and proponent of “well-researched” bad science, Modern Alternative Mama (MAM). Thus week, she’s been promoting what she optimistically calls a “risk:benefit analysis” of the DTaP (diphtheria, tetanus and pertussis) vaccine.

Interestingly, she appears to consider all vaccine risks equal: death is no more of a minor inconvenience than redness at an injection site, and she earnestly notes that there is “no known benefit to getting diphtheria“. That sentence alone causes the mind to boggle. On a positive note, she does use valid CDC data, reporting that there were 3,169 adverse effects attributed to DTaP in 2011, which she claims is an underestimate of up to 9-fold.

So let’s run the numbers. Each year, approximately 3.95 million babies are born, of which 82.5% are given the DTaP vaccine. Between birth and 6 years of age, 5 doses of DTaP are recommended, so each year, 5 x 3.95 million x 82.5% = 16,293,750 doses are given (note that babies will have three each in that year, but older children (18 months and 4-6 years) will also receive a dose). Let’s give MAM the benefit of the doubt and assume adverse vaccine events are actually 5x the cited CDC number, at 15,845 events. The CDC classifies 10% of these events as “serious”, which equals 1,585 serious events per year.

So what is your child’s chance of having a serious reaction to the DTaP vaccine? 1,585/16,293,750 = 0.0000973, or one in 10,277 children will have a serious reaction to DTaP.

By contrast, we could take our chances in not vaccinating and hope that our child doesn’t contract diphtheria, which carries a risk of death of up to 20% in children under five years old. That means one in five children who contract diphtheria will die.

Given MAM’s antagonism towards vaccines, it’s not altogether surprising that she concludes “Although diphtheria is serious, it appears that the risk from the vaccine is much greater.” Yet let’s be realistic about this. One in 10,277 children will have a serious reaction to DTaP (serious reactions does not mean death, although that is one possible outcome) versus one in five children who will die after contracting diphtheria.

Admittedly that’s assuming that all unvaccinated children will get diphtheria. They won’t, but even if only 5% do, the risk is still overwhelmingly lower in the vaccine category (one in 10,277 suffering a serious reaction to the vaccine vs. one in 100 dying from diphtheria).

The site carries a disclaimer that writers are neither education professionals nor providing medical advice, yet the suggestion (by the author herself) that this is a well-researched, scientific post will no doubt cause some parents to congratulate themselves on their choice to not vaccinate.

This pseudoscientific scaremongering is dangerous, potentially lethal. All parents are concerned for their children’s health and welfare, but propounding nonsensical “risk:benefit analyses” that do not consider the denominator but simply the total adverse effects does not allow any parent to make a rational and well-considered decision. If my child is the one in 10,277 who suffers a serious DTaP vaccine reaction, I’m unlikely to care whether she is one of few or many, but at least I can make the decision whether or not to vaccinate (my answer is an overwhelming “yes”) based on risk. We all want our babies to grow up healthy and happy – in this case, it’s time to be a mainstream vaccinating Mama, rather than a “modern alternative” one.