Natural Isn’t Safe

When used to describe food, medicine or other products, natural is often used to imply safety. However this association is demonstrably false. There are a huge number of natural things that are extremely dangerous. There are the obvious, venoms (snakes, spiders, jellyfish, etc), toxins found in mushrooms and poisonous plants and heavy metals (mercury, lead, etc, all of which occur naturally in the environment). Some things that are safe for some people, like peanuts, can be deadly to others. Further many substances are safe in some (or most) conditions, but become dangerous in others. For example ever water can be toxic if one drinks too much too quickly, (see Water Intoxication). Thus the claim that a substance is safe simply because it is natural is clearly false.

The only reliable way to tell if substance is safe, be it natural or not, is to test it. However even substances that are found to be safe via testing, should only be assumed to be safe within the limitations of the tests. There are few substances that people assume to be as safe as pure water. However every few years someone gets sick or dies after purposefully drinking too much water. Simply because normal amounts of water is safe does not mean that large amounts is also safe.

Natural Isn’t Healthy

The other major false association that is that natural is healthy. Most of health problems, world wide, are the result of perfectly natural causes. Disease is probably the biggest health issue and most diseases are caused by bacteria, viruses and other pathogens which are perfectly natural. In the developed world, where better sanitation and access to modern medicine makes these diseases rare, we are faced with issues of excess. Fat, sugar and carbohydrates are all natural ingredients in the food we, and our ancestors, eat. However today the ease of access to food has lead to a different set of diseases, caused by the excessive consumption of these natural ingredients. Thus simply because something is natural does not mean it is healthy.

Corollary: What Unnatural Isn’t

An equally important point, is that unnatural is no more unsafe or unhealthy than natural, which means, the only way to determine if something is safe, natural or otherwise, is through testing.

So what’s the point?

Every so often we discover something new, either natural or not. Instead of blindly accepting something because it is natural or dismissing it because it is not, we need to test it. Only through testing can something be determined to be safe and the limitations of its safe usage.

Hopefully the next time you see an ad for a food, supplement, face cream, drug, etc that says “all natural ingredients” you won’t be fooled into thinking that means much more that if it said “now comes in blue”.

Immunization: The most successful public health measure

In the last century, vaccines have saved more lives than any other health
intervention. The World Health Organization estimates that every year, more
than two million deaths are prevented worldwide due to immunization.

Immunization is an important, cost-effective and successful public health
intervention. It effectively prevents disease, improves the health of
Canadians, and reduces pressures on our health care system.

Diving deeper into these pages we find:

Canadian Immunization Guide Seventh Edition – 2006

Which is a very in depth review of the current immunization recommendations.
There is lots of information here, but for me, the most interesting page is
this:

Comparison of Effects of Diseases and Vaccines

Which directly compares the risk of a disease with the risk of the associated
vaccine. This page provides a really nice summary of the risk verses reward
for the various vaccinations. I won’t get too in depth, this page is pretty
easy reading. However I think it is useful to crunch the numbers for an
example. Lets look at Measles. From the article:

Measles

Disease Description and Risks

Complications such as bronchopneumonia and otitis media occur in about 10%.
Encephalitis occurs in 1/1,000 cases (fatal in 15% and neurologic sequelae in
25%). Subacute sclerosing panencephalitis is a rare but fatal complication.
Case fatality < 0.05%. With 2-dose schedule, indigenous measles has been
eliminated in Canada.

Disease Rates, Pre-vaccination

5-year period: 1950-1954
Avg. annual rate: 369.1/100000
Peak annual no: 61,370 cases

Vaccine Description and Risk

Measles vaccine is given in combination with mumps and rubella (MMR). MMR
vaccine: Malaise and fever, with or without a non-infectious rash in about 5%;
up to 1% of recipients may develop parotitis, about 5% have swollen glands,
stiff neck or joint pains. Transient arthralgias or arthritis may occur and
are more common in postpubertal females.

About 1/30,000 develop transient thrombocytopenia, 1/1 million develop
encephalitis.

Disease Rates, Post-vaccination

5-year period: 2000-2004
Avg. annual rate: 0.2/100000
Peak annual no: 199 cases

Analysis

Risk from Measles

Lets look at the rates of serious complication for measles. Encephalitis in
1/1000, with 15% of those leading to death and another 25% leading to
neurologic sequelae (neurological damage). 15% of 1/1000 is
approximately 1/7000, i.e. measles is fatal in about 1/7000 cases.
Neurological damage occurs for about 1/4000. The average number of cases for the
pre-vaccination years was 369.1 cases per 100000 Canadians. If we estimate
today’s population at 33 million, there would be about 121000 cases this year,
leading to 17 deaths and 30 cases of neurological damage from encephalitis. Of
course, because of vaccination this is not happening. However those numbers
1/4000 and 1/7000 still apply to anyone unlucky enough to catch measles.

Note these risks are for healthy individuals in wealthy countries, the
risks in developing nations with poor nutrition and health care are
significantly higher, with death rates as high as 28%

Risk from Vaccines

The common side effects are mild and temporary, so they are not of significant
concern. Lets focus on the serious risks.

Transient thrombocytopenia (a lack of platelets in the blood): 1/30000
Thrombocytopenia can lead to bleeding and bruising issues. Unfortunately I am
not qualified to make any real statement about the severity of
thrombocytopenia, so I suggest you read the article I linked to. However I can say
that 1/30000 is significantly lower risk that 1/7000, the risk of death from
measles, which is the most unlikely result. To put 1/30000 in context, your
risk of dying in a car accident is about 1/10000, so the
risk of this side effect is 3 times lower than the risk of dying in a car
accident.

Encephalitis:

1/1000000 (1 in a million)

The risk of encephalitis from the vaccine is about 1000 times less likely than
encephalitis from measles. As a comparison, the risk of being murdered in
Canada (in 2006) is about 1.8/100000 , or 18 in
a million, so the risk of being murdered is 18 times higher than the risk of
encephalitis caused by the MMR vaccine.

No one gets measles any more

It is important to note that measles is still endemic in various locations around
the world, meaning that every year cases are imported into Canada by travellers.

http://www.insidetoronto.ca/News/NorthYork/article/48756

Measles is an airborne pathogen, thus it is very contagious, simply being in
the same room (or on the same plane) as sick individual is close enough
contact to become infected:

http://www2.canada.com/calgaryherald/news/story.html?id=80df07ef-3abf-477c-a371-ba6d13370b99&k=80923

Further, travelling to a location (India, Africa) where measles is still
endemic would be very risky.