I’m on the record as stating that cholesterol is not even close to the most important risk factor for cardiac disease, that the benefits of statins are small for most people, and that there are much more important things than cholesterol to focus on for overall health. This puts me a bit at odds with the “mainstream medical establishment,” and somewhat in league with the contrarians and “cholesterol sceptics.” On the flip side, I’m also on record as stating that this doesn’t mean cholesterol doesn’t matter at all, and that I believe statins do in fact have a role to play for select patients. Which puts me in conflict a bit with the above mentioned cholesterol sceptics. To quote the late, great Gerry Rafferty: “Here I am, stuck in the middle with you.”
With that bit of table setting out of the way, I want to share my thoughts on a critique that I often hear from the cholesterol sceptics, which goes something like this: heart disease was extremely rare before the 20th century. Humans have been eating meat, cheese, butter, and eggs for thousands of years. Hence, cholesterol can’t be the cause of heart disease, since presumably people living in prior periods of history had high cholesterol, yet rarely suffered heart disease.
This is an interesting argument, because I think it in fact has some merits to it, but simultaneously some flaws that are worth unpacking.
The first question that must be answered when evaluating this argument is: is it in fact true that heart disease was rare before the 20th century? If so, this should certainly influence our thinking. However, it is unfortunately impossible to answer the question with precision.
Certainly recorded episodes of heart disease were much rarer in say the 1800s than in the 1900s. However, it is important to remember that doctors of the time understood much less than doctors of today, and also had far fewer diagnostic tools. The EKG, for example – which is one of the cornerstone tests for diagnosing heart attacks – was not even invented until the early 1900s. We do know that scientific examinations of mummies from Egypt and of pre-historic cavemen have revealed evidence of atherosclerosis (the hardening of the arteries that can be a precursor to a heart attack). So while it’s almost certainly true that fewer people suffered heart attacks in the 1800s than the 1900s (autopsies from the time, for example, do confirm fewer instances of heart disease), there were likely cardiac events that were not diagnosed due to lack of diagnostic tools and a different understanding of disease. To put a finer point on it: in 1850 if Grandpa died in his sleep, he had died of old age. In 1950 if he died in his sleep, it was presumed due to a cardiac arrest.
The next question that stems to mind from this argument is this: if there truly was more heart disease in the 1900s than the 1800s – in other words, it’s not just that doctors started diagnosing more heart disease, but that heart disease really did become more common – how much of this is simply a function of people living longer? This too is a nuanced topic. A person born in 1850 might have died at age 30 of Pneumonia, Tuberculosis, or Syphillis, but a similar person born in 1950 who got one of those disease at age 30 would be successfully treated for it with antibiotics, and might go on to live to 2010, when, at age 60, they suffered a fatal heart attack. This factor certainly accounts for a large portion of the rise of heart disease, as well as other “diseases of civilization” such as cancer and dementia. These diseases simply become more common with advancing age, and so a population that has a lot more old people in it is going to suffer a lot more from these diseases.
With that said, it also has to be understood that life expectancies are based on AVERAGES, and in pre-modern times an astronomically high number of children died in infancy, which brought the population average life expectancy way down. To make the point clearer: if two girls are born in the same year, and one dies during their first year of life and the other lives to be 80, the average life expectancy between them is 40 years old, but neither in fact died anywhere near age 40. So while life expectancy prior to the year 1900 was often in the 30s or lower, there were plenty of people in centuries past living into their 60s, 70s, and 80s.
Putting what I’ve written so far together, the fact that we have much more heart disease in modern times than we did prior to the year 1900 is at least in part an illusion: people are living longer, and hence living to an age where they get heart disease, and are doing so in an era when doctors have the know-how and tools to diagnose someone as having heart disease rather than attributing their symptoms to other conditions. When accounting for both of these factors, the rise in heart disease is not quite as stark as it appears upon first glance.
And yet, while all of the above is true, it seems that there really has been a rise in heart disease over the past century or so, such that if we could create an experiment in which we looked only at elderly people in the year 1800 using our modern diagnostic processes, we would indeed find there is more cardiac disease now than back then. I think that most doctors and scientists agree with this idea, and it’s on this final point where things get much more scientifically interesting. What accounts for the fact that, even adjusting for older age and better diagnosis, we probably really have experienced a rise in heart disease over the past century?
There are no end of theories about the topic, and this debate may never be settled. The main idea spun by mid 20th century doctors was that a higher standard of living led to an increased consumption of animal products, which in turn drove cholesterol levels up, leading to more heart disease. While this is somewhat plausible I think the “cholesterol skeptics” have a good case to make here. Consumption of red meat, eggs, bacon, butter, etc were not in fact that rare in wealthier countries such as the United States, Canada, and the UK during the 1800s. Perhaps Americans of the 1950s consumed more of these items than their counterparts from a century prior, but it’s worth remembering that the typical American of say the pre-Civil War days lived on a farm and in fact had access to quite a few animal based foods in their diet. Furthermore, bottled vegetable oil widely available at the grocery store just wasn’t a thing, so even when eating non-animal foods such as oats or vegetables, they were mostly cooked in animal fats like tallow, lard, and butter.
Moreover, a LOT of things changed in the 20th century as living standards increased. To name just a few:
Cigarette smoking became widespread
More people began working office jobs, using cars, and in other ways being a lot more sedentary
The electrification of the country allowed people to, for the first time in history, disrupt the normal circadian rhythm of life by staying up late into the evening, and staying indoors and avoiding sunlight much of the day
Sugar consumption exploded
Processed foods went from being almost non-existent to being the main source of caloric intake for the average American
Industrial seed oils, and their especially evil twin, hydrogenated oils, were invented and entered the food supply en masse
The advent of antibiotics, modern sanitation and sterile birth techniques – while dramatically reducing death from infection and extending life expectancy – also started to change our gut microbiomes
Pollutants from industrial processes entered our air and water in huge number
I could probably think of a hundred more items, so I’ll stop there. The point of this all being that, in one sense, the rise of cardiovascular disease is a sign of our success as a society. We live longer and have better medical care than our ancestors could ever have dreamed of. But in another way the rise of cardiovascular disease (and other diseases) is likely due to a wide myriad of changes in the way we live. Which makes it a bit suspect to claim that the most salient reason Americans of the 20th century started dying of cardiovascular disease in record numbers was simply due to a high fat diet and high cholesterol.
Finally, let me close this post out with some good news: in the United States, the rate of death from cardiovascular disease in fact peaked in 1968, and has declined quite a bit since. It’s still the number one killer, but we are actually suffering its effects less than our grandparents did. The most likely explanation for this is that the mid 1960s were precisely the time that attitudes around smoking began to change, and a reduction in heart attacks followed as Americans started curtailing their cigarette consumption.
Another important reason for the decline is the huge improvement in medical treatment with advanced diagnostic techniques, stents, coronary bypass surgeries, and a whole slew of medications that have entered the market from the 1960s onward. So even though too many Americans still die of heart attacks, we’ve really succeeded in turning the majority of heart attacks into survivable events. This is one of those great triumphs of modern medicine, and an area where we should actually be grateful to some of the advances that big pharma and big medicine have brought to us. While I continue to favor lifestyle, prevention, and a holistic approach as the cornerstone to good health, I am never opposed to ALSO taking advantage of the best that pharmaceutical and medical technology have to offer us.
