There are many guidelines on how to live to lessen your chance of a heart attack. It’s common knowledge that avoiding things like red meat, fatty foods, and smoking are better for your heart. Exercising and staying active is good for your heart. But many people make poor choices for decades without having a heart attack They may live their whole life smoking, eating red meat daily, and being sedentary, yet they don’t have a heart attack until they are 60+. Why does it take decades for something like eating an artery-clogging diet to finally clog up the arteries enough to have a heart attack?
And on the flip side, how dangerous is it for a previously fit and healthy person to start making unhealthy choices after 60? If a vegetarian who runs marathons decides at 60 to sit on the couch, eat fatty steaks, and smoke heavily, will it produce any significant difference to his heart attack risk? Will he need to have bad habits for decades before risking a heart attack?
One cigarette doesn’t do much damage. But a pack a day for 40 years is 292,000 cigarettes, which eventually inflicts enough damage to set the stage for a premature death. The situation is similar for cheeseburgers and couch surfing.
I would expect it to happen sooner because decades years seems like a very long time. Do arteries really clog that slowly? Does eating 2 cheeseburgers a day for 60 years only add a 1/60th of a layer of gunk per year to the artery? That seems like almost nothing. I’ve had house plumbing that gets clogged in a couple of years. The very slow progression of heath issues leading to a heart attack seems almost too slow. I’m wondering if there’s something else going on that magnifies the effect after a certain age. So maybe unlimited cheeseburgers before you’re 30 have little effect, but then after that your body can’t handle it and problems start to form.
The body is a tough and - at times - unpredictable machine. In my job I regularly deal with people who are poster children for unhealthy lifestyles - obese, sedentary smokers and drinkers with horrible diets and horrible genetics. But some of them just keep staggering on, while other ostensibly healthy folk drop dead while jogging. Go figure. Healthy choices can tilt the odds, but are not predictable for any specific case.
Some people with unhealthy lifestyles *never *have a heart attack. Lifestyle is a risk factor but genetics play a significant role.
Comparing coronary arteries to house plumbing is a flawed analogy. A lot of what clogs arteries is cholesterol manufactured by your liver. Certain foods can increase this, like trans fats, but it’s not like there is a stream of cheeseburger fat running through your arteries.
For someone who has clogged arteries when they are 60, what would you expect their arteries to have looked like throughout their life, assuming they kept the same lifestyle the whole time? Would you find them slightly clogged in their 20’s, a little more in their 30’s, etc. until they are fully clogged in their 60’s? Or would the early years be relatively clear until some point when they’re older and then they rapidly clog?
I wouldn’t say they’re slightly clogged in their 20s, because “clogged” implies that there is a some blockage. But plaque can begin developing in childhood and it doesn’t necessarily build up evenly in all of the arteries - I have a stent in one artery but the others were not as blocked and didn’t need stents. Oh and even then, I didn’t have any symptoms. It was a completely different issue that sent me to the cardiologist to begin with - and after seeing him for a couple of years, I had an abnormal stress test.
It has to do with genetics. There are some young people who do have heart attacks due to coronary artery disease due to “bad genes.” Compared to the overall population of people who have heart attacks due to CAD, however, they are only a small percentage. The issue is that the human body doesn’t merely wear down due the passage of time the way a mechanical device does. Instead our bodies our programmed to degenerate with the passage of time in a process that starts in our late teens / early 20s. Older arteries are more prone to damage from bad lifestyles due to this programmed senescence. A few unfortunate people do have genes that contribute to earlier onset heart disease, whether these be genes that cause defects in metabolizing cholesterol, causing the walls of arteries to become stiffer at an earlier age, genes that cause platelets or clotting factors to be more likely to form clots and block off circulation, etc. For the most part, however, it’s due to the older body being more prone to damage from a bad lifestyle than the younger body because of the effects of aging.
My son in law had his first heart attack at 37. He still eats crap and smokes. His wife said he would be lucky to see fifty. He’s going to make it, today is his 50th birthday.
One aspect to consider is that what goes into and stay in your bloodstream is carefully regulated and monitored. It’s not a perfect system, but if you eat just lardo for a day your digestive system is not going to put lumps of pork fat into your veins, it’s going to deliver various soluble end products of the digestive processes for fat.
Now some of those end products may interact in a negative manner, depending on your other diet, your genetics, your activity level, etc, but it’s a slow process, because we’re not talking about dealing with something inherently bad for you, we’re talking about excessive amounts of stuff that the body is perfectly capable of handling quite a lot of.
Relevant to this discussion: a newly published paper by an international panel reviewing a host of studies on red meat and effects on health has controversial conclusions:
*"In one review of 12 trials with 54,000 people, the researchers did not find statistically significant or an important association between meat consumption and the risk of heart disease, diabetes or cancer.
In three systematic reviews of cohort studies following millions of people, a very small reduction in risk among those who had three fewer servings of red or processed meat a week, but the association was uncertain."*
Others are challenging the study’s findings.
In regards to the OP’s question, it takes time for serious cardiac effects (i.e. from diet or lifestyle choices like smoking) to manifest. Eventually a tipping point is reached.
My father had his first heart attack at age 43 after a lifetime of smoking. He didn’t stop smoking and had his second and fatal attack 20 years later. I had my first (and only) heart attack at 28, after maybe 13 years of smoking. Never touched another cigarette. That was 54 years ago. I am not and never was especially careful of my diet, although I don’t drink soda or eat junk foods.
The root cause of heart disease is aging (unless you have terrible genetics, and luckily most people do not).
We’ve invented this philosophy that a perfect lifestyle can avert death as a form of death denialism, but the reality is aging kills us all given enough time. All lifestyle does is moderately accelerate or moderately delay the effects of aging. Point is, unless you have horrible genetics the root cause of things like heart diseases, stroke, dementia, etc is aging. Lifestyle is a minor factor compared to aging.
Poor lifestyle increases your risk of a heart attack by something like 50-100%. Getting older increases the risk by 10,000% or more.
It’s also evolved to be an over-specced machine. There are lots of parts of the body that have excess capacity beyond what is needed.
Besides all the body parts that have a built-in spare (2 each of lungs, kidneys, breasts, ovaries/testicles, etc.), many organs like the liver, pancreas, lungs are over sized. Thus, for example, many liver diseases aren’t caught until more than half of the liver has been damaged, and symptoms become obvious. Which makes them more dangerous, because when they are caught, it may be too late for the doctors.
If the body had been designed like a machine, much of this over-capacity would be eliminated as wasteful and inefficient. But the semi-accidental nature of evolution has kept these around.
Of course, many of the problems from unhealthy lifestyles don’t matter to evolution – they appear when the person has already passed out of reproductive age.
As a few have pointed out, while multiple factors taken together determine one’s risk, the biggest single factor is genetics. Let’s look at cholesterol, for example. We know now that eating cholesterol is not the evil killer it had been vilified as for so many years.
No, what is exponentially more predictive is your natural bodily cholesterol levels. The body, when it’s working right (I’d appreciate correction on this statement if wrong) has an amazing system of balancing levels of cholesterol produced by the body along with the levels consumed in diet, in order to maintain a stable, safe overall cholesterol level. If you consume less cholesterol, you body will produce more. And if you consume more, less is produced by the body. But people vary widely on their “set points” for natural cholesterol levels. And i would assume having abnormally high levels in the body has a negative affect on the body’s ability to stay in healthy balance. Because that “balance point” itself, is unhealthy. But if you have a normal cholesterol level, eating a three egg omelet every morning will not (right?) elevate your numbers significantly, if at all.
Unfortunately, that is the sad truth about aging. But living a healthy life does seem to have some benefits. Take someone like Jack LaLanne. He lived a very healthy lifestyle, ate a vegetarian diet and exercised hours every day of his life. He made it all the way to 96! Compare that to someone like George Burns. He smoked a dozen cigars a day for decades but only made it to 100. Ummm, wait a minute …
The meta-answer to this is: because if it were otherwise our species would be extinct.
We’re evolved to last past child rearing age while eating any old crap. Because often in history any old crap was all that was available. A metabolism that can in theory subsist off whale eat and no green veggies for nine months a year, or 99% barley meal and turnips, is going to laugh in the face of “you have red meat more than five meals a week - that’s unhealthy”
A very famous study, I believe of Korean War soldiers KIA, showed that early traces of atherosclerosis were quite common even in robust 20 year olds. This gave rise to the idea that it takes decades (usually) for atherosclerosis to run its course to the point of a heart attack, or stroke, etc.
Still, even when atherosclerotic blockages and narrowings in the arteries are already mature and established, both lifestyle interventions as well as cholesterol-lowering medications can lead to the blockages becoming less likely to suddenly clot off and cause a heart attack. It is the sudden cutting off of blood flow (usually at the site of an established narrowing or partial blockage) that causes the heart attack.
The most interesting data (to me at least) is that even long-term heavy smokers who quit will see their rate of heart attacks become indistinguishable from never-smokers after only a few years of abstinence. This points out that it’s not just the blockages and narrowing that lead to heart attacks (because they persist) but rather it’s the sudden clotting off of blood flow at the site of a pre-established blockage that does it. And whereas the tendency for arteries to suddenly clot off is enhanced by current smoking, it begins to fade soon after quitting and disappears after a few years.
In contrast, smokers who stop smoking will never see their lung cancer rates drop to those of never-smokers. They remain quite high forever.
Healthy lifestyle will delay the onset of chronic disease and increase your health span and lifespan. But probably only by a decade or so max.
So if you lead a poor lifestyle, you’ll die from complications of old age in your 70s. If you lead a healthy lifestyle you’ll die from complications of old age in your 80s.