# What causes heart attacks? **URL:** \ **Category:** Factual Questions\ **Created:** [July 28, 2010, 2:38am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259 "2010-07-28T02:38:42Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![kim\_jung\_il](https://avatars.discourse-cdn.com/v4/letter/k/54ee81/32.png) [@kim\_jung\_il](https://boards.straightdope.com/u/kim_jung_il)\ **Post date:** [August 3, 2010, 1:20am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/41 "2010-08-03T01:20:33Z")
As a side issue (but a relevant one), I once met a woman at a hospital who was visiting her husband. The husband was in an advanced stage of stomach cancer. The doctor had told him that the reason he had developed this cancer was because he had lived too well. He ate very healthily, he exercised a lot, he did not smoke or drink either. Seemingly, looking after yourself too well is just as bad for you as not looking after yourself. ---
**Author:** ![Shmendrik](https://avatars.discourse-cdn.com/v4/letter/s/ee7513/32.png) [@Shmendrik](https://boards.straightdope.com/u/Shmendrik)\ **Post date:** [August 3, 2010, 1:39am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/42 "2010-08-03T01:39:05Z")
> [@kim\_jung\_il](#): > > As a side issue (but a relevant one), I once met a woman at a hospital who was visiting her husband. The husband was in an advanced stage of stomach cancer. The doctor had told him that the reason he had developed this cancer was because he had lived too well. He ate very healthily, he exercised a lot, he did not smoke or drink either. > > Seemingly, looking after yourself too well is just as bad for you as not looking after yourself. Risk factors for stomach cancer include tobacco and alcohol use. I suspect the woman and/or her husband misunderstood the doctor. ---
**Author:** ![Angel\_of\_Doubt](https://avatars.discourse-cdn.com/v4/letter/a/7cd45c/32.png) [@Angel\_of\_Doubt](https://boards.straightdope.com/u/Angel_of_Doubt)\ **Post date:** [August 3, 2010, 3:00am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/43 "2010-08-03T03:00:33Z")
> [@Surreal](#): > > [QUOTE=AHA] > **Select fat-free, 1 percent fat, and low-fat dairy products.** > So if you follow the AHA’s advice and consume low-fat dairy products instead of the full-fat varieties, you’ll be more THREE TIMES more likely to drop dead from heart disease. > > Great advice! Better pour some skim milk on your Cocoa Puffs… Goodness. Great stuff, **Surreal.** Have fun with GCBC, **Grateful Un-Dead**. Better pamper a few brain neurons, it’s quite a heavy read. ---
**Author:** ![Grateful-UnDead](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@Grateful-UnDead](https://boards.straightdope.com/u/Grateful-UnDead)\ **Post date:** [August 3, 2010, 8:00am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/44 "2010-08-03T08:00:19Z")
OK. Now that we have dropped the hand grenade into the diet theory, how about exercise? Is there any credible, fact based, evidence that exercise is good for you? By this I mean to ask whether exercise will either keep you healthy or restore your health. (I define “healthy” as the absence of any pathological condition; and “fit” as the capacity to do physical work.) I ask this in the context that I had every reason to believe I was both healthy, and fit; right up until I woke up in the ICU having suffered a heart attack. This despite the fact that since my early teenage years I ran an average of 30 miles per week, and occasionally did a workout in the gym. So is there any credible evidence that sitting on the couch watching TV all the time is any less healthy than running 30 miles per week? ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [August 3, 2010, 4:24pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/45 "2010-08-03T16:24:26Z")
> [@Grateful-UnDead](#): > > I ask this in the context that I had every reason to believe I was both healthy, and fit; right up until I woke up in the ICU having suffered a heart attack. This despite the fact that since my early teenage years I ran an average of 30 miles per week, and occasionally did a workout in the gym. > > So is there any credible evidence that sitting on the couch watching TV all the time is any less healthy than running 30 miles per week? Well, since I’ve already shown that following the AHA diet can kill you and that low-fat dairy products are much more likely to kill you than the full-fat varieties, I might as well round everything off by showing that running can kill you as well: > **[Myocardial late gadolinium enhancement: prevalence, pattern, and prognostic...](https://pubmed.ncbi.nlm.nih.gov/19332846/?itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum&ordinalpos=1)** > > Ostensibly healthy marathon runners have an unexpectedly high rate of myocardial LGE, and this may have diagnostic and prognostic relevance. > [@](#): > > RESULTS: Of the 102 runners, five had a CAD pattern of LGE, and seven had a non-CAD pattern of LGE. The CAD pattern of LGE was located in the territory of the left anterior descending coronary artery more frequently than was the non-CAD pattern (P = .0027, Fisher exact test). **The prevalence of LGE in runners was higher than that in age-matched control subjects (12% vs 4%; P = .077,** McNemar exact test). The event-free survival rate was lower in runners with myocardial LGE than in those without myocardial LGE (P \< .0001, log-rank test). CONCLUSION: **Ostensibly healthy marathon runners have an unexpectedly high rate of myocardial LGE, and this may have diagnostic and prognostic relevance** Note that LGE is considered the “gold standard” for determining cardiovascular disease. What’s funny here is that runners are generally very into health and fitness (they tend to eat healthy diets, they don’t smoke, they aren’t overweight, etc.) but they still ended up THREE TIMES more likely to have heart disease than controls who basically sat on their asses all day. As you can see, the conventional wisdom on virtually all matters related to health/nutrition/fitness is often unsupported by science and/or completely wrong. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 3, 2010, 6:47pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/46 "2010-08-03T18:47:52Z")
> [@](#): > > RESULTS: Of the 102 runners, five had a CAD pattern of LGE, and seven had a non-CAD pattern of LGE. The CAD pattern of LGE was located in the territory of the left anterior descending coronary artery more frequently than was the non-CAD pattern (P = .0027, Fisher exact test). **The prevalence of LGE in runners was higher than that in age-matched control subjects (12% vs 4%; P = .077,** McNemar exact test). The event-free survival rate was lower in runners with myocardial LGE than in those without myocardial LGE (P \< .0001, log-rank test). CONCLUSION: **Ostensibly healthy marathon runners have an unexpectedly high rate of myocardial LGE, and this may have diagnostic and prognostic relevance** > > Note that LGE is considered the “gold standard” for determining cardiovascular disease. > > What’s funny here is that runners are generally very into health and fitness (they tend to eat healthy diets, they don’t smoke, they aren’t overweight, etc.) but they still ended up THREE TIMES more likely to have heart disease than controls who basically sat on their asses all day. > > As you can see, the conventional wisdom on virtually all matters related to health/nutrition/fitness is often unsupported by science and/or completely wrong. Come on, now. There’s no need to cherry pick, especially when the study you cite doesn’t prove much except that older marathon runners (who may well have picked up the hobby as a result of prior heart problems or because of concern of same) have a **non-significantly increased** prevalence of GAD-MR abnormalities (which were presumably asymptomatic since these people were runners. Then again, if they _were_ symptomatic, then such abnormalities aren’t unexpected, are they?) No, all this single, small study shows is that unselected marathon runners can have occult heart disease. But the question remains, on the basis of this study, at least, whether runners on average have more or less heart disease than non-runners. This study didn’t answer that question showing as it did only a non-significant result, again looking at runners who may have taken up the sport as a _result_ of having heart disease (or perhaps risk factors for it). OTOH, [this recent free, full text review from the Mayo Clinic Proceedings](http://www.mayoclinicproceedings.com/content/84/4/373.long), summarizes the overwhelming evidence that exercise (i.e. physical activity and fitness) protects against both the development and progression of heart disease. ---
**Author:** ![rhubarbarin](https://avatars.discourse-cdn.com/v4/letter/r/eb9ed0/32.png) [@rhubarbarin](https://boards.straightdope.com/u/rhubarbarin)\ **Post date:** [August 3, 2010, 7:08pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/47 "2010-08-03T19:08:19Z")
Eating what the Food Pyramid dictates is a recipe for chronic pain and disease. Running 30 miles per week is an additional strain on your body. Not that exercise hasn’t been shown to confer some benefits on health and longevity. But we’re talking ‘moderate’ exercise and fitness levels (defined, usually, as brisk walking for 30 minutes daily or equivelant). There’s no evidence that the more exercise you do the better, and excessive cardio exercise, besides being tentatively linked to heart issues, has also been linked to reduced muscle mass and bone density (both of which are correlated with reduced longevity and health), and joint injuries and arthritis (which have negative effects on mobility, muscle mass, and bone density). ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [August 3, 2010, 7:20pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/48 "2010-08-03T19:20:11Z")
> [@KarlGauss](#): > > Come on, now. There’s no need to cherry pick, especially when the study you cite doesn’t prove much except that older marathon runners ( **who may well have picked up the hobby as a result of prior heart problems or because of concern of same** ) have a **non-significantly increased** prevalence of GAD-MR abnormalities (which were presumably asymptomatic since these people were runners. Then again, if they _were_ symptomatic, then such abnormalities aren’t unexpected, are they?) The study looked at "102 ostensibly healthy male runners ", not people that had already suffered heart attacks. Do you seriously think that significant numbers of people that have actually had heart attacks take up running marathons, and that the study authors didn’t control for this by asking the participants about their medical history? Seems pretty outlandish to me. > [@KarlGauss](#): > > OTOH, [this recent free, full text review from the Mayo Clinic Proceedings](http://www.mayoclinicproceedings.com/content/84/4/373.long), summarizes the overwhelming evidence that exercise (i.e. physical activity and fitness) protects against both the development and progression of heart disease. The OP asked about running 30 miles per week, which I think puts him into roughly the same activity category in the Breuckmann study. The studies you cite talk about much more moderate exercise activities (such as walking 0.5 miles a day, being a more “active” switchman, etc.). Perhaps running a marathon strains the heart in a way that is harmful, but walking a few miles here and there doesn’t? ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [August 3, 2010, 7:37pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/49 "2010-08-03T19:37:11Z")
Here’s another article you might find interesting: > **[ACC: The Agony of Long-Distance Runners -- Coronary Plaque](https://www.medpagetoday.com/meetingcoverage/acc/19091)** > > ATLANTA -- A group of elite long-distance runners had less body fat, better lipid profiles, and better heart rates than people being tested for cardiac disease, but, paradoxically, the runners had mor > [@](#): > > Investigators performed computed tomography angiography on 25 people who had run at least one marathon a year since 1985, according to senior author Robert Schwartz, MD, of the Minneapolis Heart Institute and Foundation. They compared the athletes with 23 control patients who were undergoing the same scan for symptomatic or suspected heart abnormalities. > > **In controls, the calcium plaque volume was 169 mm3 compared with 274 mm3 for the elite runners (P=0.028)**, the researchers reported at the American College of Cardiology meeting. The runners also had a higher calcium score and higher noncalcified plaque volume, although those differences did not reach statistical significance. Small study, but the runners actually had more plaque than people who already had existing cardiovascular symptoms. ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [August 3, 2010, 8:01pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/50 "2010-08-03T20:01:09Z")
> **[Science & Tech Archives — Harvard Gazette](https://news.harvard.edu/gazette/section/science-technology/)** > [@](#): > > **Cardiovascular risks seen from marathon running** > > **Researchers analyzed the blood of marathon runners less than 24 hours after they had finished a race. They found abnormally high levels of inflammatory and clotting factors of the kind that are known to set the stage for heart attacks**. “My concern is for people who exercise thinking ‘more is better,’ and that marathon running will provide ultimate protection against heart disease,” said Arthur Siegel, director of Internal Medicine at McLean Hospital in Belmont, Mass., and an assistant clinical professor of medicine at Harvard Medical School. “In fact, \*\*it can set off a cascade of events that may transiently increase the risk for acute cardiac events.” \*\* ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 3, 2010, 8:06pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/51 "2010-08-03T20:06:53Z")
I’m not saying that runners don’t get heart disease. Hey, Jim Fixx dropped dead with an MI while jogging. And nor am I saying that the more exercise you do, the better. Nope, I just want to emphasize is that physically active, fit people have less heart disease (and less diabetes, hypertension, etc.) than their sedentary counterparts. ---
**Author:** ![Grateful-UnDead](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@Grateful-UnDead](https://boards.straightdope.com/u/Grateful-UnDead)\ **Post date:** [August 4, 2010, 12:19am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/52 "2010-08-04T00:19:30Z")
Oh my God!!! Before I go down into the basement and shoot myself… Is there any general benefit from exercise, other than that related to heart disease?? Please, please don’t tell me that I should have spent my life sitting on the couch eating pizza and drinking beer …! ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 4, 2010, 2:17am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/53 "2010-08-04T02:17:58Z")
> [@Grateful-UnDead](#): > > Is there any general benefit from exercise, other than that related to heart disease?? I hope I won’t be too vigorously challenged by stating that regular exercise is associated with protection from or benefit with respect to: - coronary heart disease (“heart attacks”) - diabetes (better control in, and prevention of the development of type II diabetes) - hypertension (high blood pressure) - breast and colon cancer (maybe others) - osteoporosis - COPD (emphysema et al) Looking at things from a slightly different angle, exercise is also associated with decreased mortality in people with hypertension, COPD, diabetes, smoking, and obesity. So, for example, for the same high blood pressure or number of cigarettes smoked, the person who exercises will live longer. But why listen to me? Here is a very readable, relatively recent, free, full-text review entitled, “[Health Benefits of Physical Activity: The Evidence](http://www.cmaj.ca/cgi/content/full/174/6/801)”. What more could you ask for? 😉 If nothing else, read the section titles, and look at the figures. (BTW, the article requires that you know that “primary prevention” means preventing the disease in the first place, whereas “secondary prevention” means trying to treat the disease, or prevent its progression or recurrence, once it’s already developed, e.g. preventing another heart attack in a heart attack survivor) ---
**Author:** ![rhubarbarin](https://avatars.discourse-cdn.com/v4/letter/r/eb9ed0/32.png) [@rhubarbarin](https://boards.straightdope.com/u/rhubarbarin)\ **Post date:** [August 4, 2010, 3:19am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/54 "2010-08-04T03:19:36Z")
I spent some time with PubMed earlier today. I couldn’t find a single study that _didn’t_ conclusively find that having the highest levels of moderate (defined as brisk walking or equivalent) and vigorous activity was correlated with better longevity and improved general health including all the specific conditions **KarlGauss** mentioned above. People who only do ‘light’ activities or are sedentary have the worst outcomes by far. I think it’s absolutely healthy and important to be active. Thanks for the last link **KarlGauss** , could have saved me some time! ---
**Author:** ![Surreal](https://avatars.discourse-cdn.com/v4/letter/s/eada6e/32.png) [@Surreal](https://boards.straightdope.com/u/Surreal)\ **Post date:** [August 4, 2010, 6:30pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/55 "2010-08-04T18:30:48Z")
> [@KarlGauss](#): > > > [@Grateful-UnDead](#): > > > > . . . taking cholesterol lowering drugs, in fact, increase your chance of having a heart attack . . . > > This is simply not the case. **Many, high quality research studies have shown the exact opposite - lowering cholesterol reduces your chance of having a heart attack.** I don’t think this has been shown in ANY study, at least none that I’m aware of. What the studies have shown is that taking statins reduces your chance of having a heart attack, but statins have a MYRIAD of effects on the body, some beneficial (reduced inflammation), some not (reduced co-enzyme Q10). It’s entirely possible that something effect of the drugs (other than the cholesterol-lowering) is responsible for the reduction in heart attacks. Dr. Uffe Raviskov elaborates here: [http://www.ravnskov.nu/myth6.htm](http://www.ravnskov.nu/myth6.htm) > [@](#): > > Have these trials really demonstrated that raised LDL cholesterol has importance for coronary heart disease, as the trial directors concluded in the reports? > > There is reason to question that, because some of the results are not consistent with what we have learned about cholesterol. > > First, old patients were protected from cardiovascular disease just as much (or as little) as young ones, although most studies have shown that a high cholesterol is a weak risk factor, or no risk factor at all, for old people. (Unfortunately, in the only trial that included old people only, the PROSPER trial, the lowering of heart mortality was smaller thanm the increse of cancer mortality). > > Second, also the number of strokes was reduced after statin treatment, although no studies have shown that a high cholesterol is a risk factor for stroke. > > Third, patients who had had a coronary were protected although most studies have shown that a high cholesterol is a weak risk factor, if any at all, for those who already have had a coronary. (In fact, this finding should have stopped all the previous, secondary preventive trials). > > And finally, the statins protected against coronary heart disease whether the cholesterol was high or low although most studies have shown that a normal or low cholesterol is no risk factor for coronary disease. ---
**Author:** ![KarlGauss](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/karlgauss/32/3713_2.png) [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)\ **Post date:** [August 4, 2010, 11:25pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/56 "2010-08-04T23:25:22Z")
> [@Surreal](#): > > It’s entirely possible that something effect of the drugs (other than the cholesterol-lowering) is responsible for the reduction in heart attacks. Possibly, but other cholesterol lowering drugs (i.e. cholestyramine, niacin) have also been shown to reduce heart attacks. Especially in light of cholestyramine doing little else but lowering cholesterol, the fact that they all have in common a reduction in cholesterol (LDL) is compelling. More convincing (IMO) are the “experiments of nature”: people with sky-high cholesterol levels from familial hypercholesterolemia _will_ have heart attacks, often before puberty(!) However, after liver transplantation, these same people, whose problem was a single gene mutation, experience profound reduction in cholesterol and, in turn, reduced atherosclerosis. [Here’s a neat report about the first case - Stormie Jones](http://www.nejm.org/doi/full/10.1056/NEJM198412273112603) (although this one doesn’t document regression of coronary disease, others do). I’m not saying it’s the only, or the major, reason for coronary disease, but in some people, cholesterol lowering works to reduce coronary disease. And, as I noted upstream, the more usual clinical trials have consistently demonstrated reduced atherosclerosis by lowering cholesterol (yes, only a small percentage of people taking the drugs benefit, but the effect is real. And reproducible). ---
**Author:** ![Grateful-UnDead](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@Grateful-UnDead](https://boards.straightdope.com/u/Grateful-UnDead)\ **Post date:** [August 5, 2010, 3:53am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/57 "2010-08-05T03:53:19Z")
In light of what we have learned so far with regard to heart disease and diet, I strongly recommend that everybody view this YouTube video. [![](https://img.youtube.com/vi/KTKysI59HAw/hqdefault.jpg "Heart Attack Grill - Extreme Pigouts") ](https://www.youtube.com/watch?v=KTKysI59HAw) Definitely something that could make life worth living. ---
**Author:** ![rhubarbarin](https://avatars.discourse-cdn.com/v4/letter/r/eb9ed0/32.png) [@rhubarbarin](https://boards.straightdope.com/u/rhubarbarin)\ **Post date:** [August 5, 2010, 12:14pm UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/58 "2010-08-05T12:14:00Z")
Mm, ground beef fried in lard with cheese. I admit I have this all the time (without a bun), it is pretty great. ---
**Author:** ![Grateful-UnDead](https://avatars.discourse-cdn.com/v4/letter/g/ccd318/32.png) [@Grateful-UnDead](https://boards.straightdope.com/u/Grateful-UnDead)\ **Post date:** [August 9, 2010, 1:45am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/59 "2010-08-09T01:45:01Z")
Over the weekend, I read both the papers by Warburton et al and Mente et al, referred to in posts above. Both make fascinating reading, particularly since they seem to suggest that many of the public health assertions we are bombarded with are apparently in contradiction to the empirical evidence. This got me to thinking about other related issues: specifically, What is the evidence regarding salt? Is it really the poison of the Devil? Or is it a victim of misinformation? How about “fast food” and “junk food”. Are they just victims of bad press, or is there really some scientific basis for their pariah status? ---
**Author:** ![needscoffee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/needscoffee/32/1076_2.png) [@needscoffee](https://boards.straightdope.com/u/needscoffee)\ **Post date:** [August 9, 2010, 2:37am UTC](https://boards.straightdope.com/t/what-causes-heart-attacks/548259/60 "2010-08-09T02:37:18Z")
> [@Grateful-UnDead](#): > > Over the weekend, I read both the papers by Warburton et al and Mente et al, referred to in posts above. > > Both make fascinating reading, particularly since they seem to suggest that many of the public health assertions we are bombarded with are apparently in contradiction to the empirical evidence. > > This got me to thinking about other related issues: specifically, > > What is the evidence regarding salt? Is it really the poison of the Devil? Or is it a victim of misinformation? > > How about “fast food” and “junk food”. Are they just victims of bad press, or is there really some scientific basis for their pariah status? All of this is covered in **Good Calories, Bad Calories**. Taubes has something like 100 pages of end notes referencing studies he re-evaluated. Basically, salt = victim of misinformation; carbs are the problem. Carbs cause insulin and insulin-related growth factor to be released, both of which seem to be driving most of the problems in metabolic syndrome, as well as growth of tumors which are estrogen-dependent, such as breast and colon cancers, whose tumors have far more insulin receptors than ordinary tissue. [Previous page](https://boards.straightdope.com/t/what-causes-heart-attacks/548259.md?page=2) [Next page](https://boards.straightdope.com/t/what-causes-heart-attacks/548259.md?page=4)