Heart disease was once the inevitable, unpredictable killer that took down even the most powerful people on Earth with no warning and almost no treatment. Decade by decade, researchers identified the specific, modifiable risk factors behind it — and the story of how that happened, from a president’s heart attack in 1955 to a lizard’s venom to a broken gene, explains why heart attacks are becoming far more preventable than they used to be. (Based on the insights of Dr. Brad Stanfield)
Key Takeaways
- Heart attack risk factors — smoking, blood pressure, diet, obesity/diabetes, and cholesterol — were identified one at a time over 70 years of trials, starting with President Eisenhower’s 1955 heart attack.
- GLP-1 weight-loss drugs, discovered via Gila monster venom research, now have trial evidence (the SELECT trial) directly showing they reduce heart attacks and strokes, not just weight.
- Genetic studies of people born with naturally lower cholesterol (via PCSK9 variants) show dramatically less heart disease with no other lifestyle differences — strong evidence that lowering LDL/apoB genuinely reduces risk.
- Aggressively lowering cholesterol has been directly tested for cognitive harm and found not to cause it — statins have even been linked to lower, not higher, dementia rates in large studies.
- A new once-daily oral PCSK9 inhibitor (enlicitide, brand name Lipfendra), approved July 2026, lowers LDL by roughly 56-59% without needing injections.
The Turning Point: A President’s Heart Attack
In September 1955, U.S. President Dwight Eisenhower suffered a heart attack while in office. At the time, medicine had little to offer beyond an oxygen tent, morphine, a handful of other drugs, and nearly seven weeks of bed rest. What changed the public conversation wasn’t the treatment — it was that his cardiologist, Dr. Paul Dudley White, stood in front of reporters and explained that heart attacks might have identifiable causes, like diet, alcohol, tobacco, exercise, and family history. At the time, that was a genuinely novel idea. It would still take decades of research to work out which risk factors actually mattered, and heart disease rates didn’t meaningfully turn around until well into the 1960s.
Risk Factor by Risk Factor
Smoking
American cigarette consumption peaked in 1963. The following year, the U.S. Surgeon General’s report formally tied smoking to heart disease, and consumption fell immediately and never recovered — by 2011, the average American adult smoked about 72% less than in 1963. Heart attack rates declined alongside smoking rates. But plenty of people who never smoked still had heart attacks, so smoking alone couldn’t explain the full picture.
Blood Pressure
The Framingham Heart Study, which began collecting health data on roughly 5,000 residents of one town in 1948, found that high blood pressure carried more than twice the risk of coronary heart disease in middle-aged men. But Framingham was observational — it could show that blood pressure and heart disease risk moved together, not that lowering blood pressure actually helped. That answer came from a 1967 Veterans Administration trial in which men with severely elevated blood pressure were randomized to blood-pressure-lowering drugs or a placebo. The trial had to stop early: there were 27 severe complications in the placebo group compared to just two in the treatment group.
More recent trials have refined how low blood pressure targets should go. The SPRINT trial, involving over 9,000 people, found that aiming for a systolic (top number) blood pressure below 120 — compared to around 140 — reduced cardiovascular events by about a quarter and overall deaths by 27%. A few caveats: blood pressure should be measured properly, ideally at home while relaxed, and frail patients or anyone prone to dizziness on standing may reasonably aim for a higher target.
Diet
The DASH trial found that a diet rich in fruits, vegetables, fiber, potassium, and low-fat dairy lowered systolic blood pressure by about 5.5 points compared to a control diet, an effect that grew to about 8.9 points when combined with reduced salt intake. Separately, the CORDIOPREV trial followed just over 1,000 people who already had coronary heart disease for 7 years, and found about 25% fewer heart disease events on a Mediterranean diet rich in unsaturated fats (olive oil, avocados, fish, nuts, seeds) compared to a low-fat diet.
Still, none of this fully explains the picture — plenty of people who don’t smoke, have well-controlled blood pressure, eat well, and exercise still have heart attacks.
An Unexpected Source: A Venomous Lizard
Obesity and diabetes rates climbed steadily over the following decades, and for a long time, no diet or exercise intervention reliably reversed this at a population level. The eventual breakthrough came from an unlikely direction: research into the venom of the Gila monster, a desert lizard capable of eating up to a third of its body weight in one meal and going months between meals while keeping its blood sugar remarkably stable. In 1992, researcher John Eng isolated a compound from Gila monster venom, called exendin-4, that was roughly half identical to the human hormone GLP-1 (which signals the pancreas to release insulin) — but unlike the human version, which breaks down within minutes, the lizard version lasted for hours.
The first GLP-1 drug, derived from this discovery, was FDA-approved in 2005. It required twice-daily injections and had modest effects. Each subsequent generation became more potent: once-daily liraglutide in 2010, once-weekly semaglutide in 2017, and eventually higher-dose formulations tested specifically for weight loss, where semaglutide (Wegovy) produced roughly 15% body weight loss — a level no earlier drug had reached.
For years, no weight-loss drug had been shown to actually prevent heart attacks, until the 2023 SELECT trial, which followed over 17,000 people with existing heart disease and elevated BMI (but no diabetes) for about 3 years. The semaglutide group had major cardiovascular events in about 6.5% of participants, compared to 8% on placebo — a relative reduction of roughly a fifth. Newer drugs have pushed weight loss further still: tirzepatide (which combines GLP-1 with a second gut hormone, GIP) produced up to 21% body weight loss at its top dose in trials, and retatrutide (which adds a third hormone, glucagon) produced up to roughly 30% body weight loss in its published phase 3 trial results. As a general pattern, blood pressure tends to fall by about one point for every kilogram of weight lost.
The Cholesterol Story
A separate line of research addressed a stubborn question: plenty of lean, non-diabetic people with good blood pressure, diet, and exercise habits still have heart attacks. In the 1990s, a research team in Paris studying French families with an inherited condition that causes sky-high cholesterol and early heart attacks discovered a new gene, PCSK9, that drives cholesterol levels up when overactive.
The reverse question turned out to be just as important: what happens when PCSK9 is naturally broken? These loss-of-function variants occur in a meaningful share of the population. In a long-running study of nearly 13,000 Americans followed for 15 years, Black participants carrying a PCSK9 loss-of-function variant (about 2–3% of that group) had roughly 28% lower LDL cholesterol and an 88% lower risk of coronary heart disease over the follow-up period; white participants with a milder, more common variant had about 15% lower LDL and 47% less coronary heart disease. None of these people had taken any medication or changed their diet or exercise habits — they were simply born with less cholesterol circulating in their blood, and had dramatically less heart disease as a result.
Combined with results from over 200 studies involving more than 2 million people, the pattern holds regardless of how LDL cholesterol is lowered — statins, ezetimibe, antibody therapy, or naturally occurring genetic variation — heart attack risk falls in proportion to how far LDL falls.
Why “Normal” Cholesterol Isn’t Always Low Enough
A 2009 study of over 136,000 Americans hospitalized for heart disease found that half had LDL cholesterol under 100, and three-quarters were under 130 — both considered “normal” on a standard lab report. The Spanish PESA study, which imaged the arteries of over 1,700 healthy middle-aged adults with no conventional risk factors, found that plaque buildup tracked closely with LDL level, and only became undetectable when LDL dropped to roughly 50–60. A 2026 trial (testing an LDL target of 55 versus 70, using ezetimibe added to a statin in over 3,000 people) found about a third fewer cardiovascular events over 3 years in the lower-target group — a difference of about 3 fewer events per 100 patients.
Does Lower Cholesterol Harm the Brain?
Because the brain uses cholesterol, some have worried that aggressively lowering blood cholesterol could impair cognition. This has been tested directly: in a trial of 1,200 people on a PCSK9-inhibiting antibody versus placebo, formal memory testing over 18 months showed no cognitive difference even when LDL dropped below 30. A large observational study of over 130,000 Danish patients with new diabetes found that starting a statin was associated with about 15% less dementia, not more — the opposite of what the cognitive-harm concern would predict.
ApoB: A More Precise Measurement
Beyond LDL cholesterol specifically, apoB — a protein present on every particle capable of depositing cholesterol into artery walls — is a more direct measure of the particles that actually cause damage. At birth, apoB levels run around 20–40; levels above that reflect a lifetime of accumulating risk. Newer cholesterol-lowering approaches focus on driving apoB down as far as safely possible: cheap generic medications like statins combined with ezetimibe remain effective first steps (a small share of people — roughly 1–2%, similar to placebo rates in careful studies — experience muscle aches attributable to statins specifically). Injectable PCSK9-inhibiting antibodies, FDA-approved since 2015, have been shown in the VESALIUS-CV trial to reduce heart attacks, strokes, and cardiovascular deaths by about 25% compared to placebo, with earlier treatment producing substantially more lifetime benefit than starting mid-life.
In July 2026, the FDA approved enlicitide (brand name Lipfendra), the first once-daily oral PCSK9 inhibitor, taken as a tablet on an empty stomach. In clinical trials it lowered LDL cholesterol by roughly 56–59% compared to placebo, with a side-effect profile similar to placebo — including no signal of the muscle aches sometimes seen with statins. It remains under patent and is priced accordingly, but represents a major step toward making powerful cholesterol-lowering more accessible without injections. Separately, an early-phase gene-editing therapy (a single infusion designed to permanently reduce PCSK9 activity) has shown LDL reductions of up to 62% sustained for at least a year and a half in a small phase 1 trial — an early but striking signal for a potential one-time treatment.
What This Means in Practice
Taken together: not smoking, a systolic blood pressure under 120 (higher if frail), a diet rich in fiber, potassium, and unsaturated fat, regular exercise, and effective treatment of obesity and elevated apoB address the overwhelming majority of modifiable heart attack risk. For people who have already addressed these risk factors and are considering cholesterol-lowering medication, a coronary artery calcium score can sometimes help clarify the decision — though it adds little additional value once risk factors are already being actively treated.
Frequently Asked Questions
Does lowering cholesterol too much harm brain function or increase dementia risk?
The evidence points the other way. A trial directly testing this found no cognitive difference after 18 months even with LDL below 30, and a large study of over 130,000 people with diabetes found statin use was linked to about 15% less dementia, not more.
If my cholesterol is “normal,” do I still need to worry about heart disease?
Possibly. Research has found that plaque can still build up in artery walls at LDL levels considered normal on a standard lab report — one study found it only stopped appearing around an LDL of 50–60. This is part of why some guidelines now suggest lower targets for people at risk.
Are GLP-1 weight-loss drugs actually proven to prevent heart attacks, or just weight loss?
Both. The SELECT trial specifically tested semaglutide in people with existing heart disease (not diabetes) and found a meaningful reduction in major cardiovascular events over about 3 years, not just weight loss.
Is there really a pill form of PCSK9 inhibitors now, instead of injections?
Yes — enlicitide (brand name Lipfendra) is a once-daily oral tablet approved by the FDA in July 2026, lowering LDL by roughly 56-59% in trials. It’s a different medication from inclisiran, an existing injectable PCSK9-lowering treatment given twice a year.
Heart Attack Risk Factors Worth Discussing With Your Doctor
- ☐ Smoking status, and support to quit if needed
- ☐ Home blood pressure readings, measured properly while relaxed
- ☐ A diet pattern rich in fiber, potassium, and unsaturated fats (DASH or Mediterranean-style)
- ☐ Weight and metabolic health, including whether a GLP-1 medication might be appropriate
- ☐ An apoB or LDL cholesterol test, and whether your target is appropriate for your risk level
- ☐ Whether a coronary artery calcium score would help clarify a treatment decision
This article is for general educational purposes and is not a substitute for personalized medical advice. Speak with a qualified healthcare provider before starting, stopping, or changing any medication, including blood pressure or cholesterol-lowering treatment.