Dr. Kumar’s Take:
This fascinating study explores how traits that once helped our ancestors survive—like high cholesterol levels or better salt retention—may now be working against us. These genetic adaptations, once useful in fighting off infections or surviving heat and dehydration, are mismatched with today’s lifestyle of overnutrition and processed food. The result? Increased risk for heart disease, high blood pressure, and stroke.
Actionable tip: If heart disease runs in your family, it may not just be diet—your genes might be playing a role. But healthy lifestyle choices like reducing processed foods, staying active, and managing stress can help offset these inherited risks.
Key Takeaways:
✔ High cholesterol may have helped early humans fight infection—but now raises heart disease risk.
✔ Salt-retaining genes in African ancestry may have helped people survive dehydration—but now raise blood pressure.
✔ The shift from survival advantage to modern disease is a case of evolutionary mismatch.
Brief Summary:
This review article explores how natural selection may have shaped human genes in ways that increase modern-day risks for high cholesterol and high blood pressure. Traits like salt retention and high immune activity were likely beneficial during times of frequent infection and limited food. Today, however, those same traits may contribute to chronic conditions like heart disease and stroke when combined with a modern diet high in fat and sodium.
Study Design:
This was a narrative review by researchers from the Czech Academy of Sciences and the Institute of Clinical and Experimental Medicine in Prague. They analyzed historical, genetic, and epidemiological data to propose that many cardiovascular risk factors are the result of ancient adaptations that became harmful in today’s environment.
Results:
- Pro-inflammatory immune cells in fat tissue were linked to high cholesterol, especially non-HDL cholesterol.
- Infections were the main killers in the past, so having higher cholesterol and more immune cells likely helped survival.
- In African Americans, genes favoring sodium retention helped survive transatlantic slavery conditions—but today lead to high blood pressure.
- Mortality records from the 1800s suggest people with familial hypercholesterolemia lived longer during times of high infection.
- Today, those same traits increase risk for heart attacks and strokes.
The Evolutionary Story Behind Cholesterol and Blood Pressure
Our ancestors faced constant exposure to deadly infections, extreme climates, and limited nutrition. Traits like:
- Higher cholesterol (to build cell walls and fight infection),
- Stronger immune response (more inflammatory macrophages),
- Better sodium retention (to prevent dehydration),
…were valuable for survival. Over time, natural selection made these traits more common. But now, in an environment of excess calories, processed food, and sedentary lifestyles, they’ve become liabilities—contributing to the rise in chronic diseases like heart disease and hypertension.
This paper supports the broader theory of evolutionary mismatch, where genes adapted for one environment become harmful in another. For more on this topic, check out related posts:
Related Studies and Research
Inflammation and Cardiovascular Disease – Reviews how inflammation functions as a central driver of heart disease, potentially shaped by evolutionary pressures.
Inflammation, Cholesterol, and Heart Disease – Explores how lipid levels and inflammatory markers interact to influence cardiovascular outcomes.
LDL-C and Mortality in the Elderly – Investigates whether standard lipid targets apply to older adults, considering genetic and inflammatory variation.
Statins and Primary Prevention: The Debate – Evaluates the evidence for statin use in low-risk individuals, where inflammation may be a more relevant marker than LDL alone.
Frequently Asked Questions
Why would high cholesterol ever be helpful?
Infections used to be the biggest threat to survival. Higher cholesterol may have helped build stronger immune defenses, particularly in fat tissue.
Why is hypertension more common in African Americans?
Genetic traits that helped retain salt and fluids during hot climates or dehydration may now raise blood pressure when salt is plentiful in the modern diet.
Can we change our genes?
We can’t change our DNA, but we can change how our genes are expressed through lifestyle. Regular exercise, a healthy diet, and stress management can greatly reduce risk—even if the genes are there.
What is evolutionary mismatch?
It means a trait that was helpful in our ancestral past is now harmful because the environment has changed too quickly for evolution to keep up.
Conclusion
This study reminds us that modern health issues like high cholesterol and blood pressure are not just about poor choices—they’re also part of our evolutionary history. While we can’t change the past, we can shape our future by understanding our bodies better and making lifestyle choices that support heart health in today’s world.