Certain genes have been associated with an increased risk of strokes and heart attacks. Researchers have studied whether people with some of these genes can lower their risk of cardiovascular disease (CVD) with dietary changes. They can.

A study from McGill University, published in 2011 in PLoS (Public Library of Science) — Medicine, examined heart attack rates in 8000 people who carried a gene called 9p21. Four thousand of the research participants ate large amounts of fresh produce, while the other half ate the standard Western diet.

Researchers found that those individuals who ate a diet high in raw fruits and vegetables decreased their risk of cardiovascular disease by 50 percent. They reported hopefully that “…the deleterious effect of 9p21…might be mitigated by consuming a diet rich in fresh fruits and vegetables.”

A diet rich in fresh produce probably has not one, but two benefits: Firstly, you obviously eat more fruits and vegetables, but secondly, and equally important, is that replacing manufactured items with produce also likely reduces the volume of ultraprocessed items consumed.

I would have written a slightly different conclusion: I would say that whereas the Western diet is deleterious, its effect happens to be greater in certain individuals with particular genetic makeups. A diet rich in fresh fruits, vegetables, and legumes likely reduces the risk of heart attack across the population, but the benefit may be more dramatic in individuals who carry certain particular genes.

Let us consider the well known metaphor of frogs in hot water. High temperatures will be deadly, but not all frogs will succumb immediately. Those that are most sensitive will be the first to go. Let’s run that experiment here:

Begin with a large pot of cool water, and frogs from all over the world. Then move the pot to a fire. As the water temperature begins to rise, a few frogs will begin to struggle immediately. As the temperature rises further, more and more will die until, finally, none remain alive. What can we learn from this?

• You could run the experiment a few times and learn to predict the effects at each temperature. 

• You could do a chromosomal analysis of frog DNA to look for commonalities among the frogs with greater sensitivity to rising temperatures. 

• You could conclude that frogs with the identified chromosomes could be protected by avoiding high heat. Or, 

• You might recognize that high temperatures constitute an abnormal, unusual, and externally administered environmental stress, and that while some frogs appear more tolerant than others, high temperatures are ultimately lethal to them all.

If I were to generate a diagnosis for this phenomenon, I might call it dyscalorimetry. But dyscalorimetry doesn’t mean that heat intolerance is genetic. It means that hot water is deadly. 

In the same way, we can continue to improve our ability to identify those individuals at highest risk of intolerance to the Western diet, put them on cholesterol-lowering medication, order nutrition consults, and schedule more stress tests. Or we could markedly increase government stipends for produce.