Genes and Dietary Destiny

Genes are not destiny. We tire of people who cling to this one side of the false nature versus nurture dichotomy. They’re stuck on the fallacy of thinking that genetic and environmental influences on health must sum to 100 percent. One or the other must be dominant, they seemingly assume. But the truth is that both can play a big role in health and related behaviors. So can genes play a role in our dietary destiny?

At the ASN Nutrition Live 2022 conference, research from Julie Gervis and colleagues shows us that genes can have a strong influence on the dietary patterns we choose to follow. Thus, it’s indeed possible that genes shape our dietary destiny. Are they, by themselves, determinative? Of course not.

Taste-Related Genes

Gervis examined the relationship between genetic risk scores for taste preferences, diet quality, and markers of cardiometabolic health. These were waist circumference, blood glucose, blood pressure, and cholesterol. What they found was a clear association of genetic scores for sweet, bitter, and savory taste perception and the quality of individual diets. Likewise, those genetic taste perception scores also predicted some of the risk factors.

For example, stronger genetic traits relate to sweet taste predicted a diet with more fish and seafood. It also predicted higher levels of HDL (good) cholesterol. In a similar way, people with strong genetic traits for sensing bitter tastes tend to eat less of cruciferous vegetable. That is, they’re less likely to eat their broccoli.  Said Gervis:

“We know that taste is one of the fundamental drivers of what we choose to eat and, by extension, our diet quality. Considering taste perception could help make personalized nutrition guidance more effective by identifying drivers of poor food choices and helping people learn how to minimize their influence.”

Destiny?

So let’s get this straight. Genes are neither the sole determinants of our destiny, nor are they trivial factors. There are folks who insist (we’re looking at you Harvard SPH) that genes are not important to, for example, obesity risk. This is a false argument. But it springs from a desire to promote the importance of a toxic environment. Nothing wrong with that. The only problem comes when these advocates twist facts to fit the story they’re selling.

The truth here is that both can be important. As Gervis et al show in their research, genetic scores for taste perception may shape the dietary patterns that we adopt over a lifetime. Yet, we have choices to make. Dietary patterns are extremely complex. We might not come to love broccoli if it tastes bitter to us, but the options for other foods that bring us health and pleasure are abundant.

Likewise, obesity is a highly heritable condition. Our environment plays an important role in triggering it. But if we can face facts, we have options for dealing with it. We do indeed have the capacity to shift the equation in our favor. Sometimes a little. Sometimes a lot.

Click here for the Gervis study abstract, here, here, and here for further perspective on it. For more on the fallacy of zero-sum thinking about genetic and environmental influences on health risks, click here.

Red Wall Destiny, painting by Wassily Kandinsky / WikiArt

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.

June 16, 2022