There is a lot of emphasis on personalized nutrition, but perhaps we should focus on taking personal responsibility for our health.
“Personalized nutrition (PI) is rooted to the idea that one size does not fit all’ and who doesn’t want to think they are special? The idea of personalized nutrition is inherently appealing to our egos. that’s why simple messages that recognize individuality resonate deeply with us, and why such messages are popular in marketing and sales. This focus on uniqueness has being pushed the creation of personalized food, along with the suggestion that “3D food printing appears to be a good candidate for food customization.”
Now, there are certainly some legitimate differences between people. Some have an allergy to peanuts and keel if they eat a peanut, others have celiac disease and gluten must be avoided, and some are genetically lactose intolerant. There is an enzyme mutation common in some areas of Asia protects against alcoholism, because people with the altered enzyme do not metabolize alcohol as efficiently, so toxic metabolites accumulate. I posted a fascinating video about fast and slow metabolizers of caffeine and the difference in health benefits that actually extends in sports performance. Caffeine is ergogenic—it improves performance—but only in fast metabolizers, shaving more than a minute off 10 kilometers (about 6 miles) of cycling, while slower metabolizers either had no benefit or the caffeine actually slowed them down, adding two minutes to their cycling time, depending on what kind of genes this enzyme breaks down. You can see these results below and at 1:24 in my video How useful is personalized nutrition?.
But for most people, in most cases, we do hectare more similar than different.
While there is a specific minority of people who need a more personalized approach to nutrition, there is currently insufficient evidence to support truly personalized nutrition for most people. However, a surprising number of direct-to-consumer genetic testing companies have multipliedoffering personalized nutritional advice. For example, there are supplement companies that claim to help consumers optimize micronutrient status based on a handful of genetic variants, even though most variants explain only a few percent of the difference in levels between people.
Personalized nutrition it is part of a broader push toward personalized medicine, also known as precision medicine. There it is a “mass cultural fascination” with personal control over diagnosis, disease treatment and prevention, driving demand and intense commercialization. But unlike monogenetic diseases—which are rare genetic diseases caused by a single malfunctioning gene, such as hemophilia or sickle cell disease—most diseases are caused from a complex interplay between multiple genes and environmental factors, which constitute “a major challenge for the realization of personalized medicine”.
Take for example something like adult height. Researchers have I establish at least 40 locations on our chromosomes that have been associated with human height, which is strongly heritable. Genes from parents account for about 80% of the difference in height between people, yet these dozen or so identified genes explain only about 5% of the variation in height between individuals.
Researchers find these genetic links using genome-wide association studies, in which all chromosomes are scanned to look for statistical associations between diseases and any specific stretches of DNA. This is interesting, but companies that market genetic susceptibility tests are reinterpreting these data as predicting individual risks. But all you really get are modest genetic associations with a slight increase in disease risk and little predictive power compared to more important contributions of things we already know, like lifestyle behaviors. Currently, his practice using a person’s DNA to predict disease “has been judged to provide little or no useful information.”
For example, let’s say the genetic analysis of a person he says are at slightly higher risk for a serious condition compared to others in their ancestral group. This person was advised to exercise, keep a low weight, not drink too much alcohol, and eat fruits, vegetables, and whole grains. It’s sound advice, but we should live this way regardless of our genetic risk. And we know—at least we should know—these simple, basic strategies for reducing the risk of common chronic diseases. “The problem, of course, is that very few people live this way. In fact, to be more precise, almost no one lives this way.” That’s not just exaggeration — nationwide surveys demonstration that nearly everyone in the United States consumes a diet that does not meet even the modest recommendations of the Dietary Guidelines.
Indeed, almost ‘no one in the United States is eating healthy diet.” Such findings remind us that when it comes to public health, “concern about personalizing our preventive strategies based on genetic risk information borders on the absurd.”
Doctor’s note
Here’s the video I mentioned about fast and slow metabolizers of caffeine and the difference in health benefits that extend to athletic performance: Friday Favorites: Do Coffee’s Health Benefits Apply to Everyone?.
For more on lifestyle approaches, see the related posts below.
