DNA testing has become very popular, marketed to help you determine a variety of aspects of your health and genetics. This has led to a spinoff of DNA-based nutrition testing, suggesting that your genetics can tell you what to eat and what to avoid.
Many are targeted to athletes, to potentially improve performance. DNA diets are still new to the nutrition science scene, and understanding their potential pros and cons is helpful if you’re considering following one.
Testing your DNA can identify certain genetics that may put you at a greater risk for hereditary diseases. As for nutrition, the idea is that DNA testing will identify how your body responds to foods, guiding you to make changes that lower inflammation and disease risk.
Some companies even say “eating for your genes” can help promote successful weight loss or improve performance. While this is attractive consumer marketing, being able to use a DNA test in this way is much more complicated than how it’s often presented, and these claims lack scientific evidence.
There are a number of companies offering DNA testing in conjunction with nutrition counseling and weight loss guidance. From looking through their websites, it appears that much of their advice is designed to be very generic while feeling unique to you, likely to make the basic testing results you’ll receive feel much more weight-bearing. Additionally, some companies say their DNA testing sheds light on the personalized dietary supplements you need to take, and then sells you those supplements.
A 12-month long 2018 randomized controlled trial published in JAMA examined the weight loss effects of a healthy diet either low in fat or low in carbs, among 609 adults 18-50 years old with a BMI between 28-40 and no existing diabetes. The researchers were interested in determining whether genotypes or insulin secretion are related to the dietary effects on weight loss.
They found that there was no significant difference in weight changes between the two diet patterns, and that neither genotypes nor insulin secretion was associated. In other words, genotype was not helpful in determining which diet pattern was beneficial for the participants.
So while many DNA testing companies will say they can use your genes to predict your response to food, or identify the best way of eating for weight loss, this isn’t completely accurate. What they can tell you – like your risk for iron deficiency anemia, or how sensitive you are to caffeine or alcohol – is interesting, but isn’t actually that unique.
While personalized nutrition is important, much of this can be managed without an expensive DNA test.
Don’t get me wrong, a DNA diet is fascinating, but further research is needed. In fact, a 2019 study concluded that there’s not enough information specifically on genes and exercise performance quite yet. Improving overall diet quality can certainly improve body composition and athletic performance, but more studies are needed.
When it comes down to it, we’ve long known that eating a diet of poor nutritional quality won’t fuel anyone well. Oppositely, eating primarily high quality foods is your best bet for optimizing health, lowering risk for chronic disease, and fueling athletic performance.
While an interesting area of science, DNA diets are still a novel idea and have a long way to go. Genetics are complicated. These results simply can’t be applied in the same way to every person in a way that would make me recommend DNA diets right now.
Rather than putting so much weight on a diet based on your DNA, a good approach is to give different foods a try and see how you respond to them, monitoring your weight and blood biomarkers at wellness visits, and making adjustments as fit. And of course, meeting with a sports dietitian can help. Contact us to schedule a meeting for individualized sports nutrition coaching.