If your doctor advises to lower your sugar intake because you're at risk for diabetes, you're less likely to take this advice than if he or she tells you that you need to cut down on the sugar because your family has a history of diabetes.
According to a recent study published in PLoS One, when it comes to nutrition, we place a lot of weight on our genes.
Researchers from the University of Toronto report that personalized dietary advice based on a person's genetic makeup improves eating habits compared to standard, unpersonalized dietary recommendations.
"We conducted the first randomized controlled trial to determine the impact of disclosing DNA-based dietary advice on eating habits," said lead author Ahmed El-Sohemy in a press release. "We found that people who receive DNA-based advice improve their diet to a greater extent than those who receive the standard dietary advice. They're also the ones who need to change it the most."
El-Sohemy is the Canada Research Chair in Nutrigenomics, which is an area of study that aims to understand why the same foods affect people differently. Personalized nutrition, the focus of this study, is an application of nutrigenomics that helps doctors customize a patient's recommended diet according to his or her genetic makeup.
The researchers collected data on the intake of caffeine, sodium, vitamin C, and sugar from 138 healthy young adults who were then placed at random into two different study groups. One was given DNA-based dietary advice for each of the four dietary components of interest, and the other group was given the current standard dietary advice for the same components, but without genetic information.
Using food frequency surveys, the team assessed changes in the participants' dietary habits after three and 12 month periods. They found that those who received DNA-based dietary advice started to show improvements in their diets after three months and the changes became even more apparent after 12 months.
More specifically, the researchers found that people who had a gene tied to salt intake were able to reduce their sodium consumption more effectively.
Though no effects were noted on the other three dietary components of interest, likely because most of the subjects were already getting enough of them in their diet, the researchers still believe the findings are groundbreaking.
"This study addresses some notable limitations in previous studies that attempted to measure the impact of disclosing genetic information on lifestyle changes," said El-Sohemy. "Previous studies focused on disease risk prediction rather than metabolic genes that affect specific components of the diet. This is the first time that the impact of dietary advice based on diet-related genes with specific actionable advice has been tested."
So if you're having trouble adhering to a diet recommended by your doctor, it might be worth it to ask about genetic testing. You can't rewrite your genetic code, but understanding your family's history could give you better control of your health.