Diets like the Paleo diet have become very popular. The Paleo diet is based around eating similar foods to what scientists believe our ancient hunter-gatherer ancestors ate. The theory is that our bodies and our genetics have been built to eat and digest this type of food rather than the processed food we eat today. Although the Paleo diet is up for debate as to whether its requirements actually are what our ancestors ate and if it is indeed good for us, the discussion of genetics versus nutrition has become an important one.
Enter nutrigenomics. Nutrigenomics is a new subfield in the world of nutrition which studies how health and nutrition are to be understood in context to someone’s personal genome and environmental factors. The hope is that with more understanding of this relationship, we can prevent or cure chronic diseases by prescribing an individualized diet based on genetics and environmental factors.
We know that certain people have food-related conditions that are influenced by their genes. For example, lactose intolerance is due to a genetic variation that produces defective lactase enzymes which results in being unable to digest lactose properly. Genetics are also associated with increased sensitivity to caffeine, alcohol, or gluten. But with further study, nutrigenomics is showing that the relationship between food and genes can also go the other way. It seems that some of the foods we eat may actually cause genetic differences. The nutrients in food can actually alter the physical expression of the genes.
Within the past 25 years, there have been several studies researching how food and nutrients can control gene expression–are they inhibiting it or encouraging it? This can potentially be very helpful for those suffering from chronic diseases. In some studies when subjects would eat more of one type of food, certain gene transcriptions would be inhibited, or if they avoided eating other foods there would be a reduction in the response of certain genes. Even calorie restriction or a change of diet and adding exercise can cause a reduced or increased gene response.
At the moment most of the testing in nutrigenomics is commercial. Companies like DNAfit will send an individual a DNA swab kit and then check the DNA genome for certain known genes that might affect how a customer absorbs nutrients, reacts to toxins, and even how they respond to different types of exercise. Based on the genetic profile, they will send the customer an individualized diet and exercise program.
Are these diets worth buying into? Not necessarily. Scientists at Stanford University tested the effects of a low-fat diet versus a low-carb diet that was related to the subjects’ genetic pattern to see if one diet would be more effective than the other. In the end, there was no significant difference based on the genetic pattern. But nutrigenomics is a fairly young science, and, although at the moment the amount known is limited, perhaps as there is more research, this will change.
Imagine a future where doctors could prescribe a specific diet based on your genetics to solve chronic diseases, prevent cancer, or just improve your wellbeing! For now, scientists are still trying to figure out the connections, but perhaps this future is not too far off.
References
- Nutrigenomics: What Do Diet and Genes Have To Do With Health?
- Nutrigenomics 101
- In the Know about Nutrigenomics
- Genetics and nutrition
- Genomic interactions with disease and nutrition
- DNAFit
- Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial