I've made it no secret over the years of writing this blog that I have a problem keeping my weight down. If I'm careful about the amount I eat and exercise regularly, I can control it. When I stop those good habits, within days the weight starts to come back on. One of my sons can eat anything and everything he wants, and it never effects his weight. How is this possible? I've always believed it's because he has something in his genes that comes from his father's side, not mine, that gives him a super metabolism.

That, of course, has been my completely unscientific take on the disparity between how food affects different people, but I may not be so off-base. According to the science behind nutritional genomics, or nutrigenomics as it's become known, our genes have a lot to do with how our bodies react to what we put into them.

Nutrigenomics is the "study of how foods affect our genes and how individual genetic differences can affect the way we respond to nutrients (and other naturally occurring compounds) in the foods we eat," according to NCMHD Center of Excellence for Nutritional Genomics at University of California, Davis. This new branch of genetic research is getting a lot of attention because of the practical applications of its findings: it may be able to be improve not only the health of the general population, but also the health of individuals based on their personal genetic makeup.

Researchers are working off of these five tenets, according to UC Davis:

  • Diet can be a serious risk factor for a number of diseases.
  • Common dietary chemicals can alter our gene expression or structure.
  • The degree to which diet influences the balance between healthy or not may depend on our genetic makeup.
  • Some diet-regulated genes likely play a role in the onset, progression and/or severity of chronic diseases.
  • Dietary intervention based on personalized nutrition can be used to prevent, mitigate or cure chronic disease.

None of these tenets seem crazy. We've always been told "you are what you eat." Now that maxim is getting backed up with science, and the possibilities for improved health via "personalized nutrition" are exciting.

Putting nutrigenomics into practice

Healthy salad Your DNA can tell scientists whether a diet high in protein or a diet low in carbs is best for your body. (Photo: alisafarov/Shutterstock

Scientists are looking at areas where changing genes can help with health issues, like lactose intolerance. Researchers have identified the genetic variant responsible for whether or not we can consume fresh dairy without complications. It's believed this discovery "should now make it possible to design individualized dietary interventions based on a genetic test for lactose intolerance in early childhood."

Treatments for cancers, diabetes, heart disease and more are being studied through the lens of nutrigenomics, and yes, a solution for weight loss is a goal, too. In fact, a soon-to-launch company called Habit will analyze your DNA and design a diet for you, according to Popular Science.

After eating meals that Habit provides, you'll prick your finger and send blood samples to be analyzed. That analysis may find your body processes carbohydrates best so the resulting diet would be based around that. Or, it may find you need a diet high in protein and low in carbs and fats. Your metabolism rate is analyzed, too, so calorie needs can be adjusted based on metabolism.

I find nutrigenomics fascinating and the promise of the practical uses of this science very encouraging. I do have to wonder, though, even if we have accurate information about what specific foods are optimal for our individual health, will we change our diets? Going back to my own limited knowledge about how to keep my body at a healthy weight, I know what works, but I frequently don't do what works. Sometimes my human nature wins out over scientific knowledge. Maybe that's in my genes, too.

Robin Shreeves ( @rshreeves ) focuses on food from a family perspective from her home base in New Jersey.

What is nutrigenomics?
Your genes may have the secret to a custom-made diet for your body.