Have you ever wondered why coffee affects one person differently than another? Or why onions cause bloating for some people but not for others?
Our genes may help explain some of these differences. Nutrigenomics is the study of how genes and food interact. It can offer clues about how your body processes certain foods and nutrients.
That information can help you make more informed choices. It is not a complete picture of your health, but it can be one helpful piece of it.
Genes can affect how you process caffeine
The CYP1A2 gene helps the body break down caffeine. Some people process caffeine faster than others.
This may help explain why one person can enjoy coffee late in the day and sleep well, while another feels jittery or has trouble falling asleep. Research has also explored whether caffeine metabolism is linked to heart health. But a gene result alone cannot tell you what will happen to your health.
Your response to caffeine can depend on more than genes. The amount you drink, your sleep, your health, and some medicines can also matter. Paying attention to how you feel can help you decide what works best for you.
Food sensitivities can differ from person to person
Some people feel bloated or uncomfortable after eating certain foods, such as onions. Onions contain FODMAPs—a group of carbohydrates that can be hard for some people to digest.
These symptoms do not always mean a person has a specific gene that explains them. Digestion is affected by many things, and food sensitivities are different for everyone.
A Registered Dietitian (RD) can help identify possible food triggers and guide you through changes to your diet. This is especially helpful with a low-FODMAP diet, which is meant to be done with care. The goal is to find foods that feel comfortable while keeping meals varied and nourishing.
Genetic tests are one piece of the picture
At-home genetic tests can provide information about certain traits. But they cannot tell you everything about your health or predict exactly how you will respond to food.
Your health is shaped by many factors, including:
Your genes
Your usual eating habits
Your digestion and gut health
Your activity and sleep
Your medical history and medications
Your environment and daily routines
Some questions also need clinical tests. For example, a blood test can measure your vitamin D level. A genetic result may offer a clue, but it cannot replace that measurement.
Make the information useful
A Registered Dietitian can help you understand what test results may mean for you. They can consider your genes alongside your symptoms, health history, and any relevant lab results.
Together, you can build a practical plan—one that fits your needs, preferences, and everyday life. The aim is not to put people into boxes or create strict food rules. It is to use good information to support choices that work for each person.
A more personal approach to nutrition
People are different, and nutrition advice does not always work the same way for everyone. Nutrigenomics may help us understand some of those differences.
More information can be empowering. When it is interpreted with care and used alongside other health information, it can help people and their health professionals make more informed choices. Personalized medicine is moving toward a future where care can better reflect the individual—and nutrition is part of that future.
