The DNA sequence you were born with is remarkably stable. But having a gene and using that gene are two different things.

At any given moment, cells are activating some genes, quieting others and adjusting how strongly particular genes are expressed. Diet is one of many environmental influences that can affect this activity.

Some of those effects involve epigenetics, chemical modifications to DNA or the proteins around it that help regulate how genes are used without changing the underlying DNA sequence.

Think of the genome as an enormous recipe book. Nearly every cell contains essentially the same collection of recipes, yet a liver cell and a brain cell make very different things. Part of the reason is that molecular instructions help determine which recipes are accessible and how often they are used.

Food can contribute ingredients involved in those instructions.

Nutrients found in everyday foods, including folate in leafy greens, vitamin B12 in fish, meat and dairy, and choline in eggs and soybeans, provide compounds the body uses in processes that can influence gene regulation.

Compounds found in broccoli, cabbage and other cruciferous vegetables can also influence enzymes involved in regulating gene expression. Researchers are studying how these effects may relate to inflammation, cellular defenses and cancer biology.

Perhaps the most dramatic example comes from honeybees. Worker bees and queen bees are genetically very similar, but larvae destined to become queens receive a diet rich in royal jelly. That nutritional difference helps trigger profound changes in gene expression and development, producing a queen that is larger, fertile and far longer-lived than a worker.

In humans, food’s influence on gene activity is subtler. A serving of broccoli won’t dramatically alter how your genes behave, but over time, diet can be one of many factors influencing which genes are more or less active.

But the underlying idea is striking: your genes aren't merely instructions you inherit. How your cells read and use those instructions is influenced, in part, by the world around you, including what you eat.