All about your immune system

Your active or adaptive immunity is what develops over time in reaction to invading infections or unhealthy cells that have mutated. It’s also evoked when you get a vaccination. White blood cells are the army that defends you — they include lymphocytes (Band T-cells) and others that target bacteria or take out the trash. This complex system turns out to act and react in ways that researchers are just discovering.

1. High-fat diets hide cancer cells from the immune system. Researchers from MIT, Harvard and Cold Springs Research Laboratory have found that a fatty diet interrupts the conversation between cells in your intestines that help identify rogue cells and immune cells that patrol the gut looking for cancer cells to disable. When they can’t talk to each other, you have an increase in your risk for colon cancer.

Overall, when working correctly, immune cells kill off cancer cells. However, when the immune system can’t keep up with the challenges thrown at it, instead of guarding against cancer, it may help cancer cells thrive.

2. You have memory B- and T-cells. Day to day, B-cells produce antibodies, killer T-cells attack infected tissue and helper T-cells support B-cell production of antibodies. Those antibody levels can sink over time. But there are also versions of T- and B-cells that remember their first encounter with an infection. So, you can battle off repeat exposures to specific culprits — sometimes for decades. Research shows that people who contracted COVID-19 and then were vaccinated have vast stores of these memory immune cells — providing extra immunity.

3. When you’re sick, some symptoms are NOT from your illness, but from your immune response. If you get a stuffy nose from a cold-producing rhinovirus, it is not the virus that triggered it, but the inflammatory response of your immune system. Infection in your nasal passages causes histamines to be released that then dilate blood vessels and increase the migration of white blood cells to infected tissue lining your nose. When you get the flu, that fever-achy feeling is also from your immune system’s response.