Understanding immunity
changes how you understand your health.

One faulty gene warps red blood cells into stiff crescents, causing excruciating pain crises. Casgevy (exa-cel), approved by the FDA on 8 December 2023, edits the patient’s own blood stem cells to switch a healthy backup gene back on, so the body makes blood that doesn’t sickle. In the phase 3 trial, 29 of 30 evaluable patients went a year or more with no severe pain crises. It is a one-time, complex and very expensive treatment given at specialist centers; if sickle cell disease affects your family, ask a hematologist whether it could be an option.

In 6,278 adults followed for 25 years, those who flossed at least weekly had a 22% lower risk of clot-type (ischemic) stroke, 44% lower risk of the stroke caused by a clot from the heart, and 12% lower risk of atrial fibrillation — even after accounting for brushing and dental visits. A likely reason is that gum disease fuels low-grade, body-wide inflammation that can damage blood vessels and the heart’s rhythm. This is preliminary conference data that has not yet been peer-reviewed, and it shows an association, not proof. The practical point: flossing once a day takes about 30 seconds and is one of the cheapest things you can do for your heart and brain.

Gel-manicure dryers bathe your hands in UVA light, which is linked to skin aging and skin cancer. In lab-grown cells, one 20-minute session killed 20–30% of the exposed cells and three sessions killed 65–70%; the survivors showed DNA damage and mutation patterns seen in human skin cancer. This was a lab study on cells, not people, so it doesn’t prove gel nails cause cancer — but it’s a credible warning. The practical point: you don’t have to give up gel nails, but cut the UV dose — apply SPF 30+ sunscreen to your hands first, or wear fingerless UV gloves.