> One idea is that intestinal worms - which dampen immune reactions - could be more common and this may help protect the heart. That worm infects most of the p

> One idea is that intestinal worms - which dampen immune reactions - could be more common and this may help protect the heart. That worm infects most of the population: > And about 70% of the population has a parasitic worm infection [Ascaris lumbricoides, a type of roundworm]. ... Up to a third of the world's population also lives with such infections. https://www.bbc.com/news/health-34857022 https://www.bbc.com/news/health-34857022 Before latching onto exercise or diet as the primary factors, it's worth considering the effect of this worm infection. It could influence the heart indirectly through nutrient flow, immune suppression as suggested for the original article or the one on pregnancy, or directly via for example larvae/segments, etc. BTW, the lifecycle of this thing is the stuff of nightmares: > Ascaris lumbricoides, a roundworm, infects humans via the fecal-oral route. Eggs released by adult females are shed in feces. Unfertilized eggs are often observed in fecal samples but never become infective. Fertilized eggs embryonate and become infective after 18 days to several weeks in soil, depending on the environmental conditions (optimum: moist, warm, shaded soil).[5]. When an embryonated egg is ingested, a Rhabditiform larva hatches then penetrates the wall of the duodenum and enters the blood stream. From there, it is carried to the liver and heart, and enters pulmonary circulation to break free in the alveoli, where it grows and molts. In three weeks, the larva passes from the respiratory system to be coughed up, swallowed, and thus returned to the small intestine, where it matures to an adult male or female worm. Fertilization can now occur and the female produces as many as 200,000 eggs per day for 12–18 months. These fertilized eggs become infectious after two weeks in soil; they can persist in soil for 10 years or more.[6] https://en.wikipedia.org/wiki/Ascaris_lumbricoides https://en.wikipedia.org/wiki/Ascaris_lumbricoides Clearly, the juvenile state spends some time in the circulatory system, where it should have some opportunities to influence coronary artery calcium. I looked for studies that examined the incidence of heart disease/CAC buildup among other infected populations but didn't immediately find anything.