In older adults with heart disease risk factors, how much they exercise, smoke, or their education level matters more for artery health than how much saturated fat they eat.

Eating a lot of fatty foods like butter and red meat doesn't seem to make the arteries thicken more in older adults at risk for heart disease, once you account for how much they exercise, smoke, or their education level.

No common gene differences found in this group of older adults make them more or less sensitive to the effects of eating saturated fat on their artery thickness.

If healthy adults have higher 'bad' cholesterol levels, they’re more likely to show early signs of artery hardening, like thicker artery walls or plaque buildup in the neck arteries.

Even though belly fat is often blamed for heart problems, in young, active adults, it doesn’t seem to directly affect artery thickness — fitness and triglycerides matter more.

Whether you're a man or woman, young or old, eating more saturated fat doesn't seem to affect your heart disease risk any differently — the link is about the same across all groups.