It turns out what's referred to as "good" cholesterol might actually lead to a much greater risk of heart disease.
Good cholesterol, or high-density lipoprotein, was previously believed to counteract the effects of so-called "bad cholesterol" and decrease the risk of heart disease.
Eating certain foods like avocados and exercising is believed to raise HDL levels in the bloodstream. A Cambridge University study looked at 1,700 people with a genetic mutation that causes high levels of good cholesterol to get a better understanding of the protein.
It found that the group had an 80 percent increased risk of heart disease, which is about the same risk brought on by smoking.
All this isn't to say there couldn't be some health benefits to HDL. But researchers suggest past efforts have been trying to get those benefits the wrong way.
The Cambridge study instead says it might not be the overall levels of cholesterol that's important but the size of the particles and how good they are at transporting excess cholesterol to the liver.
The researchers suggest further study is needed into how good cholesterol interacts with the body, instead of focusing on the amount in the bloodstream.
This video includes images from Getty Images.