[brador]

And this is the real reason.

The oatmeal put them on a crash diet of 1000 calories a day. And filled them so they didn’t reach for non reported snacks.

[FrancisMoodie]

They had a control group who also went on a reduced calorie deficit but without oats and found that the oats eating group had a much higher decrease of cholesterol, it's in the article.

[raydev]

Oats group saw a decrease of 10% but the number for the control group is not given.

[_flux]

Two-day crash diet can reduce LDL levels for 6 weeks?