It is my opinion that both of the adults residing in the White House leave much to be desired when it comes to intellectual ability and cognition. I believe that I have posited plausible arguments at AT, e.g., here, here and here.
Now there is a scientific explanation providing validation.
First, a quote from FLOTUS:
"I am a believer there is a beet gene. People who love beets love them and people who hate beets can't stand them. Neither the President nor I have the beet gene..."
Daily Dose Of Beet Juice Promotes Brain Health In Older Adults
Researchers for the first time have shown that drinking beet juice can increase blood flow to the brain in older adults - a finding that could hold great potential for combating the progression of dementia.
The research findings are available online in Nitric Oxide: Biology and Chemistry, the peer-reviewed journal of the Nitric Oxide Society and will be available in print soon. (Read the abstract.)
"There have been several very high-profile studies showing that drinking beet juice can lower blood pressure, but we wanted to show that drinking beet juice also increases perfusion, or blood flow, to the brain," said Daniel Kim-Shapiro, director of Wake Forest University's Translational Science Center; Fostering Independence in Aging. "There are areas in the brain that become poorly perfused as you age, and that's believed to be associated with dementia and poor cognition."