#20 - A recent study confirmed that salt intake tends to

[jona_zx]

I am confused about the last part of E " ensures that their blood pressure does not drop too low". So if they were getting a high salt diet in the study, why would they be showing very low blood pressure if they should be ensured not to have very low pressure?

[Amber Thomas]

Hi jona_zx!

The key difference here is between "very low" and "too low." Let's take a look at some real-world numbers to help clarify this distinction.

Answer Choice E tells us that: "persons suffering from abnormally low blood pressure have heightened salt cravings, which ensure that their blood pressure does not drop too low."

The average blood pressure is 120/80. The threshold for blood pressure being "too low" is around 90/60. Relatively/very low (but not "too low") blood pressure could then be anywhere between 120/80 and 90/60. So, individuals with very low blood pressure will consume more salt as a result of their cravings, raising their blood pressure levels such that they are not "too low," or dangerously low. However, they could still fall in the range of relatively/very low blood pressure.

I hope this helps!