In adults from Cameroon, the more salt they have in their urine, the more likely they are to have high blood pressure — every little bit of extra salt is tied to a slightly higher chance of high blood pressure, even after considering age, weight, and belly size.

In city-dwelling Bantu adults in Cameroon, higher blood pressure tends to go hand-in-hand with more salt coming out in their urine — and this link still holds true even when accounting for age, weight, and belly size.

City-dwelling adults in Cameroon are excreting way more salt in their urine than people living in the forest who hunt and gather food — more than double — which probably means they're eating a lot more salt in their diets.

In people with high blood pressure in Shanxi Province, those who excrete more sodium in their urine tend to have higher blood pressure—even when you account for things like age, weight, diabetes, and cholesterol—and this link is even stronger in women.

If you have heart disease and eat more salt, your blood pressure tends to go up — for every extra gram of salt you excrete in urine, your top blood pressure number goes up by about 1.3 points and your bottom number by about 0.5 points.

In older adults in rural South Africa, the less salt they eat, the lower their blood pressure tends to be — every gram of salt saved drops blood pressure by a small but measurable amount.