Women are more sensitive to salt than men and this propensity to retain salt can make them prone to high blood pressure (HTA).
- Women are more sensitive to salt than men. Their body retains more sodium which can affect their blood pressure.
- This phenomenon could be linked to a hormone called aldosterone.
- Researchers call for identifying hypertension thresholds specific to women, as there are differences with men.
Women are often presented as better protected against cardiovascular disease than men until menopause. “The reality is that women and men regulate blood pressure differently and our blood pressures are different to begin with”explains Dr. Eric Belin de Chantemele, a physiologist at the Vascular Biology Center of the Medical College of Georgia at Augusta University.
In its latest study published in the journal Hypertension, it shows that the fairer sex is more sensitive to salt. Moreover, this propensity to retain more salt – a factor in increasing blood pressure – is amplified after menopause.
HTA: women retain more salt
The scientist and his team reviewed several studies concerning the cardiovascular health of women as well as other trials conducted on mice. They put forward that the fairer sex is more sensitive to salt than men. That is, their body has a natural tendency to retain salt rather than excrete the excess through urine. Studies show that menopause exacerbates both the severity and the prevalence of the phenomenon.
“Salt sensitivity is one of the main factors of hypertension (HTA, editor’s note). And, if you look at people who have treatment-resistant hypertension, which is most people, the most are sensitive to salt”explains Dr. Belin de Chantemele. “It is very important to know the cause.”
Different tests have shown that women’s kidneys excrete sodium very well. Thus, the researchers suggest that their sensitivity to salt could be linked to high levels of the hormone aldosterone. It is produced by the adrenal gland and has a direct effect on blood pressure by regulating the salt-water balance in the body.
“High levels of aldosterone are known to contribute to bad things in the body, like widespread inflammation, stiff and scarred blood vessels, and even an enlarged heart”specify the authors in their communicated. They add that in women, the hormone is mainly “harmful to blood vessels, including their significant ability to expand to accommodate more blood volume in response to the retention of more salt”.
For the scientists, their discovery supports another postulate emerging among health professionals. He suggests that the XX sex chromosome predisposes women to salt sensitivity, possibly because they need to nearly double their fluid volume during pregnancy. Estrogen helps to mitigate some of the associated increased risk, at least until its levels drop after menopause.
Hypertension: a different threshold is needed depending on the gender
This difference in salt sensitivity observed in women also highlights the problem of research that is mainly focused on men. “Working primarily on male humans and animal models fuels the misconception that women are less sensitive to salt”write Dr. Belin de Chantemele and her colleagues, Dr. Jessica Faulkner and Candee T. Barris.
For them, it is important to establish gender differences in the regulation of blood pressure. “Although women’s blood pressure tends to be lower than men’s, that doesn’t necessarily mean their pressures are good. Because although the current guidelines have the same healthy blood pressure range for both genders, it appears that women experience damage at a lower threshold or pressure”, they write.
“Women tend to start out with lower pressure, so it is assumed that they are not hypertensive, but, particularly after menopause, pressure increases can be much greater in them”warns Dr Belin de Chantemele.
Scientists recommend determining a lower hypertension threshold for women.
“If we had a different threshold, we would notice pressure changes more quickly, so we could hopefully intervene more quickly”concludes the expert.