---
title: "Health survival paradox"
chunk: 2/3
source: "https://en.wikipedia.org/wiki/Health_survival_paradox"
category: "reference"
tags: "science, encyclopedia"
date_saved: "2026-05-05T03:57:59.615345+00:00"
instance: "kb-cron"
---

==== Genetic factors ====
The female sex has two X chromosomes that can protect against expression of recessive genes and allows a female survival advantage. A research study conducted on flies indicated that the alleles that contribute to male inclusive fitness also harm female health, and thus contribute to the paradox.

==== Physiological factors ====
It is also a possibility that the female hormone, estrogen, contributes to the female survival advantage. In cutaneous melanoma, estrogen was evaluated to determine its effect on a steroid hormone-sensitive cancer. While no difference in survival was concluded between two genders due to limited data, women tend to have better prognosis due to the presence of estrogen receptor beta. However, this is a continued study that may be due to biological factors—such as immune response, inflammation, pharmacokinetics, or hormones—or from social factors—such as women tending to have more ultraviolet protection and frequent medical visits.
Although studies have shown the protective effects of estrogen on cardiovascular health (i.e. by lowering LDL and increasing HDL) and brain cell health, there are doubts about the role of hormones due to mixed results in hormone replacement therapy studies on elderly women. For instance, although lower levels of LDL may prevent atherosclerotic buildup which can lead to chronic heart disease, estrogen may overall elevate chronic heart disease in older women with advanced plaque buildup by causing thrombosis.
Women can store excess high-density lipoproteins, which most likely slows the progression of plaque growth. Interestingly, calcium metabolism may contribute to the female mortality advantage. After age 35, where the human skeleton grows to its maximum size, calcium buildup increases significantly due to constant release from a deteriorating skeleton, less exercise for calcium release via sweating, and continued dietary intake. Consequently, excess calcium deposits in soft tissues, causing stiffening of arteries and higher blood pressure, leading to cardiovascular disease. For women, however, calcium influx can halt or be reversed during pregnancy and lactation. Women can also release calcium via menstrual cycle until menopause.
Women additionally have lower mortality rates in high-mortality conditions like famine and epidemics. In such conditions, most of the advantage comes from differences in infant mortality rates.

=== Social factors ===
Another possible explanation of the paradox is a social expectation of the female sex role, making women more willing to seek medical help sooner. There is mixed evidence on the role of help-seeking and reporting behavior, with some studies reporting that women are more likely to seek and report medical treatment for all symptoms, while others report that women only tend to seek more treatment on malaise-type symptoms.
As child bearers, females face maternal mortality, which peaked between 1900 and the 1930s. At the time, aseptic technique was not widely practiced, including during child delivery, abortions, and associated surgical procedures. Obstetrics was also a poorly regarded medical specialty where practitioners were poorly trained, if at all. In the early 1930s, hospitals in the United States began establishing rigorous physician qualification and practice guidelines to ensure sufficiently trained obstetricians, application of aseptic technique, and safe and effective deliveries. Other medical advancements, including antibiotic use, blood transfusions, and improved medication management during pregnancy, also improved maternal mortality. Collectively, these improvements reduced maternal mortality by 71%. However, the significant decrease in maternal mortality during this period only accounted for 14% of the longevity difference between females and males.

=== Psychological factors ===
A study conducted in the United States (US) consisting of 9,000 participants determined that women have a 1.5 times greater risk of experiencing a mood disorder compared to men. Additionally, a 2006 study examining mental health in New Zealand found that lifetime rates for major depression are higher in women (20.3%) compared to men (11.4%). Not only do women experience a greater preponderance of depression compared to men, they also experience greater severity of symptoms. The symptoms that women experienced with greater severity included weight gain and increased appetite, greater interpersonal sensitivity, and reduced energy. Women also experience onset of depression at an earlier age, and experience more years of depression when compared to men.

== Female survival advantage ==