Want to know if a man will take care of his appearance, be polite, laugh more, compliment others or be promiscuous? Or whether a woman is more likely to enjoy professional success or make a greater effort to attract potential boyfriends?

According to scientists you can ascertain these traits and many more by observing the length of a person’s fingers.

More importantly, research shows that finger length also indicates a person’s risk of developing certain health conditions. The most recent study gives clues as to how sick you’ll get after contracting COVID-19.

It seems bizarre that finger length could tell us so much about our personality, behavior, abilities, and propensity to suffer certain illnesses. But more than 1,400 studies over the past 24 years suggest your digits can do just that.

Index and Ring Fingers are Revealing

Different finger proportions between men and women were first reported in the 19th century by a German anatomist. But it took until 1998 for this field of research to take off when evolutionary biologist John Manning, now at Swansea University in Wales, measured finger lengths of patients in a clinic.

He found lower finger length ratios in men’s right hands correlated with higher testosterone levels. The key ratio being between the index finger (2D) and the ring finger (4D).

The differences in ratios between the genders even applied to children as young as two, suggesting differences in the relative levels of testosterone and estrogen in the womb.

It’s now recognized that a longer ring finger is a marker of higher levels of testosterone prenatally, whereas a longer index finger is a marker of higher levels of estrogen. In general, men have longer ring fingers, while women have longer index fingers.

Further research also suggests a short pinky (5D) relative to the middle finger (3D) is indicative of low testosterone especially during puberty. Differences in finger ratios between the right and left hand also provide further clues. (That’s right, take a close look at your hands, the differences in finger length between fingers on your left hand is probably different than the differences in finger length on your right hand.)

Researchers say that it’s these hormone differences that are reflected in our personal characteristics and propensity for disease.

Professor Manning has since written two books and over 60 research papers on the 2D:4D ratio. His latest study investigates the likelihood of being hospitalized with COVID-19.

Older Men at Greater Risk

Since men experienced greater COVID-19 disease severity than women, it’s possible that hormones are implicated. To find out, Professor Manning and research colleagues from Poland and Sweden examined 54 patients and 100 healthy controls, looking not just at the 2D:4D ratio but five other digit length ratios, excluding the thumb. They found patients differed in their digit ratios compared to controls.

Patients with “feminized” short little fingers relative to their other three fingers tend to experience severe COVID-19 symptoms leading to hospitalization, and more importantly patients with sizable differences in right-and left-hand ratios 2D:4D and 3D:5D, have substantially elevated probabilities of hospitalization.

Prof. Manning explained, saying, “Our findings suggest that COVID-19 severity is related to low testosterone and possibly high estrogen in both men and women.

“’Feminized’ differences in digit ratios in hospitalized patients supports the view that individuals who have experienced low testosterone and/or high estrogen are prone to severe expression of COVID-19. This may explain why the most at-risk group is elderly males.”

Since low testosterone and high estrogen prenatally and at puberty has been linked to other conditions such as obesity and heart disease in men, he adds that “COVID-19 is potentially more serious in patients suffering from these pre-conditions.”

  1. https://www.express.co.uk/life-style/life/584757/Secrets-behind-fingers
  2. https://www.science.org/content/article/talk-hand-scientists-try-debunk-idea-finger-length-can-reveal-personality-and-health
  3. https://www.nature.com/articles/s41598-022-08646-7
  4. https://www.swansea.ac.uk/press-office/news-events/news/2022/03/how-fingers-could-point-to-a-link-between-low-testosterone-and-covid-hospitalizations.php