The Mona Lisa – Leonardo Da Vinci’s portrait of Lisa Gherardini – is arguably the most famous painting in the world. Completed around the year 1516, the depiction of a wealthy Florentine silk merchant’s wife was first put on display in the court of King Francis I of France and has been in the public eye ever since it was entrusted to the Louvre in 1797.
In the centuries since, people from around the world have flocked to the museum to see the lady’s enigmatic smile with their own eyes. Naturally, this international attention has fueled a great deal of speculation among historians and art experts about who Gherardini was – as very little is known – and why Da Vinci immortalized her with a look of gentle amusement when all other portraits from the era featured solemn faces.
Not to be left out of the cult of fascination, modern physicians have examined the masterpiece and proposed various lists of ailments that could explain the woman's painted appearance. Now, a research duo led by cardiologist Mandeep Mehra gently refutes past theories while presenting their own diagnosis for the elusive lady.
In a letter to the editor published in Mayo Clinic Proceedings, Dr Mehra and Hilary Campbell explain that Lisa Gherardini’s seemingly yellow-tinged skin, receding hairline, lack of eyebrows or eyelashes, and puffy neck could be a sign of underlying hypothyroidism: a condition wherein the thyroid gland fails to produce normal levels of the metabolism-regulating hormones T3 and T4.
When these crucial hormones are deficient, the liver cannot properly convert carotene – the orange and red pigment found in carrots and other colored vegetables – into vitamin A. The body then deposits the excess carotene in the outer layer of the skin, resulting in a Simpsons-esque glow. On top of weight gain, fatigue, depression, muscle aches, cold intolerance, and a litany of other unpleasant effects, individuals with hypothyroidism experience thinning and coarsely textured hair. Both of the two main causes of hypothyroidism, iodine deficiency and an autoimmune attack on the gland, often lead to an enlarged thyroid or expanding thyroid nodules that can be seen externally. This is called a goiter.
In regards to the painting's beloved smile, the authors posit that a case of advanced hypothyroidism could have led to nerve impairment and facial muscle weakness that prevented Gherardini from smiling completely.
“There are at least two distinct natural history-supporting data that support this diagnosis of hypothyroidism,” Mehra and Campbell wrote. “First, during the Renaissance period, eating habits in Italy were primarily vegetarian, based on cereals, root vegetables, and legumes, and with little meat… [s]eafood was uncommon inland and famine was common. Thus, the diet was one that was often iodine deficient and more importantly, the eating habits promoted the development of goiters.”
The authors further explain that goiter-like neck swellings have been observed in 70 paintings and 10 sculptures also produced during the Italian Renaissance and that recent medical studies have found goiters to be extremely common in Southern Italy to this day.
Dr Mehra’s second piece of evidence is the fact that Lisa Gherardini had given birth to a son just a few months before sitting for the painting. One form of hyperthyroidism onsets during or immediately after pregnancy, and, in many cases, becomes permanent.
A 2004 study had concluded that Gherardini’s appearance may have stemmed from an inherited predisposition toward high cholesterol, but Dr Mehra believes the resulting atherosclerosis would have made it nearly impossible for her to have lived to the ripe age of 63, as records indicate.
“In summary, we believe that the enigma of the Mona Lisa can be resolved by a simple medical diagnosis... In many ways, it is the allure of the imperfections of disease that give this masterpiece its mysterious reality and charm.”
Of course, they also freely admit that their diagnosis could be way off. For example, the skin tone could simply reflect yellowing of the oil paints and varnish over time, and the appearance of the hair could reflect intentional styling whims of the period.