In the annals of nephrology, Jalisco holds a dubious distinction: the highest rate of end stage renal disease in Mexico.
And recently, shocking new information about over-the-top soft drink consumption by kids in Mexico, where there is a special name – “cocacoleros” – for people hooked on the popular beverage, suggests a link between soda drinking and the high rate of renal failure.
An example of high incidence of kidney problems, the town of Poncitlan, east of Chapala, has long been considered a cauldron of ill health due to residents’ kidney problems (Guadalajara Reporter, June 16). And renal disease in many nearby communities, including Guadalajara, has put this state on the map among nephrologists.
At the same time, refresco consumption has also come under scrutiny, resulting in a controversial tax imposed in 2013. Then, the recent announcement (Guadalajara Reporter, August 5) by Congresswoman Soledad Sandoval Martinez stating that seven out of tenMexican children start their day with a bottle of soda pop set off more alarm bells. The legislator’s assertions are backed up by other experts, such as Dr. Salvador Villalpando of a Mexico City children’s hospital, who told the BBC that “10 percent of kids are being fed soda from zero to six months of age,” a sad statistic linked with another of Mexico’s distinctions: it has one of the highest child obesity rates in the world.
Obesity is firmly linked with diabetes and, from there, with kidney disease. But, considering the confusing array of data, can one draw a clear line between Mexicans’ excessive soda consumption and their elevated incidence of kidney disease?
At least one piece of this puzzle, the soaring rate of renal problems in Jalisco, is undisputed and, in fact, has made the state infamous among nephrologists.
“Taiwan, the Jalisco region of Mexico, and the U.S. continue to report the highest incidence of treated ESRD [end stage renal disease],” said the U.S. Renal Data System—the gold standard in epidemiology—in 2016. Two other nations and “the Jalisco region of Mexico reported the highest proportions” of kidney disease linked to diabetes, a Canadian medical journal pointed out in 2014. ESRD, in its advanced or “end” stages, requires expensive hemodialysis treatment and, even with treatment, the patient’s life span is generally shortened.
According to nephrologist Dr. Jose Luis Montañez, medical coordinator for a German hemodialysis clinic in Tala, west of Guadalajara, while good reporting from Guadalajara’s Centro Médico explains why kidney disease in Jalisco stands out worldwide, he emphasizes that the problem affects all of Mexico and is indeed enormous. At the clinic in Tala, an agricultural town with a population of just 56,000, about 30 patients a day undergo the three-hour procedure, which they usually repeat several times a week. Dr. Guillermo Garcia, the chief nephrologist at Guadalajara’s Hospital Civil who has been involved in treating Poncitlan residents, says he and University of Guadalajara personnel have seen protein in the urine (indicating renal problems) in 40 percent of children in the area.
But the underlying reasons for kidney failure are not as clear as its rate; they are still something of a mystery. This uncertainty is created by many factors. One is that, according to Garcia, exposure to risk factors occurs over many years. More confusion is due to so many causes having been identified, including new, “nontraditional” ones.
Some of these, according to Garcia, are “low birth weight in babies, water-borne infections leading to diarrhea (causing dehydration), and exposure to pesticides and herbicides, which we know are toxic but we don’t know if they cause the problems in Poncitlan.”
“The cause of renal disease in Mexico is not completely understood,” explains Montañez. “It may be partly genetic. Also, our sedentary lifestyle can cause kidney problems, plus taking unprescribed NSAIDS, like aspirin and ibuprofen. Or minerals in the water, such as lead.”
Dietician Mathea Ford unequivocally calls soda pop a “huge contributing factor to the rising number of people with diabetes and kidney failure.” Dr. Montañez, when asked if soda pop is implicated in renal failure, was willing to add it to the list of villains.
“Drinking refrescos, especially dark ones, is associated with kidney stones,” which in turn are associated with ESRD, Montañez said. The medical journal “Epidemiology” backs him up in an article “Carbonated Beverages and Chronic Kidney Disease,” noting that “cola beverages, in particular, contain phosphoric acid and have been associated with urinary changes that promote kidney stones and drinking just two colas per day is associated with increased risk of chronic kidney disease.”
Dr. Garcia, while not willing to call the cause of ESRD a “mystery,” instead said its causes were “multifactorial.” Based on his experiences in Poncitlan, he put heavy blame on the well-established mercury-contaminated fish, well water contaminated by heavy metals, and poverty.
“It could be refrescos too, if people in rural areas drink a lot of them.”
They do, according to activist Enrique Lira, who drives to Poncitlan frequently, using his background in chemistry and his humanitarian instincts to help the many area residents who are afflicted with renal disease, which he says is sometimes seen in babies who are only 1 1/2 years old.
“They are the most marginalized people in Mexico. The area is inundated with waste from hundreds of factories. Many scientific tests of wells show they contain dangerous metals, chemicals and bacteria, but people drink the water anyway because otherwise they would die of thirst. They eat fish from Lake Chapala, which have tested positive for mercury, because they don’t have money for other food. But sometimes they still manage to drink sodas!”
Montañez has noticed that some causes of renal problems may be specific to rural areas. “In Tala, they burn sugar cane after the harvest and this may introduce harmful substances into the water table, which is quite high there.”