Put Down That Coke – Your Kidneys Will Thank You For It

Alan McStravick for redOrbit.com – Your Universe Online

The subject of late night comedian’s derision for several months, Mayor Michael Bloomberg’s New York City-wide ban on large sodas met an untimely end in March of this year, just days before it was to have gone into effect.

The UK is proposing a tax increase of 20 percent on sodas, claiming the move will stem the tide of heaviness in their country by as many as 285,000 of their citizens. Additionally, they believe they will reduce the total number of obese Britons by 180,000. We learned last week that not everyone is convinced the tax will have any effect on Britain’s obesity rate.

The proposal, offered up by researchers at Oxford and Reading Universities, is not quite to the policy stage yet. That team hopes their findings will stir curiosity and steel resolve among House of Commons legislators.

While achieving and maintaining a healthy weight has been the primary goal behind the Bloomberg ban and the proposed British tax, much attention has been focused lately on the particularly dire health effects the consumption of sugary sodas can bring upon you. With an article entitled ‘Are Soft Drinks As Bad As Cigarettes For Your Health,’ the Indian website Health listed a litany of negative consequences one could expect from just one of these beverages.

“Did you know that drinking even one soft drink (350ml) increases your chances of getting type 2 diabetes by 20 percent? Or that it can also damage your liver and kidney and is likely to cause cancer and dementia?” With a first paragraph like that, you’ve got my attention. The article cites studies out of the Imperial College of London and the University of North Carolina (UNC) for their stunning assertions. Professor Barry Popkin of UNC, speaking to the Sunday Times said, “If there is any item in our food supply that acts like tobacco, it is sugared drinks.”

We now have two new studies that support the findings of other research teams around the world, particularly as it relates to kidney health. The findings of these studies have been presented at this year’s ASN Kidney Week 2013 in Atlanta, GA.

The first study, led by Ryohei Yamamoto, MD, PhD of the Osaka University Graduate School of Medicine, found the consumption of two or more sugary soft drinks per day is linked with the condition known as proteinuria. Proteinuria is an increase in the excretion of protein in urine. When proteinuria occurs, it is widely regarded as a signifier of kidney dysfunction. The study was conducted using more than 12,000 university employees who all presented normal kidney function at the start of the study.

The full group was separated into groups based on their reported soft drink consumption. Over the 2.9 years of follow-up in the study, the group claiming to have consumed zero sodas per day saw 301, or 8.4 percent of the participants develop proteinuria. 272, or 8.9 percent of those in the group claiming one sugary soda a day developed the condition. But the group enjoying two or more beverages per day had 10.7 percent of their cohort developing the detrimental condition.

In another study, led by Agustin Gonzalez-Vicente of Case Western University, the link between even moderate fructose intake and the kidney’s sensitivity to angiotensin II was established. Angiotensin II is a protein specific to the regulation of salt balance. When this sensitivity in the kidney is increased, kidney cells increase the rate of salt reabsorption.

The Case Western Reserve researchers employed the use of laboratory research rats for their study to arrive at their findings.

The team believes this reabsorption increase, resulting  from high-fructose corn syrup consumption, may well be associated with contributing to the epidemics of diabetes, obesity, kidney failure and hypertension.

Much like professor Popkin’s assertion above, Robert H. Lustig, M.D. has called for the regulation of sweetened beverages in much the same manner the US Food and Drug Administration regulates tobacco. Lustig is a professor of Pediatrics in the Division of Endocrinology at the University of California, San Francisco (UCSF). Lustig is also the Director of the Weight Assessment for the Teen and Child Health Program at UCSF.

Lustig may have a point, too. The human body, in much the same way it becomes addicted to nicotine, naturally craves sugar because it contains glucose. Glucose, as a source of energy, is essential for normal functioning of the human body. Before the Industrial Age and the advent of crystallized sugars, one could only obtain essential glucose through the consumption of natural sources like fruits.

In an article published on Health.com, Dr. Orlando Gutierrez, a kidney specialist at the University of Alabama at Birmingham said, “We now understand that protein in the urine may be a really early marker for heart disease, stroke and heart failure.”

In the same article, Dr. Anil Agarwal, also a kidney specialist at the Ohio State University stated, “The new study suggests that even individuals with normal kidney function are at risk for damage if they drink too much soda.”

Agarwal continues, saying, “Fructose is sweeter than glucose, and doesn’t cause feelings of satiety.” As most soft drinks are sweetened using high-fructose corn syrup rather than glucose, many experts believe it is for that reason soft drinks may be so very dangerous. Agarwal commented that fructose may be responsible for damage by way of a different pathway than glucose. Instead of increasing blood sugar level like glucose does, it affects the kidneys instead.

“There is no safe amount of soda,” he said. “If you look at the recommended amounts of sugar we can safely consume every day, one can of soda exceeds that maximum level.

While experts in endocrinology believe the findings of these two latest studies add to a growing body of evidence against sugary soda consumption, it is important also to realize each study was only able to show an association between possible kidney damage and soda consumption. Neither study can definitively prove soda is the reason behind the increased protein levels.

The last paragraph may be, for some readers, the off-the-hook they were looking for to continue filling up their Big Gulps and stocking their refrigerators with Dr. Pepper. But one thing is certain above all else. Increasing your water consumption to the recommended adequate intake can only ever be beneficial.