By Flor Cianchetti


It's okay to enjoy a soft drink every once in a while. But drinking lots of soda on a regular basis could be harmful for your kidneys, according to a recent study.


Healthy kidneys filter waste products from the blood and keep other substances like protein in the blood. Proteinuria occurs when protein isn't properly filtered by the kidneys and is found in the patient's urine.


Proteinuria is a sign of chronic kidney disease and other diseases that cause inflammation in the kidneys.




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This recent study showed that people who drank two or more sodas a day were at greater risk of developing proteinuria compared to those who did not drink as much soda.



This study, which looked at the link between soft drink intake and proteinuria, was conducted by Ryohei Yamamoto, MD, PhD, from the Department of Geriatric Medicine and Nephrology at Osaka University Graduate School of Medicine in Japan, and colleagues.


These researchers analyzed data collected during the annual health exams of 12,026 employees at Osaka University Health Care Center between April 2006 and March 2011. Of these, 7,976 employees (66.3 percent) with normal kidney function were selected.


The 7,976 participants (average age 33, 50 percent male) with no signs of kidney malfunction answered a questionnaire regarding their daily soft drink intake, and proteinuria was assessed on a yearly basis from their first annual physical examination to March 2012.


The study reported that among these participants, 3,579 did not drink soda on a daily basis, 3,055 drank one soda daily, and 1,342 drank more than two sodas per day.


The researchers found that some of the participants developed proteinuria during the observation period, which usually lasted between 1.5 years to 4.0 years. More specifically, 8.4 percent of the participants who did not drink soda, 8.9 percent who drank one soda daily and 10.7 percent who drank more than two sodas developed proteinuria during the median 2.9 years period of observation.


When the authors used statistical methods to estimate the rate of proteinuria among the three groups of participants (0, 1 and 2 or more drinks), they found that individuals who drank two or more sodas per day had a 1.28 times greater rate of proteinuria compared to those who did not drink any soda.


The researchers did not find significant differences between those who did not drink soda compared to those who drank one soda per day.


Dr. Yamamoto further explained to dailyRx News, "Annual health examinations are mandatory in Japan. In future work, we will report results of longer observational periods. However, I believe that we'll observe a similar trend."


He concluded, "Overconsumption of soft drinks can potentially cause damage to your kidneys. Our study that included nearly 8,000 Japanese people revealed that consuming two or more soft drinks per day is a risk factor for proteinuria, a pivotal marker of kidney damage."


This study was presented on November 9 at the American Society of Nephrology's Kidney Week[4] in Atlanta, Georgia.



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  • Heart Attacks


    This week, researchers from the Harvard School of Public Health found that drinking just one sugar-sweetened beverage a day was associated with a 20 percent bump in a man's risk of having a heart attack over a 22-year period. What's more, that risk increased along with the amount of sugary drinks consumed -- even after researchers controlled for other factors like family history, tobacco use and BMI. <a href="http://vitals.msnbc.msn.com/_news/2012/03/12/10656108-soda-drinking-men-at-higher-risk-for-heart-attack?ocid=twitter" target="_hplink">Reported</a> NBC:

    <blockquote>And while link doesn't absolutely prove that sugary drinks increase the risk of heart disease, there is evidence from other studies showing that these beverages have an impact on risk factors, [lead author Lawrence] de Koning said. In one study, for example, volunteers who decreased sugary soda consumption experienced a reduction in blood pressure levels, he added.</blockquote>
    The researchers used data from the longitudinal Health Professionals Follow-up study -- a long-term research project that tracked the health behaviors of 42,883 men over 22 years. Of the entire cohort, a total 3,683 had either fatal or non-fatal heart attacks.

    Previous analysis of long-term research, such as data from the Nurses' Health Study, <a href="http://www.ncbi.nlm.nih.gov/pubmed/19211821" target="_hplink">show that sugary soda consumption</a> has been individually linked to overall heart disease rates for women as well.

    But before you consider switching to diet soda, research has shown that it, too, has a negative effect on heart attack and stroke: a <a href="http://www.msnbc.msn.com/id/46431225/ns/health-diet_and_nutrition/t/daily-diet-soda-tied-heart-attack-stroke/#.T1_HQHLOzDW" target="_hplink">separate study</a> of 2,600 adults found that those who drank diet soda regularly were 40 percent more likely to have a heart attack or stroke.




  • Metabolic Syndrome And Fatty Liver Disease


    Even if it doesn't cause weight gain, sugary soda may be damaging your cardiovascular health -- especially if you're a woman. That's because women who drink sugar sweetened beverages are more likely to develop high levels of triglycerides -- a fat found in the blood stream that can indicate <a href="http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0004546/" target="_hplink">metabolic syndrome</a> at high levels. In a review of data from a large, long-term study of the heart health of both men and women, the Multi-Ethnic Study of Atherosclerosis, <a href="http://www.sciencedaily.com/releases/2011/11/111113141252.htm" target="_hplink">researchers found</a> that women who drank at least two sugary drinks per week were four times as likely to have dangerously high trigylceride levels as those who drank only one sugary drink.

    How does it work? The excess sugar from soda and other drinks is converted in the body to fat. But unlike the subcutaneous fat that's visible under the skin, much of this sugar transforms into either triglycerides or fatty tissue that surrounds organs, like the liver. And both metabolic syndrome and fatty liver disease can contribute to higher risk of coronary heart disease, Type 2 diabetes and stroke.




  • Weight Gain


    Naturally, consuming extra calories from added sugar will lead to weight gain. But even diet soda may lead to unhealthy pounds. While the research is not yet conclusive, recent data demonstrated an association between regularly drinking diet soda and larger waist lines.

    <a href="http://www.huffingtonpost.com/2011/06/29/diet-soda-weight-gain_n_886409.html" target="_hplink">Wrote</a> HuffPost Healthy Living's own Amanda L. Chan:

    <blockquote>A study presented at an American Diabetes Association meeting this week shows that drinking diet soda is associated with a wider waist in humans. And a second study shows that aspartame -- an artificial sweetener in diet soda -- actually raises blood sugar in mice prone to diabetes.

    "Data from this and other prospective studies suggest that the promotion of diet sodas and artificial sweeteners as healthy alternatives may be ill-advised," study researcher Helen P. Hazuda, Ph.D., a professor and chief of clinical epidemiology at the University of Texas Health Science Center San Antonio's School of Medicine, said in a statement. "They may be free of calories but not of consequences."</blockquote>
    An observational study and an experiment in rodents does not make for a lock-tight association, but it's enough to raise cause for concern.




  • Osteoporosis


    An ingredient in cola could be leaching calcium from your bones.

    <a href="http://www.tuftshealthletter.com/ShowArticle.aspx?rowId=23" target="_hplink">One study</a> from Tufts University researchers found that women who reported drinking just three colas a week had an average 4 percent more bone loss at important sites in the hips than women who drank any other beverage -- including non-cola, sugary drinks and sodas. But why?

    Both diet and full-sugar cola contain the flavoring phosphoric acid. According to the study's lead author, Kathleen Tucker, that causes greater acidity in the blood. "At that point, your body's first priority is to restore a balance, so it leaches some calcium out of your bones to neutralize the acid," she told <a href="http://www.thedailybeast.com/newsweek/blogs/the-human-condition/2009/05/22/by-the-numbers-the-truth-behind-those-scary-diet-soda-myths.html" target="_hplink"><em>The Daily Beast</em></a>.




  • Type 2 Diabetes


    Diabetes goes hand-in-hand with obesity and heightened sugar consumption, so it's no surprise that drinking full-sugar soda is associated with the disease.

    The Nurse Health Study data on 90,000 adult women <a href="http://www.ncbi.nlm.nih.gov/pubmed/15328324" target="_hplink">revealed</a> that those who drank one or more sugary soft drinks (such as soda or juice) were also twice as likely to develop Type 2 diabetes. And a <a href="http://www.ajcn.org/content/94/2/479.abstract" target="_hplink">separate study</a> reveals why: sugary drinks increase the level of fasting glucose and insulin resistance -- two signs of pre-diabetes.

    <a href="http://www.sciencedaily.com/releases/2011/06/110627183944.htm" target="_hplink">Initial studies in mice</a> even find that heightened consumption of the aspartame in diet soda can have an ill effect on fasting glucose levels, though that research is not yet conclusive.




  • Half of Americans Drink Soda Every Day


    About half of Americans who participated in a study done as part of Gallup’s annual Consumption Habits poll claimed that they drink at least one glass of soda per day. Even though soda drinks have no nutritional value and are choc full of sugar and sodium, the same number of non-soda drinkers, about 4 out of 10, said that they are overweight compared to the same number of people who drink soda daily.