Your kidneys do more than filter waste: Here’s how they help control blood sugar

Wait 5 sec.

Blood sugar is usually discussed in relation to the pancreas, insulin, diet, and physical activity. However, the kidneys also play a surprisingly important role in glucose regulation, even though they are rarely part of the conversation. Beyond filtering waste from the blood, the kidneys help reabsorb glucose, produce glucose during fasting, and influence how excess sugar is handled by the body. The kidneys are active participants in maintaining normal blood sugar levels rather than simply being organs affected by diabetes.DISCLAIMER: This article is based on information from the public domain and/or the experts we spoke to. Always consult your health practitioner before starting any routine.This raises an interesting question: can subtle changes in kidney function influence blood sugar even before someone develops chronic kidney disease? Since diabetes is one of the leading causes of kidney disease, discussions often focus on how high blood sugar damages the kidneys. But the relationship appears to work both ways. Changes in kidney physiology, hormone signalling, glucose reabsorption and filtration may affect blood sugar regulation long before a person is diagnosed with kidney disease. Understanding this two-way connection could help people appreciate why protecting kidney health is an important part of maintaining overall metabolic health.The kidneys’ role in blood sugar regulationKanikka Malhotra, Consultant Dietician & Diabetes Educator, tells indianexpress.com, “This is something I wish more people understood. Healthy kidneys aren’t just filtering waste; they’re actively involved in glucose regulation through a process called renal gluconeogenesis, where kidney tissue actually produces glucose, and through glucose reabsorption, where the kidneys reclaim filtered sugar back into the bloodstream rather than letting it pass into urine.”Under normal conditions, Malhotra notes that this reabsorption is tightly regulated by transporters called SGLT2, which is actually why an entire class of diabetes medications targets the kidney directly. “Even before any diagnosable kidney disease exists, subtle shifts in how efficiently the kidneys reabsorb glucose or respond to insulin signaling can nudge blood sugar levels upward. This means the kidneys aren’t just victims of high blood sugar down the line; they’re active participants in glucose balance from the very beginning, quietly shaping how your body handles sugar long before any lab test would flag kidney concern.”The two-way relationship between kidney function and blood sugar“I think this bidirectional relationship deserves far more attention than it gets,” stresses Malhotra, adding that even mild reductions in kidney efficiency, well before someone would be diagnosed with chronic kidney disease, can alter how the body clears insulin, how sensitive tissues are to insulin’s signal, and how much glucose the kidneys reabsorb rather than excrete. When kidney function starts to dip even slightly, insulin tends to linger longer in circulation since the kidneys play a role in breaking it down, which can quietly promote insulin resistance over time.At the same time, she adds that early changes in kidney filtration can alter sodium and fluid balance in ways that indirectly stress glucose metabolism. So the relationship isn’t one-directional; poor blood sugar doesn’t just damage kidneys over years. Early kidney inefficiency can also set the stage for worsening glucose control, often silently, long before either condition shows up on a standard screening panel.Story continues below this adSupporting kidney health and healthy blood sugarQuick QuizSee if you can answer this:Which habit helps protect both kidney health and healthy blood sugar?A. Eating a very high-protein diet regardless of kidney health.B. Staying active, reducing excess sodium and ultra-processed foods, keeping well hydrated, and monitoring blood pressure and kidney function if you’re at higher risk.C. Drinking more water while continuing a sedentary lifestyle.D. Waiting until kidney symptoms appear before getting tested.Reveal the answer✅ Correct answer: BStory continues below this adMalhotra mentions that the habits that support healthy blood sugar also protect your kidneys. Staying well hydrated, limiting excess sodium and ultra-processed foods, exercising regularly, and avoiding long periods of sitting all benefit both. Protein intake should be adequate but not excessive, particularly for people with existing kidney disease. Those with prediabetes, high blood pressure, or a family history of kidney disease should also have regular kidney function and urine tests, as early changes can often be detected long before symptoms develop.DISCLAIMER: This article is based on information from the public domain and/or the experts we spoke to. Always consult your health practitioner before starting any routine.