Obesity is not only associated with an increase in morbidity, mortality and reduced life expectancy but also leads to the increased incidence of diabetes, hypertension, high lipids leading to increased risk for heart attack and strokes. In th Philippines, diabetes has been found to be the number one cause of end stage kidney disease needing dialysis hence it is not surprising that as we increase our weight we also increase the population of people having kidney disease.

The mechanisms by which obesity damage the kidneys are the following : 1) Glomerular hyperfiltration and this is through increase in blood flow brought about by a hormone system controlled by the kidneys ( called the renin-angiotensin aldosterone system) which is markedly activated in obesity. Fat cells are likewise important source of these hormone. This hyperfunction leads to damage in the filtering membrane which filters our blood and produces urine with waste products as well as the tubular system which is where the urine passes before it goes out of our body. This is manifested as proteinuria or leakage of protein in the urine. The greater amounts of protein being leaked out, the greater is the kidney damage hence this should be monitored when one is being treated . Damage to the tubular apparatus likewise will lead to decreased ability of the kidneys to excrete the salt that we are taking in. Hence people with kidney dsysfunction will have to decrease their salt intake. In time, this can lead to higher blood pressure. 2.) Hyperlipidemia which is common in obese patients, contribute to the injuries to the kidney because of the deposition of fats mainly in the mesangial area which is the supporting structure holding the filtering apparatus together. The end result is worsening of the protein leakage later leading to scar formation. Once the scarred area is already more than 50%, symptoms of CKD ( chronic kidney disease) are already apparent. 3. Leptin and other fat derived hormone which plays a critical role in the control of appetite and energy expenditure. These hormones are increased in non diabetic obese subjects and obese type 2 diabetic patients. It was also found to accelerate the scarring within the kidneys. Another important hormone is resistin secreted by fat cells and was found to be increased in type 2 diabetic patients.

Simply put, as the person gets bigger , HYPER - filtration occurs and this over filtration is what tears the kidney apart.

Risk factors currrently recognized to increase the chance of kidney failure include hypertension, diabetes, smoking, family history of kidney disease and increasing age. It is now evident that obesity should be added to that list.