Doctor’s Tip: Chronic kidney disease common but not normal
Each of your two kidneys has around a million filtering units, called glomeruli, which filter about 200 quarts of blood a day. Your kidneys maintain water balance in the body; help maintain normal blood pressure; get rid of urea, uric acid, toxins, and other wastes via urine; activate vitamin D, which helps the body absorb calcium; maintain normal body pH; maintain balance of electrolytes such as potassium, sodium and calcium, which is critical for normal heart rhythm; and release erythropoietin, which tells bone marrow to make red blood cells.
Because of the amazing functions the kidneys perform automatically, we used to have a saying in medical school that “the dumbest kidney is smarter than the smartest doctor.”
The kidneys have millions of small blood vessels, associated with the glomeruli. So when the endothelial lining of arteries is damaged, the kidneys are affected along with the heart, brain and other parts of the body. The factors that damage the endothelium include smoking, high blood pressure, high cholesterol, diabetes and pre-diabetes, lack of exercise, inflammation and the S.A.D. (Standard American Diet, which is high in meat, dairy and fat).
Another factor that causes kidney damage is animal protein, but not plant protein. In his book “How Not to Die,” Michael Greger, M.D. explains why:
1High animal protein intake induces a state in the kidneys called hyperfiltration. Within hours of eating meat, fish, dairy or eggs, the kidneys are stressed. This isn’t a problem if it occurs only occasionally, but we did not evolve to be able to handle the amount of daily animal protein people on the S.A.D. eat (all the hype about more protein being better has no scientific basis).
2However, plant protein is handled differently by the kidneys, and it does not stress them. This is because plant-based diets are anti-inflammatory, whereas animal-based diets cause harmful inflammation.
3Animal-based diets are acidic, while plant-based diets are alkaline. Acid diets are thought to damage the delicate glomeruli.
The first sign of kidney damage is leakage of protein into the urine. The most sensitive test for this is the microalbumin-creatinine ratio, a simple and inexpensive urine test that can be done in most doctors’ offices. The ratio should be less than 4 in men and 7.5 in women. People with risk factors for chronic kidney disease (CKD) such as diabetes/pre-diabetes or atherosclerosis should have this test performed at least annually. Another kidney test is the GFR (glomerular filtration rate), part of most chemistry panels including health fair labs. If the GFR is less than 60, you have CKD.
A recent study showed that 59 percent of Americans have CKD, but most haven’t been told by their providers. This is unfortunate, because CKD can cause high blood pressure, and is a major risk factor for heart attacks and strokes, the major cause of death (heart attacks) and disability (strokes) in the U.S. People with mild CKD have no symptoms, but it tends to progress and when the GFR gets below 10-15, waste products build up and symptoms occur, requiring dialysis or transplant.
Like any vascular disease, CKD can be treated and in some cases even reversed. Here’s how:
1Avoid more than occasional analgesics such as acetaminophen and ibuprofen, and other pharmaceuticals and supplements that can damage kidneys further.
2Be kind to your vascular system: Keep your blood pressure at goal (less than 120/80); don’t smoke; prevent, treat or reverse pre-diabetes and type 2 diabetes (possible through lifestyle modification); keep your cholesterol at goal; exercise regularly; eat more plants and less or, better yet, no animal products. I have seen mild to moderate CKD resolve just with plant-based, whole (unprocessed) foods, moderately low fat nutrition.
3If you have hypertension, vascular disease or diabetes/pre-diabetes, request regular tests for kidney function such as GFR and microalbumin-creatinine ratio, and talk to your provider about taking an ACE inhibitor, which has been shown to protect the kidneys.
Dr. Feinsinger, who retired from Glenwood Medical Associates after 42 years as a family physician, now has a nonprofit Center For Prevention and Treatment of Disease Through Nutrition. He is available for free consultations about heart attack prevention and any other medical concerns. Call 970-379-5718 for an appointment. For questions about his columns, email him at firstname.lastname@example.org.
Start a dialogue, stay on topic and be civil.
If you don't follow the rules, your comment may be deleted.
The Forest Service plans to replace the Carbondale Aspen-Sopris ranger district station with a newer, larger facility.