Does Your Diet Protect or Damage Your Kidneys?

Your kidneys are important. While you sit reading this, they are receiving 24% of your cardiac output. That fact tells you they are extremely important.  Not only do they make urine, they help to balance your body’s chemistry, produce the active form of vitamin D, and help regulate your blood pressure.

Chronic Kidney Disease

Do you have diabetes, hypertension, obesity, or rheumatoid arthritis?  If so, you are at significant risk for chronic kidney disease (CKD). Kidney disease affects 10 percent of the U.S. population — more than 25 million people. Less than 20% of individuals who have CKD are aware that they do. Unfortunately, poor kidney function has been strongly linked to decreased blood flow to the brain. It has also been linked to stroke and dementia!¹

Stay Away from Red Meat, Especially Pork

Red meat intake may increase the risk of kidney failure in the general population. Fortunately, substituting red meat with alternative sources of protein from time to time may significantly reduce this risk. This study included 63,257 Chinese adults in Singapore. This is a population where 97% of red meat intake consists of pork. Other food sources of protein include poultry, fish/shellfish, eggs, dairy products, soy, and legumes. After 15 1/2 follow-up years, the researchers found that people consuming the highest amounts (top 25%) of red meat had a 40% higher risk of developing end-stage renal disease than those consuming the lowest amounts (bottom 25%). No link was found with poultry, fish, eggs, or dairy product intakes. Consumption of soy and legumes appeared to be slightly protective. If you are at risk for kidney disease, avoid consuming pork and red meat at all costs! ²

Meat consumption has also been linked to kidney cancer. Kidney cancer patients consumed more red and white meat compared to healthy individuals. Diets high in meat may increase the risk of developing renal cell carcinoma (RCC) through the intake of carcinogenic compounds created by specific cooking techniques, such as barbecuing and pan-frying.³

Follow the DASH Diet

Originally designed to help individuals with hypertension, the DASH diet can lower one’s risk for kidney disease. Researchers studied 15,792 middle-aged adults from Maryland, North Carolina, Minnesota, and Mississippi communities for more than 20 years. Here is a summary of their findings: ⁴

• People who ate a diet high in nuts and legumes, low-fat dairy, whole grains, fruits and vegetables, low in red and processed meat, few sugar-sweetened beverages, and low sodium were at a significantly lower risk of developing chronic kidney disease over the course of more than two decades.
• Participants with the lowest DASH diet scores (those who ate few foods such as fruits, vegetables, and nuts, and consumed more red meat and sodium) were 16 percent more likely to develop kidney disease than those with the highest DASH scores (those who ate more of the healthier foods and less of the unhealthy items).
• Those who had the highest intake of red and processed meats were at a 22 percent higher risk of developing chronic kidney disease than those with the lowest intake of those foods.
• Those with the highest intake of nuts and legumes were at a 9 percent lower risk of developing kidney disease than those with the lowest intake of nuts and legumes.

Emphasize Alkaline Foods

For individuals with chronic kidney disease (CKD), studies have shown that diet can significantly influence the risk of progression to kidney failure.  In one study, participants with CKD who consumed high-acid diets were 3-times more likely to develop kidney failure than patients who consumed low-acid diets. Low-acid diets are rich in fruits and vegetables, while high-acid diets contain more meat. ⁵

Go Easy on the Salt

Excessive salt intake has been consistently linked to worsening kidney function and increased risk for heart disease. Salt intake accelerated kidney scarring in rats with chronic kidney disease.⁶ One study showed that in individuals who had CKD, low salt intake reduced excess extracellular fluid volume by 1 liter, lowered blood pressure by 10 /4 mm Hg, and halved protein excretion in the urine, without causing significant side effects. The study’s author concluded that if a low salt intake was maintained long-term, this could reduce the risk (by 30%) of progression to end-stage kidney disease — where dialysis or a transplant are required to survive. ⁷

Read Food Labels and Limit your Intake of Phosphates

Artificial phosphates added to dairy and cereal products appear to cause bigger spikes in blood phosphorus levels and are more dangerous than naturally occurring phosphates. Phosphates can be preservatives, thickening agents, and leaven. They are found in pancake mixes, quick bread mixes, and processed cheese. The more phosphates people consume, the more likely they are to experience blood vessel changes that can lead to decreased kidney function. Phosphates stress the kidneys. Too much dietary phosphate also stiffens blood vessels. High phosphorus in the blood is associated with increased patient mortality, blood vessel stiffening, and increased calcium deposition rate in heart valves. This calcium comes out of the bones and weakens bones and damages kidneys.⁸

Lose Weight If Obese

Losing weight may preserve kidney function in obese people with kidney disease. Obesity increases the risk of diabetes, hypertension, and kidney disease. A five or ten percent drop in weight may stave off diabetes and help improve blood pressure. Obesity causes kidney cell damage by suppressing an important cellular process, autophagy, that prevents kidney cell damage. ⁹

Autophagy

Autophagy is a degradation system within cells that removes damaged proteins and other defective cellular components. Autophagy insufficiency is commonly seen in obese individuals.

In one study, researchers found that in normal-weight mice with kidney disease, autophagy was active in kidney cells. However, in obese mice with kidney disease, autophagy was suppressed and kidney cells became damaged.¹⁰ Early studies show weight loss attained through diet and exercise reduces proteinuria (protein in the urine—a hallmark of kidney damage) and may prevent additional decline in kidney function in obese patients with kidney disease.¹¹

Disclaimer: The information in this article is helpful and is educational. It is not the authors’ or Wildwood Health Institute’s intent to substitute the blog article for diagnosis, counseling, or treatment by a qualified health professional.

Copyright through December 2023. All rights reserved by Wildwood Sanitarium, Inc. 

Key Words: diet and the kidneys, diet and kidney disease, chronic kidney disease, vegetarian and kidney disease, how to prevent chronic kidney disease, diet and kidney function, alkaline diet and kidneys, diet kidney healthy, diet for kidney health

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2. American Society of Nephrology (ASN). “Red meat consumption linked with increased risk of developing kidney failure.” ScienceDaily. ScienceDaily, 14 July 2016. www.sciencedaily.com/releases/2016/07/160714193627.htm[↩]
3. Stephanie C. Melkonian SC. Gene-environment interaction of genome-wide association study-identified susceptibility loci and meat-cooking mutagens in the etiology of renal cell carcinoma. Cancer, 2015; DOI: 10.1002/cncr.29543[↩]
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9. American Society of Nephrology (ASN). “Obesity suppresses cellular process critical to kidney health.” ScienceDaily. ScienceDaily, 3 October 2013. www.sciencedaily.com/releases/2013/10/131003204946.htm[↩]
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11. American Society of Nephrology. “Weight Loss Is Good For The Kidneys, Study Finds.” ScienceDaily. ScienceDaily, 18 September 2009. www.sciencedaily.com/releases/2009/09/090917191559.htm[↩]