Eating Fruits and Vegetables Increases Alkalinity, Protecting Kidneys and Heart

Researchers suggest that eating fruits and vegetables should be the first line of treatment for hypertension.

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Eating 2 to 4 cups daily of fruit or vegetables helps lower blood pressure, slows kidney damage, and reduces the risk of heart disease, according to a new study published on Aug. 6 in The American Journal of Medicine.

Most fruits and vegetables have an alkalinizing effect when broken down by our bodies, meaning they help neutralize our bodies’ acidity (pH). Reducing acidity protects blood vessels and kidneys, shielding the kidneys’ filters and blood vessel lining from damage.

Diets rich in produce help lower blood pressure through several mechanisms. Increasing nitric oxide levels improves vascular function and relaxes blood vessels. They are also high in potassium and contain magnesium and calcium. Potassium reduces blood pressure, and magnesium and calcium protect the blood vessel lining.

This protection prevents oxidative stress and inflammation caused by acid buildup, helping reduce the risk of chronic kidney disease and cardiovascular disease.

Similar effects may be achieved by taking sodium bicarbonate or baking soda. Baking soda is the standard treatment for acid buildup in people with chronic kidney disease, which is known to contribute to disease progression.

Acidic Diet Harms Kidneys

Researchers from the University of Texas at Austin conducted a five-year randomized, controlled trial to compare the kidney-protective effects and subsequent heart benefits of reducing dietary acid with fruits and vegetables versus sodium bicarbonate tablets.

They evaluated 153 participants with hypertension and chronic kidney disease. One-third received standard medical care and extra fruits and vegetables, one-third received standard medical care and supplemented their diets with baking soda, and the remaining third received only standard treatment.

The kidneys remove waste from the body, including acidic waste produced by the breakdown of meat and proteins consumed in the diet. People with kidney diseases are often advised to follow a plant-based diet or supplement their diet with baking soda because it eases the burden on already-compromised organs.

Most fruits and vegetables become alkaline in the body. Even highly acidic fruits such as lemons create a significant alkalinizing effect after we eat them.

Lead investigator Dr. Donald E. Wesson of the Department of Internal Medicine at the University of Texas at Austin’s Dell Medical School told The Epoch Times that while the kidneys’ process of removing acid does not cause damage in the short term, it can lead to kidney injury over many years.

“This is what appears to happen when we eat the acid-producing diets of modern societies that contain more animal products than fruits and vegetables,” he said.

Kidney and Heart Benefits

Eating fruits and vegetables and supplementing with baking soda provided similar results, offering additional kidney protection alongside the benefits of hypertensive medications given to all participants.

Both methods significantly slowed kidney damage progression better than standard medical care alone.

By the study’s second year, researchers observed significant findings in the two groups, with an increase in the amount of blood filtered by the kidneys each minute. These improvements were sustained thereafter.

Participants in the fruit and vegetable group ate the following produce:

• Fruits: apples, apricots, oranges, peaches, pears, raisins, and strawberries
• Vegetables: carrots, cauliflower, eggplant, lettuce, potatoes, spinach, tomatoes, and zucchini

When asked why significant results only appeared in the second year, Wesson explained that just as it takes long-term exposure to an acid-producing diet to harm the kidneys, it also takes time for a base-producing diet to show benefits. Additionally, since the team measured kidney outcomes annually, the earliest benefits could have been detected was one year.

All three groups showed lower blood pressure in the first year of the study, owing to the cholesterol-lowering drug all groups received. However, the group that ate fruits and vegetables showed more significant reductions than the others.

In addition, only fruits and vegetables were linked to improved cardiovascular risk parameters, such as lower “bad” cholesterol and body mass index (BMI). These improvements emerged in the first year of intervention and boosted the protection the cholesterol-lowering drugs provided.

Notably, fruits and vegetables yielded these benefits at lower medication dosages, although participants initially took the same dosages as those in the other groups.

Fruits, Vegetables as Foundational Treatment

Diets high in fruits and vegetables have been proven to lower blood pressure in hypertensive patients and are recommended alongside medications for managing high blood pressure. However, doctors typically start treatment with medication, suggesting dietary changes only as an adjunct.

Wesson said that doctors may be reluctant to recommend plant-based diets because patients find them difficult to follow because they are so different from the animal-based Western diets most are accustomed to.

In the study, participants were instructed to add specific amounts of fruits and vegetables to their diets to reduce the acid load on their kidneys by half without being asked to modify their overall diets. Given this, it might be assumed that adding adequate portions of fruits and vegetables would yield similar results. While Wesson believes this to be true, he stated that further testing is needed to confirm it.

He encourages everyone to increase fruit and vegetable intake to lower blood pressure and reap kidney and cardiovascular benefits.

For an easy way to increase fruit and vegetable intake, Wesson suggests adopting structured diets high in fruits and vegetables and low in animal products such as meat. “Common such diets are the Dietary Approaches to Stop Hypertension (DASH) diet and the Mediterranean diet,” he said.

Dr. Joshua Barzilay, an endocrinologist with the Southeast Permanente Medical Group and adjunct professor at Emory University School of Medicine, who was not involved in the study, agrees on the importance of a good diet.

He told The Epoch Times via email, “Any dietary modification that reduces highly processed intake and focuses on nature’s foods will be beneficial.”

He said that refined foods increase harmful compounds called advanced glycation end products (AGEs), which form when protein or fat combine with sugar in the bloodstream. AGEs increase inflammation and oxidative stress and are linked to chronic diseases such as kidney and heart disease.

In addition to promoting a heart- and kidney-healthy diet, the researchers also advocate routine screenings for albumin in the blood of people with hypertension since high albumin can be a sign of kidney damage and cardiovascular disease progression. Despite many studies supporting it as a biomarker for disease risk, it is still underused by many clinicians.

The researchers stated that routine albuminuria measurement in people with hypertension will help identify underlying chronic kidney disease and their risk for kidney function decline and cardiovascular disease. Barzilay added, “By not screening for albuminuria, there is a missed opportunity for early prevention.” He noted that early detection allows preventive measures to slow chronic kidney disease progression.