5 Reasons Why Palo Azul Can Promote Kidney Health

palo azul vs kidney stones

Palo azul "significantly lowered growth rate of kidney stones"

For centuries, people have been drinking palo azul tea to maintain healthy kidney function. In fact, palo azul is commonly known as "kidney wood" or "kidney tea" because of its popularity for kidney health.

Recently, numerous studies have demonstrated that palo azul’s beneficial effects on kidney stones are due to its powerful diuretic, antioxidant, alkalinizing and anti-bacterial properties. Therefore, the studies have supported palo azul’s efficacy for its traditional use of promoting kidney health.

kidney stones

For example, a 2004 study found that palo azul’s “isoflavones (antioxidants) showed a marked inhibitory activity on crystal aggregation.” The researchers concluded that palo azul’s extracts “work as inhibitors in the formation and crystal growth of calcium oxalate (kidney stones), reducing the degree of aggregation and the size of particles precipitated.”

Calcium oxalate crystals are the most common cause of kidney stones. These crystals are made from oxalate — a substance found in foods like green, leafy vegetables — combined with calcium.

Moreover, a 2002 study found that palo azul “significantly lowered growth rate and nucleation rate of calcium oxalate crystals (kidney stones)” and the researchers concluded that palo azul “showed significant dose dependent protection against urolithiasis.” Urolithiasis is the formation of kidney stones.

palo azul antioxidant

1. Antioxidant

A 2022 study found that palo azul “significantly reduced oxidative damages in both the kidneys and the liver, and such effect has been related to the high antioxidant capacity of the characterized phytochemicals.”

“Phyto” means “plant”, and phytochemicals are micronutrients produced by plants to fight off infections, oxidative stress and inflammation. These include flavonoids and polyphenols, and numerous studies have shown that palo azul is rich in phytochemicals.

A 2022 study even mentions that several types of phytochemicals have been found in palo azul, including “polyphenols, flavonoids, phytosterols, saponins, alkaloids, and terpenoids, which could be effective in preventing the process of stone formation.”

polyphenols flavonoids family tree

A 2021 study which supports these findings mentions that “palo azul is used in traditional medicine for the treatment of kidney diseases, bladder infections and diabetes mellitus.”

The researchers also found several phytochemicals in palo azul such as “flavones, isoflavones, flavanones, phenolic compounds, chalcones, dihydrochalcones” which have been linked to its health benefits, highlighting “diuretic, antidiabetic, antiglycation, antioxidant, anti-inflammatory, antimicrobial potential.”

kidney stone sizes

A quote from this 2007 study demonstrates the beneficial effects of palo azul’s phytochemicals: "A significant decrease in urinary stone size was observed in animals treated with palo azul’s isoflavones.” The researchers concluded that palo azul’s compounds “may surely help in decreasing the recurrence rate of renal calculi.”

2022 study explains why antioxidants and anti-inflammatories are key for preventing kidney stones:

"Among the molecular mechanisms involved in the formation of urinary stones are inflammation and oxidative damage caused by oxidative stress (OS). During OS, there is an increase in the levels of reactive oxygen species (ROS) and a decreased antioxidant system. It is known that inflammation and OS facilitate crystal adhesion to renal tubular cells and crystal formation, promoting kidney stone development. Excessive levels of ROS are important for cellular signaling, including the activation of pro-inflammatory genes expression and impaired endothelial function."

In other words...antioxidants are beneficial for preventing kidney stones because they inhibit inflammation, oxidative stress and ROS, which can facilitate stone formation. 

palo azul vs free radicals

Fortunately for us palo azul lovers, a 2021 study found that palo azul tea "can reduce the oxidative stress caused by the imbalance between reactive oxygen species (ROS) because of its free radical scavenging activity."


palo azul diuretic

2. Diuretic

Many studies have also demonstrated palo azul’s beneficial effects on kidney health because of its diuretic property. This means that palo azul increases diuresis…also known as urinating.

A 2016 study actually found that “the bark of E. polystachya (palo azul) induces an increase on urinary excretion of water and sodium, but with the advantage of a potassium-saving effect.” The researchers concluded that palo azul acts as a “potassium-sparing diuretic and this effect should be viewed as a favorable feature of the extract in regards to electrolyte excretion.”

diuresis urination

Interestingly, since palo azul is a potassium-sparing diuretic, this essentially means that it flushes out toxins without electrolyte loss during urination because it spares potassium...as opposed to aquaretic diuretics like coffee and green tea. 

A 2008 study tested palo azul’s bark for its “antilithiatic and diuretic activity” and the researchers mention thata significant decrease in the weight of stones was observed after treatment in animals that received aqueous extract.”

Antilithiatic is the technical term for preventing the formation of, or relieving the symptoms of kidney stones.


palo azul alkaline

3. Alkaline

Several sources also mention that alkalinity is beneficial for dissolving kidney stones because the stones themselves are acidic.

book about botanical medicine mentions the following: "If prone to acidic, overly concentrated urine, associated kidney stones and urinary tract sediment then Kidneywood (palo azul) will be of use. Because of the plant’s alkalinizing nature, acidic precipitants dissolve back into the urine, thereby reducing pain and urinary tract irritability associated with lithic deposits.

Moreover, a 2007 study did an extensive 77 page analysis on palo azul and found that it has electrolytes that makes palo azul slightly alkaline. Therefore, the researchers found that palo azul "decreases the acidity of urine."

palo azul and alkaline fruits

A 2011 study also mentions that "for prevention of calcium oxalate, cystine, and uric acid stones, urine should be alkalinized by eating a diet high in fruits and vegetables or drinking alkaline mineral waters."

A 2013 study which corroborates these findings, suggests that "ingestion of vegetables high in organic anion content, such as citrate and malate, should be associated with higher urine pH and fewer stones because the amino acid cystine is soluble in more alkaline urine."



palo azul antibacterial

4. Antibacterial

Another one of palo azul’s beneficial properties for treating alleviating kidney pain is its antibacterial activity.

In fact, a 2009 study showed that “palo azul was active against S. epidermidis, Proteus vulgaris, Enterbacter aerogenes and S. aureus. These are the most frequent causal agents of urinary tract infection.” 

2022 study explains that "urinary tract infections (UTI) are common ailments, mainly caused by bacteria such as Escherichia coli." 2018 study even found that palo azul showed good antimicrobial effects in E. coli.”

palo azul vs bacteria

A 2007 study also found that palo azul’s “flavonones have been identified with antibacterial and antifungal activity.” Because of this, recent studies have "evaluated the effect of isoflavones isolated from the bark of palo azul on the growth of urinary crystals confirming the use of the plant in urolithiasis (formation of kidney stones).”

Therefore, the researchers concluded that palo azul is used for “kidney problems, urinary tract pains, kidney calculi, and as a deflamatory.”

kidney stone formation

A 2022 study explains the biological mechanisms of palo azul’s beneficial effects on kidney stones:

“Evidence suggests that (palo azul's compounds) beneficial effects might be associated with litholytic, antispasmodic, and diuretic activities, as well as an inhibitory effect on crystallization, nucleation, and aggregation of crystals (kidney stones). The molecular mechanisms involving these effects could be related to antioxidant, anti-inflammatory, and antimicrobial properties.

Lytholitic is the technical term for the dissolution of kidney stones or gall stones.

Antispasmodics relax the smooth muscle of the ureters and have been shown to hasten stone passage by five to seven days. They relax the muscles in your ureter, helping you pass the kidney stone more quickly and with less pain

Crystallization is the formation of crystals in the kidney. This is normal and harmless provided that they are excreted with the urine. The problem is when the crystals stay behind in the kidneys. 

Nucleation of stone constituent crystals is a mechanism of stone formation.

Aggregation is another mechanism of stone formation in which there is agglomeration of crystals that form into larger multicomponent particles. 

In other words...palo azul's compounds helped to dissolve kidney stones, inhibit stone formation, and relax the ureter muscles to facilitate the passing of the stones.

man with urinary tract pain

The researchers of this 2002 study explain similar mechanisms: “The isolated isoflavones from E. polystachya (palo azul) work as inhibitors in the formation and crystal growth and may protect against stone formation by reducing the degree of aggregation and the size of particles precipitated.”

Lastly, the researchers concluded that “palo azul can be recommended as a preventive medicine in renal stone formation.”


palo azul antidiabetic

5. Anti-Diabetic

Many studies have demonstrated that palo azul is anti-diabetic because it improved insulin sensitivity and blood glucose levels. This relates to kidney health as well because some studies suggest that diabetes can cause kidney damage.

The previously cited 2022 study mentions that "over time, diabetes is a risk factor for chronic kidney disease, and diabetic nephropathy is the most common cause of end-stage renal disease." The researchers say that "the pathophysiology induced by diabetes mellitus develops in multifactorial forms and can even trigger other renal risk factors."

diabetes glucose meter

This is their explanation for the mechanisms by which diabetes and blood pressure can cause kidney damage:

"The kidney has self-regulating mechanisms to dampen fluctuations in systemic blood pressure to avoid an increase in intraglomerular pressure. However, at constant high blood pressure, these kidney mechanisms fail because the incoming vessels become weaker, stiffer, or thinner, and a phenomenon called myogenic reflex occurs. As proteins accumulate in the tubules, they activate profibrotic, proinflammatory, and cytotoxic pathways, causing tubulointerstitial damage and kidney scarring."


In conclusion, palo azul can help to maintain healthy kidney function because it's antioxidant, diuretic, alkalinizing, anti-bacterial, anti-microbial, anti-diabetic, and it's rich in polyphenols and flavonoids. Because of these properties, palo azul's compounds may help to dissolve kidney stones, inhibit stone formation, inhibit bacteria in the urinary tract, and relax the ureter muscles to facilitate the passing of stones.

If you're reading this... I've felt your pain and believe me, you've got little to lose and a lot to gain by trying palo azul tea, even if it just slightly eases your pain.


magiktea palo azul logo

Show your kidneys some love... 

you only got two of them! 😉



urinary stone prevention plants


Clinical Studies

* Palo azul is commonly referred to by its scientific name: Eysenhardtia polystachya / E. polystachya / E.P - Cyclolepis genistoides / C. genistoides - kidney wood - palo dulce


(2022) Plants Used in Mexican Traditional Medicine for the Management of Urolithiasis: A Review of Preclinical Evidence, Bioactive Compounds, and Molecular Mechanisms

(2022) Nephroprotective Plants: A Review on the Use in Pre-Renal and Post-Renal Diseases

(2021) Screening Anti-Inflammatory Effects of Flavanones Solutions

(2013) Optimum Nutrition for Kidney Stone Disease

(2016) Diuretic activity of the bark of Eysenhardtia polystachya

(2011) Treatment and Prevention of Kidney Stones

(2009) Activity of extracts from two Eysenhardtia species against microorganisms related to urinary tract infections

(2008) Antiurolithiatic Activity of 7-Hydroxy-2,4,5- Trimethoxyisoflavone and 7-Hydroxy-4 -Methoxyisoflavone from Eysenhardtia polystachya

(2007) Estudio Etnobotánico de Eysenhardtia Polystachia (Ort.) Sarg. En una Comunidad del Municipio de Zempola, Hidalgo, y Evaluación del Efecto Diurético en Rata

(2007) Herbal Drugs in Urolithiasis - A Review

(2004) Effect of isoflavones from Eysenhardtia polystachya as inhibitors of calcium oxalate crystal aggregation

(2002) Effect of isoflavones isolated from heartwood of Eysenhardtia polystachya on the growth of oxalate crystals and urinary calcium phosphate 

(2006) Herbal medicine of the American Southwest: a guide to the medicinal and edible plants of the Southwestern United States