Kidney stones, known scientifically as nephrolithiasis, are a common and often painful condition that affects millions worldwide.

These solid mineral and salt deposits form in the kidneys and can vary in size, ranging from a grain of sand to a larger, more obstructive stone.

While the symptoms of kidney stones, such as severe flank pain and blood in the urine, are well-documented, their potential impact on weight is less frequently discussed.

This blog by Mykare Health delves into whether kidney stones can lead to weight loss and explores the associated medical, lifestyle, and psychological factors.

Understanding Kidney Stones

To understand the relationship between kidney stones and weight loss, it’s essential to grasp how kidney stones form and their typical symptoms.

Formation of Kidney Stones

Kidney stones develop when the concentration of certain substances, such as calcium, oxalate, or uric acid, becomes too high in the urine. This can lead to crystallization and the formation of stones. Factors like dehydration, diet, obesity, and certain medical conditions increase the risk of stone formation.

Symptoms of Kidney Stones

• Severe pain in the side and back

• Nausea and vomiting

• Difficulty urinating or painful urination

• Blood in the urine

• Persistent urge to urinate

These symptoms can disrupt daily life and impact overall health.

Weight Loss and Kidney Stones

Direct Link Between Kidney Stones and Weight Loss

Kidney stones themselves do not directly cause weight loss. However, the symptoms and complications associated with kidney stones can lead to indirect weight loss due to

• Reduced Appetite: The intense pain and nausea caused by kidney stones can suppress appetite. When individuals eat less, they may experience unintentional weight loss.

• Nausea and Vomiting: These common symptoms can lead to reduced food intake and dehydration, further contributing to weight changes.

• Lifestyle Changes: In severe cases, individuals may change their diet to manage or prevent kidney stones. These changes, such as adopting a low-sodium or low-protein diet, may inadvertently result in weight loss.

Indirect Factors Leading to Weight Loss

1. Pain and Discomfort

Severe pain caused by kidney stones can affect physical activity and appetite. Persistent discomfort may lead to emotional stress, which can contribute to unintentional weight loss.

2. Dehydration

Kidney stones are often linked to dehydration, a significant risk factor for their formation. Dehydration can cause fatigue, reducing the likelihood of maintaining a normal eating pattern, indirectly leading to weight loss.

3. Dietary Modifications

After a diagnosis of kidney stones, individuals are often advised to follow a specific diet to prevent recurrence. These diets might include

• Low Oxalate Diet: Avoiding foods rich in oxalates, like spinach, nuts, and chocolate.

• Low Sodium Diet: Excess salt increases calcium in the urine, promoting stone formation.

• Increased Fluid Intake: Drinking more water can dilute substances in the urine.

Although these changes are health-focused, they might lead to unintentional caloric deficits, causing weight loss.

4. Infection or Sepsis

If a kidney stone causes a urinary tract infection (UTI) or leads to sepsis, the body’s energy demands increase, and individuals may lose weight due to illness.

Can Weight Loss Increase Kidney Stone Risk?

Interestingly, there’s a bidirectional relationship between kidney stones and weight. Sudden weight loss, especially from extreme diets or bariatric surgery, can increase the risk of developing kidney stones. This happens because

• Rapid weight loss can lead to higher levels of oxalate in the urine.

• A high-protein, low-carb diet often used for weight loss increases acid in the urine, raising the risk of uric acid stones.

Managing Weight and Kidney Stones

To maintain a healthy weight without exacerbating kidney stone risks

1. Focus on Hydration

Drinking sufficient water is critical. Aim for at least 2-3 liters per day unless otherwise advised by a healthcare provider.

2. Balanced Diet:

Incorporate fruits, vegetables, whole grains, and lean proteins while avoiding high-oxalate or high-sodium foods.

3. Moderate Weight Loss:

Gradual and sustainable weight loss is healthier and less likely to increase the risk of kidney stones than rapid dieting.

4. Consult a Dietitian:

A registered dietitian can provide a personalized meal plan that promotes weight management while reducing the risk of kidney stone recurrence.

When to Seek Medical Attention

1. Severe Pain That Doesn’t Subside

Kidney stone pain, also called renal colic, is often described as one of the most intense types of pain. It typically starts in the side or back and can radiate to the abdomen or groin. If over-the-counter pain relievers don’t provide relief, it’s essential to seek medical care. Persistent or worsening pain could indicate a stone obstructing the urinary tract, which may require intervention.

2. Blood in the Urine (Hematuria)

Blood in the urine is a common symptom of kidney stones but can also signal infections or damage to the urinary tract. If hematuria is noticeable either red, pink, or brown urine or confirmed through lab tests, consult a healthcare provider immediately.

3. Persistent Nausea or Vomiting

Kidney stones can irritate the kidneys and urinary tract, triggering nausea and vomiting. If these symptoms prevent you from eating or staying hydrated, they can lead to rapid weight loss and dehydration, necessitating medical intervention.

4. Signs of a Urinary Tract Infection (UTI)

Kidney stones can obstruct urine flow, increasing the risk of UTIs. Seek immediate medical attention if you notice

• Burning sensation during urination

• Frequent urge to urinate with little output

• Cloudy or foul-smelling urine

• Fever or chills

Left untreated, a UTI can progress to a kidney infection (pyelonephritis) or sepsis, both of which are medical emergencies.

5. High Fever or Chill

A high fever, typically above 101°F (38.5°C), is not a common symptom of kidney stones but could indicate a severe infection or abscess. Fever alongside kidney stone symptoms should prompt an emergency room visit.

6. Difficulty Passing Urine

In some cases, kidney stones may cause partial or complete obstruction of the urinary tract. If you experience difficulty urinating, a weak urine stream, or feel like your bladder isn’t emptying, seek immediate care. A complete blockage is a medical emergency requiring prompt treatment.