Learn about the Foods That Cause Kidney Stones

Kidney stones are a common health problem. It is marked by the build-up of small crystal-like stones in the kidneys. While several factors spur the formation of kidney stones, our food choices play a major role. Read through to learn about foods that cause kidney stones and how to prevent them with a healthy kidney diet. Let’s start with understanding all about kidney stones.

What are Kidney Stones?

Kidney stones are the accumulation of minerals and salts inside the kidneys. They have a stone-like appearance. While the smaller ones get eliminated from the body through urine, the ones bigger in size may block the ureters, thin tubes that carry urine from the kidneys to the bladder. This blockage can get extremely painful and will require immediate medical intervention. If left untreated, kidney stones can lead to repeated urinary infections and permanent kidney damage.

What Causes Kidney Stones?

Several reasons spur the formation of kidney stones. These are:

• Obesity or overweight
• Medical conditions
• Supplements
• Low fluid intake
• Certain medication
• Diet

Signs and Symptoms of Kidney Stones

Kidney stones will show no signs of presence until they begin to move around within the kidney or enter the ureter tube. 

Once the stone gets lodged in one of the ureter, the symptoms that surface include:

• Severe, sharp pain felt in the side and back just below the ribs
• Radiating pain that travels to the lower abdomen and groin region
• Pain with fluctuating intensity
• Pain while urinating
• Burning sensation while passing urine
• Pink, red or brown urine
• Foul-smelling urine
• Cloudy urine
• Persistent need to urinate. Inability to clear the bladder in one go
• Nausea and vomiting
• Fever and chills in case of infection

Types of Kidney Stones

Depending upon how they are formed, kidney stones can be of four types. These are:

1. Calcium Oxalate Stones 

It is the most common form of kidney stone. This is formed when calcium in the urine combines with too much oxalate, a naturally occurring chemical in foods. If you have been diagnosed with calcium oxalate stones, here’s the list of foods to avoid:

• Oxalate-Rich foods 

One should restrict foods rich in oxalates like spinach, almonds and/ or cashews, baked potatoes with skin, beets, cocoa powder, okra, French fries, raspberries, stevia sweetener, and sweet potatoes.

• Salt (Sodium)

Salt increases the level of calcium in the urine. So, limit your intake of salt.

• Animal Protein 

A high protein diet reduces the levels of urinary citrate. The presence of urinary citrate in the urine helps prevent the formation of kidney stones.

• Vitamin C

Although Vitamin C is a water-soluble vitamin and excess levels leave the body through urine, high amounts of Vitamin C in the body increase the production of oxalate which may lead to the formation of calcium oxalate stones in a susceptible person.

2. Calcium Phosphate Stones

To form calcium phosphate stones, the calcium in the urine combines with phosphorus. The foods to avoid with kidney stones are:

• Animal protein

A high protein diet reduces the levels of urinary citrate. The presence of urinary citrate in the urine helps prevent the formation of kidney stones.

• Salt (Sodium)

Salt increases the level of calcium in the urine. So limit your intake of salt.

• Alkaline foods

These foods make the urine more alkaline, leading to the formation of stones. These include fresh fruit and vegetable juices.

• Processed foods

Phosphorus is a commonly used preservative in processed foods. So limit the intake of processed foods.

3. Uric Acid Stones

Uric acid stones are formed if the urine is too acidic or if the levels of uric acid in the body are too high. Uric acid is produced upon the breakdown of food. Foods to avoid for kidney health are:

• Animal protein 

Too much of Animal protein is broken down to uric acid. Moreover, they reduce the levels of citrate, which naturally helps in preventing kidney stones. Instead of animal protein, a healthy kidney diet must include plant protein like beans, dried peas, lentils, peanuts, soy, almonds, nuts, etc.

• Sugary foods

Foods and drinks that contain a high amount of sugar, especially high-fructose corn syrup, can lead to the formation of kidney stones.

• Alcohol

Alcohol increases the levels of uric acid in the blood.  

4. Cystine Stones

These are the rarest kind of kidney stones. They are typically caused due to genetic conditions in which the natural substance called cystine leaks into the urine. The condition is called cystinuria. Cystine stones are bigger with repetitive formation. 

To restrict or limit the formation of such stones, consider the following:

• Drink adequate water as it will weaken the potency of cystine to form stones.
• Limit animal protein and switch to fresh fruits and vegetables.
• Cut down on sodium as it increases the level of calcium in the urine. 

Foods That Cause Kidney Stones and Other Conditions

The list below contains certain foods that cause kidney stones. Here is a list of foods that you must avoid for kidney stones. These include:

1. Dark-coloured sugary sodas – They contain phosphorus in their additive form, which is highly absorbable.
2. Processed and canned foods – They contain a high amount of sodium.
3. Processed meat – It contains high amounts of sodium and animal protein.
4. Pickles – Pickles contain a high amount of sodium.
5. Fast food – Fast foods like pizza, burgers and French fries contain a high amount of sodium.

Foods That Promote Kidney Health

Conscious changes made in the daily diet can go a long way in promoting kidney health. Healthier kidneys are less prone to kidney stones and other kidney disorders. Listed below are kidney healthy foods:

1. Red Bell Peppers – Are rich in antioxidants, vitamins and minerals.
2. Cabbage – Contains is rich in phytochemicals. It is also rich in vitamin K, vitamin C and fibre.
3. Cauliflower – Cauliflower is a low-potassium vegetable. It also contains good amounts of folate and Vitamin C.
4. Garlic – Garlic has great antimicrobial properties. It is low in potassium. Garlic powder is a great salt substitute.
5. Onions – Onions contain low amounts of potassium and are a rich source of chromium, a mineral important for the metabolism of carbohydrates, fat and protein.
6. Apples – Apples are high in fibre and have anti-inflammatory compounds.
7. Raspberries – Raspberries are low-potassium fruit. It contains ellagic acid, a phytonutrient that is a potent antioxidant.
8. Strawberries – Contain a low amount of phosphorus.
9. Cherries – Contains low amounts of phosphorus and exhibit anti-inflammatory properties.
10. Red grapes – Contain a low amount of phosphorus.
11. Egg white – Contains a low phosphorus amount and packs all essential amino acids.
12. Fish – Fish oils decrease urinary citrate and oxalate levels.
13. Olive oil – Contains the lowest amounts of sodium, potassium and phosphorus as compared to other oils.

Conclusion

Kidney stones are a build-up of hard minerals and salt in the kidney. They form crystal-like stones. The main causes include obesity, medical conditions, nutrient supplements, low fluid intake and diet. Lifestyle changes can thus go a long way in reducing the risk of kidney stones. First and foremost is avoiding foods that cause kidney stones. The types of foods to avoid will depend upon the type of kidney stone. There are four types of kidney stones – calcium oxalate stones, calcium phosphate stones, uric acid stones, and cystine stones. As the name suggests, each type of stone is caused by the accumulation of a particular mineral. Thus, a kidney healthy diet will be the one that restricts the intake of the particular mineral.