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Oxalate in Grapes: Vines & Vitals

man holding a bunch of grapes

Grapes are small, juicy fruits with flavours ranging from sweet to tart. Many people love grapes. You can eat grapes fresh, dried as raisins, or make them into wine. Grapes contain a less-known component called oxalate. Oxalate is worth paying attention to.

What is Oxalate?

Oxalate, or oxalic acid, is a natural compound in plants, vegetables, and fruits like grapes. It can combine with minerals like calcium to form calcium oxalate, a common type of kidney stone. This helps create kidney stones.

Oxalate in Grapes

Grapes have a low oxalate content. Oxalate is in grapes to protect the plant. It's in different amounts in various grapes and grape products like wine and raisins. Grapes have less oxalate than some other foods. People sensitive to oxalate or getting kidney stones should watch how much they eat. Sources vary be sure to check.

Table Comparing Oxalte in Graps to Similar Fruit

Please research and speak to a medical professional before making dietary changes. I have listed the sources I use in the Resource Library. I am not a medical practitioner, just someone trying to raise awareness.

Here is a comparison table based on the OHF database.


Average Ox (mg) per 100 g

Serving Size

Serving Size (g)

Calc Oxalate per serving

Oxalate level

Blackberries, fresh


1 cup




Blueberries, fresh or frozen


1 cup




Grapes, dried, red or green, raisins


1/4 cup




Grapes, Green or Red


1 cup




Raspberries, raw


1 cup




Strawberries, fresh


1 cup, halves




Health Implications

Most people can eat grapes without worrying about oxalate health risks. The body can usually process the oxalate in grapes. But if you've had kidney stones from oxalate before, watch how many grapes you eat. Talk to a doctor for personalized diet advice.

Nutritional Benefits vs. Oxalate Content

Grapes are healthy because they have antioxidants, vitamins, and minerals. They can help your heart, decrease inflammation, and lower disease risk. If you're thinking about eating grapes, consider the oxalate they contain. This is important if you're prone to kidney stones.

Managing Oxalate Intake

If you need to manage your oxalate intake, here are a few tips:

  • Enjoy grapes in moderation, especially if oxalates bother you.

  • Drink plenty of water to prevent kidney stones by diluting oxalate in urine.

  • Eat a mix of fruits and veggies to avoid getting too much oxalate from one food.

  • Talk to a doctor or dietitian. They can give you personalized advice on oxalate and kidney stones.

Kidney Stones

Kidney stones are hard lumps that form in your kidneys from tiny crystals. There are different types of kidney stones. One common type is made from calcium and a substance called oxalate. Calcium oxalate stones can form when there’s too much oxalate in your urine, especially if you eat a lot of foods with high oxalate levels. Having knowledge about oxalates can help you to avoid the formation of kidney stones.

Some foods have a lot of oxalates. For example, swiss chard, and beetroot juice can increase the risk of kidney stones if you eat them often. Some people may have a higher risk for kidney stones genetically. The formation of kidney stones is avoidable if diet is the main cause.

Your Diet and Kidney Stones

What you eat can affect your chances of getting kidney stones. Eating animal products can lead to the formation of kidney stones. Eating too many high-oxalate foods can make it more likely for stones to form. To prevent this, balance these foods with plant-based calcium-rich options.

Calcium helps bind oxalates in your stomach so they don’t get to your kidneys.

Try not to eat animal protein, salty foods, or processed foods. These can make your body release more calcium, which can lead to stones. Instead, eat a mix of plant-based foods, low-oxalate foods, and moderate amounts of protein to keep your kidneys healthy.

Low-Oxalate Diet

A low-oxalate diet can help reduce your risk by encouraging you to eat fewer foods with high oxalates. Instead, you choose foods that are low in oxalates. People who are likely to get kidney stones should eat low-oxalate foods to stay healthy. Variety is important in your diet but you will need to limit foods high in oxalate. Pair them with lower oxalate foods.

High-Oxalate Foods to Avoid

Some foods are very high in oxalates and can cause kidney stones. These include nuts, some dark leafy greens like spinach and Swiss chard, and dark chocolate. If you need to eat fewer oxalates, look for alternatives.

Low-Oxalate Choices: You can still enjoy a variety of foods by choosing low-oxalate options like tomato juice, wheat bread, and vegetable soup. These help you manage your oxalate intake and reduce the risk of kidney stones.

Why Fluids Are Important

Drinking plenty of water is one of the best ways to prevent kidney stones. Fluids help flush out the minerals and salts that can form stones. Hydration is crucial to avoiding the formation of kidney stones.

Aim to drink five to eight glasses of water each day (at least). Staying well-hydrated makes it harder for kidney stones to form. Water and lemon water are good choices to keep your kidneys healthy. Another idea is to eat low oxalate fruits with a high water content.

Keeping Your Kidneys Healthy

Healthy Habits To keep your kidneys healthy and avoid kidney stones, watch your diet and drink plenty of fluids. Avoid too much caffeine, salty snacks, and fatty foods. Also, keep an eye on your urine; if it’s dark or you have pain, see a doctor early.

Regular Check-Ups: If you have had kidney stones before or have other kidney issues, talk to your doctor regularly. They can help you find the best diet and fluid plan to support your kidneys and prevent more stones.

By knowing which foods to eat and how much to drink, you can make choices that keep your kidneys healthy for the long term.


Grapes are tasty and healthy. Like some foods, they have oxalate. People prone to kidney stones should watch their oxalate intake. Eating grapes in moderation and having a balanced diet can help. To find out more about oxalate in greens, read Arugula Oxalates Rocket. Thank you for reading.


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