Have you ever gone on a Food With Oxalic Acid diet and had the most difficult time sticking to it? The reason why it is so difficult is because your diet is usually lacking in essential nutrients. For example, when you eliminate an entire food group like dairy products, you are at a high risk of deficiency in calcium, Vitamin A and Vitamin D. We all know how important these vitamins are to our body’s overall health.
Food With Oxalic Acid
High oxalate foods include:
Leafy greens like spinach contain many vitamins and minerals, but they’re also high in oxalates. A half-cup of cooked spinach contains 755 milligrams.
- Soy Products
Products made from soybeans are excellent sources of protein and other nutrients, especially for people on a plant-based diet. However, they are also high in oxalates. A three-ounce serving of firm tofu has 235 milligrams, while 1 cup of soy milk or yogurt can have up to 336 milligrams per serving.
Almonds are concentrated with a range of vitamins and minerals, yet, they are also high in oxalates. One ounce of almonds, or about 22 nuts, contains 122 milligrams of oxalates.
A medium baked potato has 97 milligrams of oxalates per serving. Much of this content is in the potato’s skin, which contains high levels of nutrients like fiber, vitamin C, and B vitamins.
Beets are an excellent source of nutrients like folate and manganese. Research shows their nitric oxide content helps lower your blood pressure. At 152 milligrams per cup, they’re also one of the vegetables highest in oxalates.
- Navy Beans
Legumes are a great way to add protein, fiber, and other nutrients to any meal. However, if you’re managing your oxalate levels, navy beans are on the high end with 76 milligrams per half-cup.
Many fruits contain some oxalates, like avocados, oranges, and grapefruit, but raspberries are considered a high-oxalate food with 48 milligrams per cup.
Dates are highly nutritious dried fruits often used as a sweetener in cooking and baking. Date consumption should be moderated, however, as they are high in sugar and concentrated with oxalates with one date containing 24 milligrams.
Why You Should Avoid Oxalates
Your body naturally gets rid of oxalates, but in high amounts, they can have adverse effects. However, since foods containing oxalates are often nutritious in other ways, you shouldn’t remove them from your diet altogether.
Most people get between 200 and 300 milligrams of oxalates daily. If you’re at risk for kidney stones, sources suggest consuming less than 100 milligrams a day. Doctors may also recommend “low-oxalate diets” of less than 50 milligrams daily for some people. Talk to your doctor about what diet is best for your health.
A diet high in oxalates may have some negative effects, including:
Increased Risk of Kidney Stones
Estimates show that 1 in 10 people are affected by kidney stones, though some people are at more risk than others. When oxalate levels are high, there’s a greater chance it will bind to calcium, forming kidney stones.
Lower Mineral Absorption
Because oxalates bind to minerals like calcium, they can prevent your body from absorbing beneficial nutrients in your digestive tract . Yet, they don’t block absorption completely, and our bodies only use a portion of the nutrients we consume.
Some of the oxalates you consume are broken down in your gut, reducing the amount that passes through your digestive and urinary systems. However, when you take antibiotics, this effect is reduced. Antibiotics decrease the good bacteria in our gut that absorb oxalates, which can enhance their activity.
Foods high in oxalate (oxalic acid) include spinach, firm tofu, soy milk, potatoes, beets, raspberries, navy beans, almonds, and dates
Oxalates, also called oxalic acid, is a concern for people with kidney disease or kidney stones. In high amounts, oxalates can bind with calcium as they are excreted from the body and thereby increase the risk of kidney stones.
If you are prone to kidney problems, your doctor may recommend a low-oxalate diet, which is 50 mg of oxalates per day.
Foods high in oxalates (oxalic acid) include:
- Spinach: 755 mg per ½ cup
- Firm tofu: 235 mg per 3-ounce serving
- Soy milk: 336 mg per 1 cup.
- Potatoes: 97 mg per serving
- Beets: 152 mg per 1 cup
- Raspberries: 48 mg per 1 cup
- Navy beans: 76 mg per ½ cup
- Almonds: 122 mg per 1 ounce
- Dates: 24 mg per 1 date
Other oxalate-rich foods include:
- Bran flakes
- French fries
- Nuts and nut butter
- Soy seeds
5 tips for preventing kidney stones
1. Drink plenty of water or other fluids daily
Aim to drink at least 10-12 glasses (or 2 liters) of fluids a day, making sure 5-6 glasses are water. This will help your body flush out oxalates from your system.
2. Increase your calcium intake
Not eating enough calcium can increase the risk of kidney stone formation. This is because calcium binds to oxalates and reduces the amount of oxalates that the body absorbs.
Aim to consume 800-1200 mg of calcium per day. This can be done by eating 2-3 servings of calcium-rich foods.
One strategy is to have meals that contain both high-calcium foods and high-oxalate foods, for example, low-fat cheese with a spinach salad or yogurt with berries. This is a good way to have your favorite oxalate-rich foods while avoiding any unhealthy effects.
3. Consume vitamin C in moderation
Vitamin C produces oxalate as an end product, so consuming too much vitamin C (more than 500 mg) may be bad for you if you are prone to developing kidney stones.
4. Boil oxalate-rich vegetables
Boiling vegetables can lower their oxalate levels by more than 50%, depending on the vegetable.
5. Switch to low-oxalate alternatives
You can switch to low-oxalate foods such as:
- Kale (alternative to spinach)
- Bok choy (alternative to spinach)
- Cashews (alternative to almonds)
- Peanuts (alternative to almonds)
- Walnuts (alternative to almonds)
- Pumpkin seeds (alternative to soy seeds)
- Sunflower seeds (alternative to soy seeds)
- Sweet potato (alternative to baked potato)
- Kidney beans (alternative to navy beans)
- Blueberries (alternative to raspberries)
- Blackberries (alternative to raspberries)
- Dried figs (alternative to dates)
What is oxalic acid (oxalate), and is it dangerous?
- What is it?
- Health risks
- How to avoid it
Many fruits, vegetables, nuts, and whole grains contain a naturally occurring compound called oxalic acid, which people sometimes refer to as oxalate. Although small amounts of oxalic acid are not harmful, this compound can inhibit the absorption of other important nutrients.
For this reason, some people refer to oxalic acid as an anti-nutrient. In some people, it can also increase the riskTrusted Source of kidney stones.
Certain gut bacteria can metabolize, or break down, oxalic acid. This prevents it from binding to minerals and affecting nutrient absorption.
This article looks at oxalic acid and its associated risks in more detail. It also lists dietary sources of the compound and explains how people can decrease their intake.
What is it?
Oxalic acid is a common organic compound. A range of living organisms — including fungi, bacteria, plants, animals, and humans — produce it.
Technically, oxalate occurs when the oxalic acid in plants binds to minerals. However, many people use the terms interchangeably.
The body can either produce oxalate as a waste product or obtain it from the diet.
Oxalate can combine with other minerals in the body to form compounds such as calcium oxalate and iron oxalate. People can then eliminateTrusted Source these oxalate compounds in the urine or stool.
However, some individuals with high oxalate levels may developTrusted Source kidney stones.
What is it used for?
Although oxalic acid naturally occurs in plants and humans, it also has a variety of uses in industry. These uses include:
- removing rust
- removing stains
- stripping and cleaning
- removing wax
- cleaning wood
- dyeing textiles
Laboratories may also use oxalic acid and oxalate salts as anticoagulants in blood specimens.
In small amounts, oxalate is harmless. However, higher levels may reduce the body’s mineral absorption and contribute to kidney stone formation.
People refer to oxalates as anti-nutrients. This is because they bind to certain minerals and prevent the body from absorbing and utilizing them.
One good example is spinach. Although it is rich in the important nutrients calcium and magnesium, it is also high in oxalate. The oxalate forms a complexTrusted Source with these minerals and can inhibit absorption.
The other concern with oxalate is that it can contribute to kidney stones.
Most people have a small amount of oxalate and calcium in the urinary tract at some point. Usually, they remain dissolved, and there are no associated problems.
However, in some people, the compounds form crystals and then kidney stones. ResearchTrusted Source has shown that this is a particular problem if oxalate levels are high and urinary volume is low.
There are several types of kidney stones, which comprise different minerals, but calcium oxalate is the most common. Therefore, if a person is prone to developing kidney stones, their doctor may advise them to reduce their intake of oxalate-rich foods. They should also consume enough calcium and avoid vitamin C supplements.
The gut and oxalate absorption
Certain bacteria in the digestive system can metabolize some dietary oxalate before it binds to minerals. This process can prevent oxalate’s potentially harmful effects.
A type of gut bacteria called Oxalobacter formigenes breaks down oxalate and uses it as energy. Having this bacteria in the gut microbiome significantly reduces the amount of oxalate in a person’s body.
Many people have O. formigenes in their gut. According to research, it is present in the feces of about 60–80% of adults.
Some people who experience recurrent calcium oxalate kidney stones have less of this bacteria.
Certain factors, such as taking antibiotics, can reduce the number of good bacteria in the gut. Additionally, people with altered gut function, such as those with inflammatory bowel disease (IBD), have an increased riskTrusted Source of developing kidney stones.
How people consume it
People typically consume oxalate through dietary sourcesTrusted Source. Almost all plants, including fruits and vegetables, contain oxalates, having the highest concentration in the leaves and seeds. However, the amount they contain varies considerably.
Vegetables that are particularly high in oxalate include:
- swiss chard
- sweet potatoes
- potato skins
Other dietary sources rich in oxalate include:
- black tea
- nuts, such as almonds, Brazil nuts, and pine nuts
The amount the body can absorb from foods depends on the quantity of soluble oxalates the foods contain and the bioavailability of these oxalates. For example, tea has a significantly higher rate of oxalate absorption than spinach or rhubarb.
The method of food preparation and cooking can also affect the oxalate content. Soaking certain vegetables and legumes can reduceTrusted Source the amount of oxalate they contain.
How to avoid it
The best way to avoid oxalate is to reduce the intake of oxalate-rich foods.
It is important to eat a variety of fruits and vegetables. However, if a person is concerned about the number of oxalates in certain foods, they can replace them with low oxalate alternatives. Some examples include:
|High oxalate food||Low oxalate alternative|
|black tea||fruit tea|
|dark chocolate||white chocolate|
Boiling vegetables also reduces their oxalate content. Research shows that boiling could remove up to 76%Trusted Source of oxalates, depending on the vegetable.
It is also important to eat enough dietary calcium. This mineral can bind to oxalate in the digestive system and reduce how much the body absorbs. Therefore, eating milk, yogurt, or cheese alongside foods containing oxalates can reduce the likelihood of developing issues such as kidney stones.
Oxalate is a compound present in many plant-based foods, including spinach, chard, and kale.
In the digestive system, oxalate can form complexes with minerals such as calcium and interfere with their absorption. Additionally, a high oxalate diet may lead to some people developing kidney stones.
Doctors may advise some individuals to consume a low oxalate diet. They can do this by replacing high oxalate foods with low oxalate alternatives, boiling vegetables, and eating foods rich in calcium alongside high oxalate foods.
What Are The Oxalic Acid Uses In Food
The oxalic acid uses in food ranges from a preservative to a leavening agent in the field of baking. Food manufacturers use oxalic acid to stop the growth of bacteria in many foods. There is oxalic acid used in food such as cheese, baked goods, chocolates, and confectioneries. The oxalic acid usage in making chocolate protects the cocoa butter from turning rancid. It also acts as a bleaching agent for baking powder to give doughs a lighter crumb texture while it helps dough retain moisture during baking to control shrinkage.
Many industries also use oxalic acid because oxalates are much cheaper than fertilizers to manufacture.
Plants readily absorb formaldehyde oxalate, which decomposes to oxalic acid, carbon dioxide, and hydrogen peroxide under the influence of sunlight. This makes oxalic acid one of the most widely used preservatives due to the many oxalic acids used in food.
Everyday use of oxalic acid, among other things, is in the making of biodiesel fuel which can be used to modern power automobiles. Oxalic acid can also serve as bleach for paper pulp. Adding oxalic acid to milk causes it to curdle. Its calcium ions bind with hydrogen carbonate ions by precipitating them into chalky lumps as they do in hard water when adding ordinary baking soda. Oxalic acid is also used to produce plastics. Although oxalic acid has a sharp taste, it can be found in some fruit, including blackberries and raspberries, and coffee and chocolate.
The oxalates found in buckwheat flour react with water to form a gummy substance that inhibits the yeast activity during bread making. This makes sourdough bread making difficult as oxalates inhibit lactic bacteria growth during the long fermentation process of rye doughs standard for this kind of bread.
Oxalic acid is found naturally in many plants.
The oxalate compounds of calcium oxalate are water-soluble and contribute to the sharp taste of rhubarb stalks and leaves, an effect that is especially noticeable when these foods are cooked. Oxalic acid is usually found as oxalate salts such as sodium oxalate, potassium oxalate, calcium oxalate, and ammonium oxaloacetate. Since oxalates are extensively used in many industrial applications, oxalic acid production is increasing.
Spearmint gum flavorings can be formulated with oxalic acid due to their ability to kill certain microorganisms that cause spoilage after the chewing gum has been manufactured. Oxalic acid or ammonium oxaloacetate may also be present in certain processed foods as a leavening agent.
When plants are exposed to oxalates or oxalic acids, they produce organic acids that retard the effects of high soil pH caused by essential fertilizers such as ammonium nitrate, calcium nitrate, and potassium sulfate. These chemicals can damage plant roots if too much is absorbed within the soil.
However, oxalic acid is not typically used to decrease bitterness or increase sweetness in food manufacturing.
Oxalic acid is also a chemical irritant that can cause injury when taken internally or exposed to open wounds. The oxalic acid used in the food industry is considered safe because oxalates are only present at low concentrations in foods and do not affect flavor.
Oxalic acid should only be used by adults who understand its oxalate content, toxicity levels, and other oxalic acid uses in food. Parents should not leave oxalates within striking distance of children since it may irritate their eyes, skin, or digestive system if consumed accidentally.
Oxalic acid is a chemical compound with many uses in food, like oxalic acid salt, oxalic acid crystals, and oxalic acid powder. Oxalic acid was first isolated by forming salts with metals such as calcium oxides or potassium oxides. Commercially available oxalates are usually sold as solutions dissolved in water along with variable concentrations of oxalic acid.
Oxalic acid is a relatively safe and inexpensive organic compound with many uses in the food industry. Oxalic acid can be used as an antifungal agent, antioxidant, bleaching agent, and more. Oxalic acid may also be purchased through some chemical distributors.
Oxalic acid uses in food is available online in various quantities, depending on your needs. In oxalic acid’s primary uses as a food additive, it is most often encountered as its sodium salt, the conjugate base of oxalic acid. It can be used as a preservative for pear and grape juice. Furthermore, oxalic acid has been demonstrated to bind with six primary berry polyphenols: chlorogenic acid, ellagic acid, gallic acid, myricetin, quercetin, and kaempferol. The resulting oxalates are easily separated from the bound polyphenols via centrifugation of the plant extract. Therefore, Oxalic acid has been used safely by the food industry for many years