The prevalence of acid reflux and the increasing popularity of alkaline diets make people want to avoid acidic foods.

Acid-forming foods and foods with an acidic pH are quite different: the former are those that promote acidity in the body. On the other hand, not all foods with an acidic pH promote an acidic environment in the body.

Here we discuss the differences between foods with an acidic pH and acid-forming foods, as well as why and how to limit acidic foods.

Here we explain 6 acidic foods.

Acid-forming foods

Have you heard of alkaline diets? They are said to promote a non-acidic environment in the body by focusing on non-acidic fruits, vegetables, and other low acid foods.

Your body’s pH level of about 7.4, which is slightly alkaline or basic, is maintained through mechanisms like urination and breathing.

However, different body parts have different pH levels, e.g., your stomach’s pH level is very acidic (1.35–3.5) to break down the foods you eat.

Although the blood pH is tightly regulated, your urine pH changes depending on the need to balance the pH levels in your body, and is altered by what you consume.

Foods have different potential renal acid loads (PRALs), which are measured by the acid load excreted by the kidneys to maintain your body’s pH.

Dietary acid loads

Generally, foods that contain a high dietary acid load include processed grains, meat, soft drinks, and cheese, while those that have a low dietary acid load include fruits and vegetables—they tend to be basic or alkaline in nature.

Western diets tend to be low in fruits and vegetables and high in animal protein and other high-PRAL foods.

Plant-based diets rich in fruits and vegetables—diets that carry a low acid load—may help promote heart and kidney health. Diets with a high acid load, on the other hand, may have the opposite effect; they have also been associated with increased obesity rates, blood sugar levels, and levels of the inflammatory marker C-reactive protein (CRP).

Thus, limiting foods that have high PRALs and increasing foods with low PRALs, such as fruits and vegetables, is a good idea.

Here are some of the most popular foods that have high dietary acid loads.

Processed grains

Western diets typically involve consuming refined grain products, including white bread, baked goods, and fast food—foods that have a high dietary acid load.

To help reduce acid load, replacing refined grains with alkaline foods, such as fruits and vegetables, is a great idea.

Red meat and other animal proteins

Among the most prevalent acid-producing foods in the Western diet are red meat and other animal protein.

Packed with protein and phosphorus, red meat increases dietary acid load. Moreover, eggs, chicken, and other animal proteins also contribute to a high dietary acid load.

Soft drinks

Soft drinks contain significant amounts of phosphoric acid, which contribute to a high dietary acid load.

Notably, excess phosphorus has been linked to adverse health effects.

Moreover, soda intake has been associated with kidney issues, decreased bone mineral density, and prediabetes. This may be partly due to the acid load of soda.

Cheese and dairy products

Containing high phosphorus, dairy products like cheese, ice cream, and milk also contribute to a high dietary acid load.

Although they are nutritious, a dairy product-rich diet with low plant foods may also contribute to a high dietary acid load.

Dairy carries potentially acid-forming compounds, such as sulfur-containing amino acids, phosphorus, and chloride.

Foods with an acidic pH

Some foods, such as tomatoes and citrus fruits, have an acidic pH that don't form acid in the body—they have low PRALs.

These foods, however, can trigger symptoms of gastroesophageal reflux disease (GERD), which is a digestive disorder characterized by regurgitation and heartburn. Thus, people with GERD may need to avoid these foods.

Affecting ~ 20% of the US population, GERD is usually treated through medication and dietary changes.

Below are some of the foods that have an acidic pH.

Tomato-based products

Tomato-based products, such as tomato sauce and salsa, can cause reflux symptoms.

Thus, people with GERD are recommended by the National Institutes of Health (NIH) and American College of Gastroenterology (ACG) to avoid or reduce their intake of tomato products. But they may tolerate raw tomatoes better compared to processed tomato products. This may be due to the fact that cooked tomato products, including tomato sauce, tomato paste, and ketchup, are more acidic compared to fresh tomatoes.

It is important to note that tomatoes are a great source of lycopene. They are highly nutritious and a powerful antioxidant linked to numerous benefits.

That said, tomato products should not be avoided unless they exacerbate reflux symptoms.

Citrus fruits

Having an acidic pH, citrus fruits, including oranges, lemons, and limes, are known to exacerbate symptoms of GERD. They are considered reflexogenic, which means that they trigger or worsen reflux.

However, it is noteworthy that citrus fruits are packed with beneficial nutrients; what’s more, they are also associated with numerous health benefits. Thus, cutting citrus fruits from your diet may not be a good idea unless they worsen symptoms of reflux.

Should you totally cut these acidic foods from your diet?

Remember that foods with an acidic pH are different from those that contribute to a high dietary acid load.

Although foods like tomato paste, tomato sauce, lemons, and limes have an acidic pH, they have low PRALs; thus, they are considered alkaline.

Avoiding high-PRAL foods, such as animal proteins and soda, and consuming more low-PRAL foods, such as fruits and vegetables, will yield positive effects when it comes to disease reduction and overall health.

In addition, some research has linked high-PRAL diets to some adverse effects like kidney and heart disease.

However, it is important to note that these findings are based on dietary patterns that are very high in soda, processed foods, and red meat and very low in plant foods.

Although reducing your intake of acid-producing foods can be beneficial, foods like red meat, yogurt, and cheese can have a space in a healthy diet. What matters most are the quantity of these foods and your overall diet quality.

Avoiding foods with acidic pH may be beneficial to people with GERD; it may help reduce symptoms of reflux. Other foods that help acid reflux go away include vegetables, ginger, and healthy fats.

Nevertheless, it is always best to speak with your healthcare provider before making any changes to your diet.

Why limit acidic foods?

A diet rich in acidic foods can cause acidity in your urine. It may also lead to various negative health effects, including the formation of a type of kidney stone called uric acid stones. It may also cause bone and muscle deterioration.

Conclusion

Western diets may harm your health considering that they tend to involve foods that have a high dietary acid load.

Increasing your intake of fruits and vegetables and reducing your intake of soda, refined grains, red meat, and cheese may help reduce the acid load of your diet.

People with GERD may need to avoid foods with an acidic pH to lessen reflux symptoms. Many of these foods though are perfectly healthy for those who don’t have GERD.

If you want to control your acid reflux or lower your dietary acid load by cutting out acidic foods, speaking with your healthcare provider is a great idea.