Which foods are acidic?

Dear Reader,

Contrary to popular belief, acidity isn't an inherently harmful quality. In fact, digestive enzymes in the stomach require an acidic environment to properly function. Furthermore, there is no evidence indicating eating foods that are higher in acidity leads to increased acidity in the stomach, blood, or the body as a whole. That being said, some foods are naturally acidic, while others cause the body to form acid. There are a wide range of foods that have higher amounts of acid, such as citrus fruits and coffee, while foods such as meat and dairy can help the body release acid. Ready for more explanation and examples? Keep reading!

Let's start off with defining acidity — acidity is the level of acid in a substance and it is ranked using the pH scale. The pH scale is a quantitative measure that denotes the acidity or alkalinity of a liquid using a range from 0 to 14. A pH value less than 7.0 indicates acidity, while a PH value greater than 7.0 indicates an alkaline base. A 7.0 on the pH scale is a neutral measurement, meaning that a substance is neither acidic nor alkaline. Water, for example, has a neutral pH level.

Now, to connect this to your question about acidic foods — acidic foods fall in the acidic range of the pH scale (0.0 – 6.9) but they're distinctly different from acid-forming foods, which are foods that create an acidic environment during digestion. Acidic foods usually contain carbonic acids, citric acids, or phosphoric acids. Some common examples include:

• Fruits (especially citrus fruits such as lemons, limes, and grapefruit)
• Soft drinks such as sodas
• Sports drinks
• Coffee
• Tea
• Alcohol beverages

Acid-forming foods, on the other hand, don't necessarily have low pH levels, but they release amino acids when they're digested. Such common examples include:

• Meat (both fresh and processed) 
• Poultry
• Dairy
• Fish
• Eggs
• Grains such as cereals

Presently, there is no evidence indicating that acidic foods are harmful to the stomach. In fact, your stomach — which contains hydrochloric acid, a substance with a pH value between 0.1 and 1.0 — is likely much more acidic than the foods you may already eat. While evidence indicates the stomach remains unaffected by acidic substances, some foods may affect the kidneys if they have a high potential renal acid load (also known as PRAL). PRAL estimates the amount of acid that is produced when foods are digested; therefore, if a food has a high PRAL value, more acid is created in the body. In response, the kidneys work to balance the body’s overall pH level and maintain the appropriate acidity level. Although there are some diets that focus on the exclusion of high PRAL value foods to avoid acid production, there is ultimately no scientific consensus as to whether those who eliminate said foods have improved health outcomes. 

You mentioned that you can't eat acidic foods. Considering how many foods contain acid or produce acid, it may be helpful for you when thinking about your diet where this information came from. Is this something you discovered through your experiences with acidic food? Did your health care provider advise you to eliminate them? Did you hear about this from another source? Thinking about where you heard this information and for what reason you're cutting them out may be useful for you as you determine what foods best support your body. For most people, unless they have a condition or diagnosis that restricts certain foods or food groups, eating a balanced diet with a variety of foods, whether they're acidic or alkaline, can help ensure all of their nutrients, vitamins, and minerals are being met. If you're having trouble figuring out which foods that are acidic or acid-producing make sense or not for your eating patterns, you may find it helpful to meet with a registered dietitian to help you with more tailored dietary suggestions.

Wishing you well,