Which Food Is Acidic ? While acidic foods are famous for their tangy taste, some people start to feel uncomfortable after too much of an acidic diet. There are two major types of acids: weak and strong. The difference is how much effect they have on the body. This article will help you understand which food is acidic by revealing the effect of acidic food on your health.
What is acidity?
The pH value tells you whether something is an acid, a base, or neutral.
- A pH of 0 indicates a high level of acidity.
- A pH of 7 is neutral.
- A pH of 14 is the most basic, or alkaline.
The distance between two points on the pH scale represents a tenfold difference in the acidity or alkalinity of a substance. A pH of 6 is ten times more acidic than a pH of 7, and so on.
For example, battery acid is extremely acidic at 0, while liquid drain cleaner is very alkaline at 14. Pure distilled water is in the middle at 7. It’s neither acidic nor alkaline.
Just like different substances, different parts of the human body have different pH levels.
Your ideal blood pH is between 7.35 and 7.45, which is slightly alkaline. The stomach is typically acidic at a pH of 3.5, which helps to break down food properly.
Measuring acidity and alkalinity
Measuring the pH values of foods and drinks is how people determine the acidity or alkalinity of them.
The pH values can range from 0 to 14 with distilled water having a pH of 7, or neutral. Other types of water with impurities or minerals may have a slightly different pH value.
Anything below pH7 is acidic while anything above ph7 is alkaline.
pH levels in the body
Different parts of the human body have different pH levels. Within the digestive system, pH values range from extremely acidic to slightly alkaline.
Differences in pH levels within the different organs and body fluids allow them to fulfill their particular function:
| Body part/fluid | Role | pH level |
| Saliva | Eases passage of food through the food pipe and breaks down starch. | 6.5–7.5 |
| Upper stomach | Begins the predigestion process. | 4.0–6.5 |
| Lower stomach | Releases hydrochloric acid to break down food and kill bacteria. | 1.5–3.5 |
| Small intestine | Completes digestion and absorbs nutrients into the bloodstream. | 6.0–7.4 |
| Large intestine | Absorbs water and eliminates undigested food and fiber. | 5.0–8.0 |
Human blood should be slightly alkaline with a pH ranging from 7.35 – 7.45
A pH level in the blood that exceeds these limits in either direction will drastically impair metabolic processes inside the body.
The acid-ash hypothesis
The acid-ash hypothesis suggests that excessively acidic diets are bad for overall health.
Researchers based the hypothesis on the premise that foods that have been metabolized by the body leave behind a chemical residue known as ‘ash.’
When combined with body fluids, this ‘ash’ can be either acid-forming or alkali-forming, which could cause a reaction in the body.
According to the hypothesis, foods containing acid-forming substances lower the pH level of the blood, causing an accumulation of acid.
The body then compensates for this loss by leaching alkaline minerals, specifically calcium, from the bones and excreting them in the urine.
Supporters of the acid-ash hypothesis claim that regular and prolonged consumption of acid-forming foods increases mineral bone loss, thereby increasing the risk of conditions, such as osteoporosis.
Foods containing acid-forming substances include:
- meat
- grains
- dairy
- unsprouted beans
- sunflower and pumpkin seeds
- nuts
- carbonated drinks
- alcohol
- coffee and other caffeinated drinks
- sweeteners
- refined table salt
- tobacco
Foods that promote alkalinity, or ‘base-forming’ foods, are thought to prevent or counteract the effects of excess acid in the body. These foods include most fruits and vegetables.
Even citrus fruits, which are initially acidic, promote alkalinity once metabolized.
Proponents of the acid-ash hypothesis encourage regular pH testing of the urine as a means of monitoring the pH level of the body.
This information is then used to inform a person’s dietary choices.
What does the evidence say?
Knowledge of human physiology and evidence from clinical trials are both helpful in understanding the effects of acidic foods on blood pH and overall health.
Acid-base homeostasis
Supporters of the acid-ash hypothesis claim that diet affects blood pH level.
However, the body’s buffering system tightly regulates blood pH in a process known as acid-base homeostasis.
Examples of buffers include calcium stored in bone, proteins, or other mechanisms by which the body resists pH changes in the bloodstream.
The following two mechanisms are primarily involved in this process:
- Respiratory compensation: Breathing rate increases when acid levels are high. This breaks down the carbonic acid in the blood to water and carbon dioxide or CO2. The process, including the exhalation of the CO2, returns blood pH to normal levels.
- Renal compensation: The kidneys produce bicarbonate ions, which neutralize acid within the blood.
These two mechanisms are so effective at balancing acids and bases that it is almost impossible for a person’s diet to have any influence on blood pH.
A blood pH level that falls below pH 7.35 indicates a severe problem with lung or kidney function.
This condition, termed acidosis, causes a buildup of acid in the tissues and fluids and can be fatal if left untreated.
Low Acid Foods
Bananas
“Bananas are generally considered to be alkaline in nature and not acidic,” says Patrick Takahashi, MD, a gastroenterologist at St. Vincent Medical Center in Los Angeles. “They are a good source of fiber and vitamin B6, and help with maintaining potassium, which is good for your heart and bones in general.” Raw bananas are probably the best source of nutrients. You can eat them at any time, for a snack or with a meal. In some low-acid baking recipes, you can mash them up as a substitute for a fat component.
Skinless Chicken
Skinless chicken makes a great low-acid diet staple. High in protein, a 4-ounce portion provides two-thirds of the recommended daily amount. While chicken is perfectly fine, deep-frying it in greasy oil will only trigger heartburn. Prepare it mindfully, with as few reflux-triggering spices as possible.
Apples
Another low-acid option, apples make a great source of fiber, too. “Fiber can help you stay full longer, which can minimize overeating during the day,” says Tara Harwood, MS, RD, a dietitian at the Cleveland Clinic’s Digestive Disease Institute. “Fiber also helps with lowering cholesterol and preventing spikes in blood sugar.” Even the skins, which have polyphenols and flavonoids, can be good for you.
Fish
Fish is a nutritious component in any diet but an excellent source of protein in a low-acid diet. Salmon, for example, contains omega-3 fatty acids, which benefit the heart, joints, and eyes. It may also protect against certain kinds of cancer. As with chicken, the most effective GERD recipes for fish will limit or exclude spices and heavy seasonings to avoid heartburn issues. And remember to skip the lemon. Its low pH makes it acidic.
Oatmeal
Oatmeal is a great breakfast option for people sticking to a low-acid diet. High in filling fiber, oats can help improve cardiovascular health and stabilize blood sugar, among other benefits. When topping off a hot bowl of oatmeal with fruit, remember to avoid ones high in acid, like strawberries, blueberries, and cranberries.
Almonds
Unlike other nuts such as pecans, cashews, and walnuts, almonds are generally alkaline. The monounsaturated fatty acids and omega-3 fatty acids almonds contain can protect the heart and the high fiber content can keep you feeling full between meals. Almonds also contain Vitamin E, a natural antioxidant, and the minerals manganese and magnesium. Use almonds in place of other nuts when preparing low-acid recipes.
Fruits high in acid
Although most types of fruit are acidic, they’re considered alkalizing, meaning that they actually help reduce acid levels in the body .
This also means that they have a negative PRAL, which is a value used to estimate the amount of acid produced during digestion for certain foods.
Here is the PRAL for a 3.5-ounce (100-gram) portion of several popular fruits
- limes: -0.4
- plums: -1.7
- green grapes: -2.4
- purple grapes: -1.9
- pomegranates: -8.1
- blueberries: -0.6
- pineapples: -1.1
- apples: -1.8
- peaches: -1.5
- oranges: -1.6
- tomatoes: -1.8
- raisins: -9.0
- blackberry: -1.0
- banana: -5.2
Keep in mind that although these fruits are alkalizing in the body, their initial acidity could worsen symptoms for those with upper gastrointestinal issues like an ulcer or reflux.
In fact, those with conditions like gastroesophageal reflux disease (GERD) are often advised to limit their intake of acidic foods, including citrus fruits like oranges, grapefruit, lemons, and limes.
Fresh vegetables
Like fruits, vegetables are also considered alkalizing and can help reduce acid levels in the body.
Here is the PRAL for a 3.5-ounce (100-gram) serving of some common vegetables:
- white cabbage (raw): -1.5
- beets (raw): -5.4
- shiitake mushrooms (cooked): -0.2
- kale (raw): -2.6
- zucchini (cooked): -0.6
- spinach (raw): -1.5
- cucumber (raw): -2.0
- potato (cooked): -1.7
- radish (raw): -4.7
- pumpkin (cooked): -1.9
- arugula (raw): -1.1
- artichoke (cooked): -0.5
Drinks high in acid
You may choose to avoid high-phosphorus drinks such as beer or hot chocolate made from packets of cocoa mix. If you do wish to drink alcohol, go with lower-phosphorus red or white wine.
Carbonic acid, which is present in all carbonated beverages, including not only soft drinks but sparkling waters and spritzers, contributes to your total body acid.
If you want to lower your acidity, regular or filtered tap water is best.
What Happens When You Eat Acidic Foods?
Everything that you eat has to come in contact with the gastric juice in your stomach. This gastric juice is highly acidic and has a pH between 1.5 to 3.5 (equivalent to hydrochloric acid).
Our body has mechanisms to strictly control the pH in the gut and levels of gastric juice in the stomach. When the pH of your stomach is already acidic, and you eat acidic foods, a cumulative effect is created that lowers the pH in your gut even more.
It’s like adding fuel to the fire!
There’s too much acid generated at once, which can give rise to conditions like:
1. Gastroesophageal Reflux Disease (GERD)
Consuming highly acidic foods can damage the protective inner lining of your stomach, giving you dreadful ulcers and terrible acid reflux.
What’s worse is if this acid reflux and inflammation continue and reach the upper GI tract and esophagus, which do not have a protective mucus-secreting cell lining (like your stomach). It can lead to chronic burning sensation, dyspepsia, acidity, heartburn, and ulcers in your mouth.
This is what happens when you have GERD. Trust me, you will not be able to swallow something as soothing as cold milk!
2. Causes Tooth Decay
Eating or drinking sugary and starchy foods can lead to the formation of a thin, sticky, invisible film of bacteria called plaque all over your teeth.
When high sugar foods come in contact with plaque, the acids that digest the food attack your teeth till almost 20 minutes after you finish eating.
Repeated acid attacks like these break down the hard enamel layer on your teeth, ultimately leading to tooth decay. Something similar happens in the case of acid reflux too.
3. Can Give Rise To Bone Diseases
Due to the Western diets that have a high acid, sodium, and bicarbonate content, and low potassium and calcium content, there is a gradual loss of bone density.
The urinary loss of calcium (which increases by 74% when on highly acidic foods), an inadequacy of potassium and vitamin D, and hypertension together trigger bone resorption and early onset of bone diseases like osteoporosis.
4. Could Cause Kidney Stones
The excretion of minerals like calcium, potassium, and magnesium through urine is essential for your kidneys’ health.
Having highly acidic foods can cause your kidneys to retain a fraction of these minerals while generating urine.
Over time, such mineral deposits turn into renal calculi or kidney stones. These could be fatal if left untreated.