I was recently given some advice by a friend to try a diet that is high in alkaline foods and low in acidic ones. Going without a bit of chilli to spice up my meals is one thing I can’t do, so I had to know if I would be able to continue to enjoy chilli peppers and stick to the diet.

Are chillies acidic or alkaline? Chillies are acidic. Green chillies are the least acidic with a ph of 5.20 – 5.93. Red chillies are more acidic with a ph of 4.65 – 5.45. Chilli sauces and condiments are the most acidic because they often contain vinegar or have been fermented which produces lactic acid.

At the outset it looked like I wasn’t going to be able to enjoy chillies if I went on an alkaline diet. Does chilli being acidic outweigh its other health benefits and would it be possible to enjoy chilli in a way that that doesn’t negatively affect the alkaline diet?


Why are Chillies Acidic

Chillies contain high levels of vitamin C, up to seven times higher than that of oranges. Vitamin C is also known as ascorbic acid. The high levels of vitamin C in chillies quite likely account for some of their acidity, even though ascorbic acid is a weak acid.

Green chillies contain the highest amount of vitamin C, about 240 mg per 100gr. Where red chillies only contain around 140 mg per 100gr. This shows that the vitamin C in chillies is not the only contributor to their acidity.

The main contributor to the acidity of chilli peppers is most likely their high antioxidant content. While it is commonly known that antioxidants are good for us, it is less commonly known antioxidants are acidic. This isn’t something to be concerned about however; antioxidants still have great health benefits.

Antioxidants are a group of compounds commonly found in fresh fruit and vegetables. They counteract the harmful effects of free radicals in the body. Free radicals increase most due to poor diet and exposure to UV light.


How are the Acidic Compounds in Chilli Peppers Processed by the Body

Chillies, like many citrus fruit, are actually alkaline forming foods once we have digested them. After our bodies process and break down the acids in citrus fruit and chillies, the end product is alkaline.

The alkalizing effects of fresh chillies and citrus fruit in fact compliments the alkaline diet. Good news for those like me, who enjoy their chillies, but are interested in giving the alkaline diet a try.


Is the Colour of Chillies Affected by their Acidity

There are numerous compounds that give chillies their wonderful variety of colors, the most common ones being anthocyanin and carotene.

Anthocyanin is a molecule commonly responsible for the red color of many chilli varieties. Carotene belongs to the carotenoid group of compounds, responsible for yellow and orange colors in many fruit and vegetable, including chillies.

The fascinating thing about Anthocyanin is that it changes color depending on the alkalinity or acidity of the cell it’s in. In an acidic cell Anthocyanin turns red, in an alkaline cell it goes a blueish-purple color.

This is why some chillies are able capable of displaying purple or bluish tinge. This is not commonly observed, although if you have grown a few different chilli varieties you may have noticed it yourself.

Example of purple blushing on green chilli pepper - Photo by Chilli Source


Is Capsaicin Acidic or Alkaline

Many people are of the impression that the fiery sensation that we get from eating chillies is due to their acidity. This is actually not the case. Chillies contain a compound called capsaicin. Capsaicin is responsible for the warm to hot sensation that we experience when eating chillies.

Measured as an isolated compound, capsaicin is actually alkaline. It reacts with receptors on our tongues and skin responsible for sensing high temperatures and abrasions. There is no physical burning or damage that occurs.

After the initial pain or discomfort that capsaicin causes it is actually effective at relieving pain. For this reason it is commonly used in creams and topical ointments to relieve conditions from muscle and joint pain to rashes.

When consumed, capsaicin has been shown to inhibit the secretion of acid in the stomach and improves blood flow within the lining of the stomach.

It is commonly thought that eating chillies can cause stomach ulcers, but the effects of reducing stomach acid and improving blood flow actually contribute to the healing and prevention of stomach ulcers.


Chilli Sauce Acidity

Many chilli sauces are either fermented or contain vinegar and in general this makes them far more acidic than fresh chillies. Generally chilli sauces have a pH of 4.5 or lower.

Vinegar contains about 5 to 20 percent acetic acid; the rest is made up of water and flavourings. When vinegar is added to a sauce it lowers the pH dramatically, making the sauce more acidic.

Although vinegar is considered a weak acid, it is not alkalizing when metabolised by the body, it remains acidic.

The process of fermenting chillies or other foods like cabbage (to make kimchi or sauerkraut) produces lactic acid. Lactic acid has a pH value of around 2.4 which is relatively acidic. Like vinegar, when lactic acid is processed by the body it also has an acidifying effect.

Due to the acidifying effects of vinegar and lactic acid you may choose to exclude chilli sauces or consume them in moderation when following an alkaline diet.

Thankfully for many, hot sauce is easily used in moderation, but if you are looking for the healthiest alternative, fresh chillies are the way to go.


Why are Acidic Ingredients used in Chilli Sauces

Before the invention of refrigeration systems humans had to find ways to preserve food for long periods of time. There were no fridges or freezers, so we found other ways to keep food from going off. We discovered that by acidifying foods, or adding acids to foods, they could be preserved.

Many types of bacteria that have the potential to make us sick are not able to survive in acidic environments. We might not have know this at first, but we did learn from first hand experience that these foods lasted much longer than non-preserved foods and had less potential to make us sick.

One of the earliest methods discovered for acidifying food was through lactic acid fermentation. This type of fermentation produces lactic acid and only occurs in environments that do not contain oxygen, also known as anaerobic environments. Lactobacillus, a relatively common bacteria, must be present to produce the preserving lactic acid.

Many commonly consumed foods around the world are created through this fermentation process. Examples being: yogurt, sauerkraut, kimchi and many chilli sauces.

In more recent times, once the preserving effects of acids were well understood, we began to use other acids to preserve foods.

To preserve chilli sauce, vinegar, which contains acetic acid, is commonly used. The preserving effects of acids are why many chilli sauces can be stored outside of the refrigerator and maintain a long shelf life.

One of the other reasons that we add acids to chilli sauces is for flavour. Tangy or sour notes add that extra element of complexity to a hot sauce that many people find really appealing. A good example of this is Tabasco sauce which has a high vinegar content and has been a popular hot sauce for many years.

If you are looking for a way to add some tanginess to your own hot sauce while you are on an alkaline diet try using lemon or lime juice. As mentioned earlier when metabolised by the body, the acids in citrus fruit like lemons and limes have an alkalizing effect.


Related Questions

Does the alkaline diet really work? Consuming a diet containing predominantly alkaline foods has shown to have little effect on blood pH levels and has limited to no effect on the bodies pH overall. However, the negative effects of certain health conditions such as acid reflux disease can be reduced by consuming alkaline foods.

How do I reduce acidity when making chilli sauce? The best way to reduce the acidity of a chilli sauce is to preserve the sauce without the use of acids. This can be done using salt, oil or other non-acidic preservatives. Another option is to freeze your sauce or produce it regularly in small batches so that it does not require a preservative.

Do peppers cause acid reflux? Many spicy foods are known to exacerbate the symptoms of acid reflux. Capsaicin in chilli peppers may decrease the rate of digestion which increases the likelihood of acid reflux occurring. The burning sensation created by capsaicin can also compound the discomfort experienced from acid reflux.