Low Acid Coffee And Heartburn: Is it Proven to Work?
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Posted by Eric Troy on 06 Mar 2015 19:59




I have a confession to make. This may seem shocking, but it is the truth: I've been drinking coffee since I was five years old! My folks would start us children out with a lot of milk and a little coffee (plus sugar). It is what in the South we call "coffee milk" and it's related to Cambric Tea. The coffee would slowly increase and the milk would decrease. They didn't do this because they thought it important that we drink coffee. We would beg for it because we saw the adults drinking it and, in those days, nobody saw anything wrong with it. Well, despite all the zig-zag in the reputation of coffee, I still see nothing wrong with it. Except, I can't stop. I MUST have my coffee in the morning. Once I stopped for an entire year. The headaches at the beginning were terrible. After that, it was a year of misery, never feeling like myself. I want qualify this feeling, but finally gave in and got a cup of coffee one day (while studying for an exam), and it was like someone flicked a switch, the lights were back on!

Now, imagine a lifelong coffee drinker like myself, who not only loves his coffee, but needs it, couldn't drink it. I get occasional heartburn like anyone else. The same is true of millions and millions of people who get heartburn once a month to several times a month. This is not necessarily a big deal but if one of your favorite foods or beverages is a trigger, and even worse, if you feel somewhat dependent on it, you may try looking for attractive alternatives. What if coffee gave me heartburn? Coffee is acidic and is one of the prime heartburn and reflux triggers. It's not like I'm going to drink high-caffeine sodas or energy drinks in the morning. I'd probably end up popping caffeine pills.

Is it the Acid?

Most people assume that high-acid foods or beverages give them heartburn. However, this is not necessarily the case. The assumption that high-acid content means "high-acid stomach" is not always a correct one. Many things we think of as high-acid do not trigger excess stomach acid. For example, orange juice, despite its acidity, is alkaline. You might be thinking that orange juice gives you heartburn. Well, anything is possible but if you frequently suffer from acid reflux and you esophagus is already damaged and inflamed, it may well be that the orange juice is burning on the way down. The pain comes out to be the same, you have heartburn, but the mechanism is quite different than with other foods that trigger excess acid and help to cause that damage in the first place. The question is, does coffee do this?


green coffee beans have more acid than roasted beans

Before roasting, green coffee beans contain
more acid.

green coffee beans have more acid than roasted beans

Before roasting, green coffee beans contain
more acid.



Well, one of the problems of GERD (gastrointestinal reflux disease) is that the LES or lower esophageal sphincter is relaxed and loose. The LES is a ring of muscle that tightens down like a cinch and closes off the stomach from the esophagus. If this fails to happen, and, worse, you rest in a declining position, the contents of the stomach might migrate up into the esophagus. Sure, this happens to most everyone occasionally, but for others it is a chronic problem.

For most people coffee tightens the LES. However, for people with GERD, it seems to relax the LES. Not good. The next question, then, is whether coffee increases acid production. Hopefully you recognize that this is a different question than "how much acid it contains." Again, it turns out that coffee does indeed increase acid production. Before we continue, let's stop and take stock:

There are two main ways that food or beverages are thought to cause heartburn.

1. Highly acid foods or beverages, like citrus juices, irritate the lining of the esophagus on the way down. If the esophagus is already eroded from frequent acid reflux, this irritation will produce more severe heartburn symptoms.

2. Certain foods decrease the lower esophageal sphincter (LES) pressure, thus making it more likely to have reflux (termed gastroesophageal reflux).

3. Certain types of foods or beverages cause more acid secretion. This is not necessarily abnormal. For example, a high fat meal means more acid. But, if you combine a high fat meal with perhaps, coffee, which helps relax the LES…I think you're catching on.

There are many other mechanisms and questions we can ask, such as whether a large meal may be a worse culprit (it would seem so, right?). If you do suffer from frequent heartburn, you should be talking to your doctor about it. But we can ask some questions about coffee. First, let's talk about acid free coffee.

Low Acid or Acid Free Coffee

There are many coffees on the market which claim to be low-acid or acid free. I doubt that claims of NO acid are true, but you may have seen articles proclaiming that acid-free coffee is much more healthy than regular coffee. There are many inflated claims about the "acid related diseases" that coffee and other high-acid foods cause. I wouldn't put much stock in these claims. However, we can already see that if high acid foods are irritating the esophagus, then decreasing the acid content of coffee may make it less of a problem. But is it really possible to remove the acid from coffee and have it still be coffee?

Coffee has two main tastes, and these vary depending on the type of coffee and the way it is roasted. The two primary flavors, are bitterness and sourness. Sourness comes from acidity. Right off the bat, we can see that a less acid coffee should be a less sour coffee. This would also mean a different taste. If it were possible to decrease acidity while maintaining bitterness, you'd have more bitter, less sour. This may not be a good thing, depending on just what components are enhanced, and which ones are reduced.

green coffee beans have more acid than roasted beans

The degree of roasting affects the acid content. a ligther roast
has more acid. A darker roast has less acid. This medium roast should
be right in the middle, at a pH of 4.9 to 5.2

green coffee beans have more acid than roasted beans

The degree of roasting affects the acid content. a ligther roast
has more acid. A darker roast has less acid. This medium roast should
be right in the middle, at a pH of 4.9 to 5.2

From here, remember that I may use sourness or acidity to mean the same thing (I'm like that). To answer the question of whether less sourness is a bad thing, generally speaking, it is not. Most coffee gurus say a less sour and more bitter coffee is preferable. But, those coffee gurus can't keep their terminology straight. Because they like both high acid coffee and complain about sourness. Alkaloids are the primary components responsible for bitter flavors, and they are base chemicals, basically the chemical opposite of acid chemicals (glucosides and metallic ions can also contribute to bitterness). Oops. Minus one for the expert tasters.

Green coffee contains a mixture of different acids. Roasting decreases some of these acids, and also introduces new ones, albeit at low levels. When in a solution these acids are all disassociated and so can each contribute to the overall smell and flavor. Some acids may be more important than others to this experience. Then, there is the presence of pure hydrogen ions, but it is questioned how much this contributes to the aroma and flavor.

When companies produce "low acid coffees" they talk about pH levels. A higher pH means lower acid. A medium-roast arabica generally has a pH of 4.9 to 5.2, which is said to be pretty much optimum. Lighter roasts have more acid. Darker roasts have less acid. Perhaps you expected the opposite, since darker brews have stronger tastes. Regardless, just what acids are increased or decreased can contribute to the flavor, and although there are claims and opinions as to the type of acids that are affected, and how this optimizes the coffee experience, the pH doesn't tell you that, in itself.

Makers of low acid coffees will claim all sorts of mumbo-jumbo as to how they make their coffee less acid, and they may report a pH of 6 or even higher. The problem is that coffees with pH values this high are thought to be not so good. Flat tasting. Subjectively, how well these high pH values actually correlate with the perception of acidity is questionable. Instant coffees, by the way, tend to be more acid, especially due to their lower quality processing. They are sometimes treated with alkali. It is possible that other brands of low acid or acid free coffee are also treat this way. Alkali, in short, can be thought of acid's kryptonite. More alkaline solutions have a higher pH.

Do Lower Acid Coffees Produce Less Heartburn Symptoms?

According to this study, lower acid (treated) coffees may produce less symptoms, but it is variable. There have been other studies that have tried to determine the affect of lowered acid coffee on LES pressure, further confusing the issue, since LES pressure was still lowered in susceptible subjects. Regular "acid" coffee, however, still had a greater and more important effect. Is their undeniable proof that a low acid coffee will not cause you yourself to have heartburn? No. Is it possible that a low acid coffee will cause you less problems? Yes.

Will the coffee taste good to you? You would have to try different brands and find out if they help, and if they you like them. In general, they shouldn't hurt you. But, acid isn't the only thing that can be at work, here. What about the caffeine?

Does Decaf Coffee Cause Less Heartburn?

It seems that decaffeinated coffee may be a more promising route than low acid coffee. Decaf coffee is more strongly associated with a lack of LES pressure loss. In other words, decaf coffee seems to be less likely to relax the LES in coffee intolerant people. This study from 1996, The effect of decaffeination of coffee on gastro-oesophogeal reflux in patients with reflux disease, bears this out. Both regular and decaffeinated coffee can increase gastric acid secretion, but decaf coffee causes it to a lesser extent.

Caffeine alone does not really cause excess acid like regular or decaf coffee, however. It could be that there are various other compounds in coffee, which are necessarily reduced by decaffeination, that are responsible for this effect. The many variables and possibilities can be confusing, but switching to decaf may be much more likely to reduce or eliminate heartburn symptoms due to coffee.

Decaf coffee, for those who must have their morning coffee, is not an attractive solution. Clearly, low acid varieties would seem more attractive. It is still possible, as stated above, that choosing a low acid coffee may help. Puroast Low Acid coffee is a popular choice, claiming to contain 50% less acid. Many Amazon reviewers claim that it not only taste good but does not cause them heartburn. Only you can determine if this is true for you. The label image on the description page, by the way, reads 70% less acid, but this seems to be either a misprint or the wrong label. If you read the *important information** section, you will notice some of that ambiguity in terms I mentioned, with the description claiming that the special "Zenezuelan" roasting process claiming that bitter elements are reduced which in turn lowers the acid content. Acid is not responsible for bitter flavors. These come from other compounds in coffee. If you actually did reduce only bitter compounds, this may possibly have an effect on acid compounds, but it is doubtful that this is what the coffee roasters meant in their description. Franlky, while the coffee may indeed have half the acid (of an average arabica roast?) and it may be easier on your reflux symptoms, the "special process" sounds like poppycock.

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