Why is it that I always get nauseous, sometimes to the point of vomiting, whenever I drink tea while I’m dehydrated and/or unfed, but I can drink energy drinks like Red Bull and NOS whenever I damn well please without a problem? This makes no sense to me.
So, two things. First off, I am not a doctor, so not only should you not take anything I say as medical advice, but most of this is speculation on the part of someone without a full degree in a scientific field. Second, I combed through articles and evidence without finding anything I would consider conclusive.
First I’ll take a moment to explain why coffee can be hard on the stomach. It’s often said that it’s the acidity in coffee that causes problems, but this is probably not the case. Coffee generally has a pH of around 5. Your stomach, on the other hand, can range from a pH of 1-2 soon after eating, to a pH of 4-5 after digestion is complete. So, even at it’s least acidic, coffee in and of itself is not going to cause a drop in pH in your stomach. Also, Red Bull, like other carbonated beverages, tends to be MORE acidic than coffee, so if acid were the culprit, you’d most likely see a different scenario here.
The reason coffee and other caffeine-containing beverages can cause nausea has more to do with how your stomach works. The main enzyme at work in the stomach after eating is Pepsin. Pepsin breaks down proteins. Your stomach is also made, in large part, of protein. This could get bad pretty quickly, so there are mechanisms for protecting the stomach from the harsh chemicals needed to break down and then digest your food.
One of these mechanisms has to do with the interaction of hydrochloric acid and pepsin’s chemical precursor, pepsinogen. Neither of these chemicals are released into the stomach until you eat or drink something (and water will not trigger this mechanism.) When you consume something, your body signals the stomach to release both hydrocholric acid and pepsinogen. In this highly acidic environment, pepsinogen turns into pepsin and begins to digest proteins. Which is great, if there’s protein there to digest. If not, it can cause problems. This is part of the reason people with ulcers are encouraged not to drink coffee.
I looked into several things when researching your question. First, I looked up the nutrition facts for coffee, tea, and Red Bull, and looked for differences. Now, keep in mind that nutrition facts only trace certain things. Carbs, fats, protein, vitamins, some minerals, etc. They account for most of what makes up a food, but not all, so there are necessarily gaps in what I was able to find.
One notable difference is that energy drinks like Red Bull tend to contain B vitamins. There is a lot of hearsay online about B vitamins helping to abate nausea. I did manage to find two reputable articles linking vitamin B6 to the reduction of nausea in pregnant women. They can be found here and here. In the interest of full disclosure, I am going by the abstracts since I do not have a paid registration to PubMed. Both abstracts discuss, briefly, the research methodology and results. In both cases, the experimental groups were given doses of vitamin B6 ranging from 1.28 mg to 75 mg (3 doses of 25 mg each.) All of the groups that were given vitamin B6 showed a reduction in the severity of symptoms, and the first article indicates that the difference in symptom reduction between doses of 1.28mg and 10mg was likely not significant.
There are lots of reasons why B6 may still not be the culprit. First, the study was conducted on pregnant women, who are nauseous because of their pregnancy. Second, this involved consistent supplementation and plasma B6 concentration. The doses were taken orally, so it’s possible that ingesting B6 could have a quick effect, but it’s also possible that it needs to be fully absorbed into the body to have any affect. Without reading the full articles, it’s hard to tell if the mechanism by which B6 helps with pregnancy-related nausea would also make it useful for alleviating other kinds of nausea. Possible, but possibly a stretch. I was unable to find any concrete information regarding the other B vitamins contained in Red Bull.
So why do you get nauseous from coffee and not Red Bull? I have a couple ideas of why this might be happening for you, though I should note that a lot of people also report nausea when they drink Red Bull and other energy drinks. First, caffeine on it’s own is an acid secretagogue, which is a very jargony way of saying that caffeine is enough to stimulate the release of stomach acid, even though it does not itself have any food value in it. Most things that get your stomach going trigger that release of acid because they actually contain things you need to digest.
And no, there isn’t a lot of protein in Red Bull for that pepsin to act on, but there is twice as much as there is in coffee, while Red Bull also contains almost 20 fewer milligrams of caffeine per cup. It could be that the combination of more protein and less caffeine is enough to lessen the blow to your stomach. Not being a food chemist or a doctor, I don’t know how much protein is enough. For reference, though, coffee has 0.3g of protein, while Red Bull has 0.6g. To give you a basis for comparison, a saltine cracker has 0.3 grams of protein.
Basically, as far as my research was able to discover, there is no smoking gun here. It might pay off to eat something when you drink coffee or tea if you find that it tends to make you feel nauseous. Because some people report nausea with energy drinks as well, I suspect this might be one of those things that is caused by your unique body chemistry, or by some compound in tea and coffee that I was not able to find information on.
Is anyone out there able to offer more insight on this? I’d love to hear from you.