Dismiss Notice
Join Physics Forums Today!

Vinegar and stomach acid pH

  1. Apr 11, 2008 #1


    User Avatar
    Gold Member

    "By taking a little apple cider vinegar before a meal, you can increase stomach acidity and thereby improve digestion and nutrient uptake. "

    But since vinegar is less acidic than stomach acid wouldn't it follow that vinegar would reduce stomach pH? (unless the watery contents of vinegar flux out of the stomach at a higher rate than the acidic contents of vinegar?)
  2. jcsd
  3. Apr 12, 2008 #2

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    I think you are correct. For older people, stomach acidity (pH) may go up, so maybe in that case vinegar would lower pH. For people with normal pH I don't see how it could lower pH overall. My only guess would be that adding acid lowers the pH of chyme (food) before the stomach acid has started to be produced.

    Dunno for sure.
  4. Apr 12, 2008 #3


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    Please provide the source of your quote so we can see it in context.
  5. Apr 12, 2008 #4


    User Avatar

    Staff: Mentor

    It's all "health food" misinformation. Apple cider vinegar has long been touted as a "cure all". I read the book on "Folk Medicine" by Jarvis decades ago that was a catalyst for the health food misinformation and basic scamming of people that pay a small fortune for the vinegar at a health food store. :rolleyes:

    This is an excellent article about apple cider vinegar myths and facts.

  6. Apr 25, 2008 #5


    User Avatar
    Gold Member

    Okay, here's a quote: (from a more credible source) [although related to acids in general, not just vinegar]


  7. Mar 10, 2009 #6
    Hey there-
    Any food or drink which introduces hydrogen ions into the contents of the stomach will make it more acidic (lower the pH). The stomach lining releases concentrated hydrochloric acid into the lumen of the stomach in response to stretching (when food fills it). The pH of the food and drink in the stomach averages with the pH of the hydrochloric acid (sorta, acid/base chemistry is a bit too complex for this post). This means that if the food starts at a lower pH (more acidic), the end result will be lower than if your food started near a neutral pH.
    Please note: I am a student of cellular and molecular biology in my last semester. I am firmly grounded in the world of science and hate quackery and pseudo-science. So please do not take my post as a confirmation of the claims made by the "vinegar will cure anything that ails you" people.
    Last edited: Mar 10, 2009
  8. Apr 19, 2009 #7
    im sorry but if everyone is going to be a source and reference nazi on this forum i have to point out that your "excellent article" is pretty pathetic. how many references are there? none. how many facts are in the article? none. the author lists a bunch of claims and then responds by making claims. what studies were done, who conducted them, why is the bibliography a link to the article you are already reading? has reading one book really turned you into a bitter skeptic? health food is a scam? id rather drink this really expensive $3 vinegar the rest of my life than take a single chemical pill which from day one has more known side effects than known benefits. it really makes me chuckle that people waste so much energy debunking what they already think of as a harmless placebo. the world is full of chemically imbalanced people, so instead of promoting organic "health food" and dealing with the cause, lets keep pumping out nutrient deficient foods and drown the world in artificially produced chemicals that mask the symptoms! oh and we can make billions while doing it!!! GENIUS !!!
  9. Apr 20, 2009 #8


    User Avatar
    Science Advisor

    Nonsense. Anything that contains protons contains counterions and is in equillibrium with a pKa/pKb. Depending on which, it may not increase stomach acidity one bit.

    Well the original post was pretty explicitly referencing the facts of acid/base chemistry so I'd say it's quite relevant.
  10. Apr 20, 2009 #9


    User Avatar

    Staff: Mentor

    I just read it again, and it's an excellent article discussing vinegar myths. I can see why it would upset someone that believes in the hype.

    Ok, here you go.

  11. Apr 20, 2009 #10
    saying the same thing twice doesnt make it true. also, you are assuming i "believe the hype", which i dont. what i had a problem with was you claiming there is "health food misinformation and basic scamming of people". then to prove your point, you use an article that might as well be counter misinformation, since it proves nothing. then you give me another article with more of the same "there is not enough scientific evidence to form a clear conclusion" and "There may be long-term risks". not enough scientific evidence and the chance that there may be risks doesnt seem to stop major commercial food companies from adding things like aspartame, msg and other toxic chemical additives. if you want to eat right, always think in terms of what was being consumed by humans 12,000 years ago, or rather what wasn't being consumed by them. i'll be the first to point out, they werent drinking vinegar ;)
  12. Apr 20, 2009 #11


    User Avatar

    Staff: Mentor

    Actually my mom is one that believes in all of those myths. I gave her that book on Vermont Folk Medicine to read. I thought she'd like it since she LOVED vinegar.

    Growing up, she put vinegar on almost everything. Any green leafy vegetable, lettuce, spinach, collards, mustard and turnip greens, avocados, asparagus. When she tried to feed me cold tripe covered with oil and vinegar, I finally put my foot down.

    The thing is, myths abound. They take a little fact and blow it all out of proportion and no one is going to fund scientific research specifically to debunk food myths. Vinegar has some small qualities that can be considered good for some things. So does wine. :tongue2: But the danger in going along with the myths or the stretching of the truth, is that people will self diagnose and then self prescribe a home remedy, not understanding what they are doing or if they are putting themselves at risk. Obviously, we don't condone that here.
  13. Apr 21, 2009 #12
    fair enough. organic food and farming is one of the few simple, yet very positive (for the planet and people) movements humans are involved in right now. im guessing you were referring mostly to the vinegar when you said "health food misinformation and basic scamming". since vinegar isnt really a food i just wanted to make sure you werent saying that "health food" is itself a scam. a very good book (which is thoroughly referenced) called "ten thousand years from eden" tells of a study that observed 90% more nutrient content in organic plants compared to commercially grown specimens of the same type.
  14. Apr 21, 2009 #13


    User Avatar

    Staff: Mentor

    Do you have a link? Because all of the studies I've read show no nutritive difference between "organic" and regular farm grown.
  15. Apr 21, 2009 #14

    Chapter Nine "When is a Tomato a Tomato?"

    "Comparisons of organic and commercially grown foods are also revealing. Smith (1993), over a two year period, purchased apples, pears, potatoes, wheat and corn from markets in Chicago. These were analyzed by Doctor's Data Laboratory in west Chicago. The vegetables organically grown had on average, over 90 percent more nutritional elements than similar commercially grown food. Sweet corn had 2.5 times more nutrients."
    Last edited: Apr 21, 2009
  16. Apr 21, 2009 #15


    User Avatar

    Staff: Mentor

  17. Apr 21, 2009 #16

    i guess you responded before i added the quote. if you are actually interested in more than internet hearsay i would highly recommend reading that book. it will spell it all out for you, and cite where the information came from. the author is a Ph.D. and is an older gentleman, so its a lifetime of wisdom packed into one book. it is written clearly so anyone can understand and becomes more technical toward the end as he starts to explain the biochemistry behind it.

    oh and where is your link or source for the study with the nutritional analysis to support the claim "One head of cabbage grown *organically*, one head of cabbge grown normally. Nutritionally they are identical." ?
    Last edited: Apr 22, 2009
  18. Apr 22, 2009 #17


    User Avatar
    Homework Helper
    Gold Member

    I leave aside the nutritional and digestive things.

    You seem to make physical chemical mistakes here.

    From how you write it you seem to want to say "since vinegar is less acidic than stomach acid wouldn't it follow that vinegar would reduce stomach acidity" . But that = increase, not decrease, stomach pH.

    Then you seem to think that a weaker acid makes a stronger acid less acidic. No: the vinegar would have practically only the effect of the same volume of water. Apart from that effect, two acids together are more acid than either alone, not something in between.

    We discussed that here not long ago: https://www.physicsforums.com/showpost.php?p=2131463&postcount=6

    I think if you mix the two it will give you a pH almost the same as if you put the same volume of water as of weak acid, but will be very slightly more acid than that. In other words the effect is essentially no different from dilution.

    Instead of complicating by dilution let us just compare a given concentration of strong acid with that same concentration of the strong acid but the solution also containing weak acid. (I am assuming the weak acid not extremely more concentrated than the weak.) Now it is true that, compared with when the weak acid was on its own, dissociated ions e.g. Ac- will take on protons to form HAc. But it cannot take on more protons than it releases into the water in the solution of weak acid of that concentration! Not more, so a small bit less, that little bit is the extra protons added to the solution of strong acid when the weak one is added ideally without dilution.

    It is instructive to make a full calculation. I found, subject to correction , that when the strong and the weak acids are equimolar the [H+] is higher than that of the strong acid alone by Ka .

    Here I correct just at the last word an error I made on that post which I could not correct becase the thread was locked. :cry: (The effect however is quantitatively negligible, though a useful excercise.)
  19. Dec 21, 2010 #18
    To everyone

    I have a problem with low amount of HCL. The ph isn't the problem and taking vineager (apple cider because I like the taste) does make a diference so I don't understand what the issue is. I have found that what works for me and my circumstances may not work as well for you. This is probably due to the fact that I have other factors that contribute to my requirements.

    As to repeating what someone else says is the gospel truth is fulish. I have celiacs and myasthenia gravis and a load of doctors that have told me what I had to do and that I would never get of the dangerous drugs, well they're wrong. Its great when someone tells you what happened to them and what they did to get a resolution but remember we are not doctors and none of you know all of the issues. So support each other with information that YOU know has worked for you.

  20. Dec 25, 2010 #19


    User Avatar
    Gold Member

    Hm, this sentence confuses me. The extra volume of water would *definitely* dilute the acid. In other words, it would raise the pH. So if you added vinegar instead of water, you would still raise the pH (since the volume of vinegar would probably be a good fraction of the total volume of stomach acid, and since the vinegar is usually well-diluted anyways) of the whole solution - just not as much as if you just added water? (but still more than adding nothing at all?) There would be far more neutral water molecules with the extra addition, and just a few more hydronium ions (and the ratio of them would just decrease)
    Last edited: Dec 25, 2010
  21. Dec 25, 2010 #20
    vinegar seems to affect digestion in a good way, so enjoy your vinegar.



    as for how it affects stomach acidity on an empty stomach, that's hard to say. the stomach is not normally secreting much acid then. that's why you want to take calcium carbonate supplements with a meal: to dissolve the carbonate releasing CO2 and make the Ca++ ions available for absorption. otherwise, you pass much of it as sand. calcium citrate (like the citrical commercials paul harvey did aimed at your parents with low stomach acidity) you can take whenever.

Have something to add?
Similar Discussions: Vinegar and stomach acid pH
  1. Shrinking your stomach (Replies: 7)

  2. Amino acids (Replies: 5)