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Absorption Issues

In addition to the effect grains have on the intestines, they also have an impact on stomach acid (HCl). HCl has 3 purposes in the stomach:


1. Activate the enzyme, pepsin, which breaks down protein (so the digestive enzymes can do their job to get the nutrients to the cells)1

2. Break down minerals, e.g. calcium, magnesium, etc. from food for absorption
3. Protect the body against most bacteria/micro-organisms in food2


The human body produces less stomach acid as we age.3 The symptoms of too much stomach acid (acid reflux, nausea, etc.) are also the symptoms of not having enough HCl ( Eating carbs/plants triggers digestive enzymes in the mouth and stomach, but meat protein signals the stomach to produce HCl.4


Without enough stomach acid:


1. Your body doesn’t get as much of the vitamins/nutrients in the food, which over time can lead to various deficiencies
2. Mineral absorption is reduced, which can contribute to osteoporosis because you’re not getting the calcium, magnesium, boron and other minerals you need for strong bones
3. Your body doesn’t get B12, which is only found in animal products. HCl activates pepsin which breaks down the meat so that B12 can be absorbed in the intestines. This vitamin is essential for neurological and heart health, and it is recommended that people who have gastric bypass surgery receive B12 shots for life so they don’t become deficient
4. You are more vulnerable to micro-organisms in the ingested food


In "Wheat Belly's" chapter on celiac, Dr. Davis states “55% of celiac sufferer have IBS-like symptoms and between 7 and 19 percent have acid reflux.” He notes “75% of celiac sufferers obtain relief from acid reflux with wheat removal.”5 For those of us who have urpy cats, we’ve treated the urps with medications like Pepcid, which stops the production of stomach acid. This prevents nutrient absorption as well, because as stated earlier, stomach acid is needed to break down protein and help the body absorb minerals.


Many pet parents, myself included, use acid-blockers to help our special-needs pets to keep their food down and/or help with nausea. Sometimes it’s necessary, and the reality is that they won’t get anything out of their food if they throw it up. However, I get concerned when it’s used on a regular and/or long-term basis. These medications were never intended for long-term use, and shutting down the production of stomach acid prevents proper digestion and nutrient absorption. As I learned about human digestion, I started to wonder:


1. What IF: over time, people eating a high-carb diet “train” their stomach to produce less acid, since the enzymes, not acid, digest the plants?
2. What IF: like humans, our pets produce less stomach acid as they age?
3. If there’s not enough acid to break down the protein, does that contribute to kidney and/or gallstones, since acid is needed to break down the minerals (calcium, magnesium, etc.) in the food?


Assuming the above are true, I began to wonder if some cats that were on a high-carb diet (kibble) for years had “trained“ their stomachs to produce less acid. They may not show any signs of tummy upset while they‘re young, but as they get older (again, assuming like humans they produce less acid as the age), perhaps those signs appear. A vet will then recommend an acid blocker like Pepcid. However, just like “human” doctors, they are basing that diagnosis on the symptoms. Unless they have tested the cat’s (or person’s) stomach acid levels, they are assuming that the issue is too MUCH acid when the opposite may be the case.


Mr. Fluffy was fed kibble and canned food (with grains) for over 6 years. What if that “trained” his body to produce less HCl? If that’s the case, then what can you give a cat or dog that’s natural and acidic to help add acid in the stomach and assist with digestion? I decided to use organic apple cider vinegar (ACV) with the “mother” in it. Adding a drop or two might be enough to help him digest his now-grain-free meals.


An online friend of mine has a cat similar to Mr. Fluffy in age and GI issues. This cat was also kibble-fed for about 5-6 years and is also now on a grain-free canned and partial raw diet. She would also burp, which can indicate that the food is “fermenting” in the stomach due to lack of HCl breaking down the food. I suggested the ACV in June 2014, and these are the results to date:


Note: This cat gets several small meals during the day and even in the middle of the night in order to keep the vomiting to a minimum and get enough food in her. She gets 2 drops of ACV in two of those meals, along with slippery elm bark or Vet's-Best, since her owner is concerned that the mucilage from either of those two supplements may interfere with nutrient absorption.  She is given another meal immediately afterwards to "wash" the ACV off of her teeth.


1. Cat seemed to like it, except if mixed in raw
2. Smaller feces (getting more out of her food)
3. Improved energy
4. Longer time period between vomiting episodes (previously every 3 days, now every 12 days)
5. Fur now passing through GI system and in stool instead of blocking her intestines, which caused vomiting
6. Eaten grass, which would sit in her stomach for up to 8 days causing vomiting and stomach upset, comes back up in 3 days or gets passed in stool
7. Able to go longer between meals if fed in tiny, tiny portions upon resuming feeding
8. Whiskers got long and lush. This also happened when given digestive enzymes, however she had less energy and the pet parent saw no other improvements or changes, so she stopped adding the enzymes to the food. Given that digestive enzymes need HCl to break down the food so they can do their job better, I suspect that the additional acid is helping them to be more effective.
9. Ear inflammation disappeared


Note how 4, 5 and 6 are all motility issues. I believe that the ACV helps with those issues because she’s getting more calcium and magnesium out of her food, which helps muscles contract and relax, including the muscles that move food along the digestive tract. This cat also has a history of struvite crystals, and it’s my hope that the ACV will help with that as well, because she’ll be getting the minerals out of her food instead of the minerals just staying in the food, to possibly end up in her bladder. I have no proof of this; it’s all theoretical.


I also hope that, in time, her body will heal itself enough that it will begin to produce enough stomach acid on it’s own, and the ACV will no longer be necessary. It’s also possible, though, that years of a carb-based diet could have altered the stomach’s pH permanently, but I doubt there are studies for that.


I should note that ACV may damage tooth enamel, though I think such a tiny amount mixed in food may not be enough to cause a problem. That said, I also think if the cat is being fed organs and raw bone or bone broth, the minerals obtained will be sufficient to repair/rebuild the teeth and keep them strong, esp. if the added stomach acid is helping to break down the minerals so the body can use them. The ACV will also help in breaking down the meat protein so the enzymes can better do their job getting the minerals where they need to go. And those minerals are vitally important for bone and dental health, as well as overall health.


ACV may directly affect the pH of urine passed after that meal.


SIDE NOTE: I and others have seen articles that state that ACV alkalizes and some that say it acidifies. I suspect the reality is that it’s acid in the stomach, and when it gets to the intestines, the bile from the gallbladder alkalizes, as it does humans.




1 Loomis, HF. Enzymes, The Key to Health Vol 1, The Fundamentals 2012; 94
2 Ballentine, R. Diet & Nutrition, A Holistic Approach 2014; 318
3 Ballentine, R. Diet & Nutrition, A Holistic Approach 2014; 322
4 Ballentine, R. Diet & Nutrition, A Holistic Approach 2014; 322
5 Davis W. Wheat Belly 2011; 93

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