Could Low Stomach Acid Be Impacting Your Ferritin Levels and Bone Health? 8 Steps to Better Mineral Absorption

Why stomach acid and digestive enzymes matter with vitamins and minerals including iron, calcium and B12

Did you know that humans are meant to have a very acidic stomach, with a pH of 1.0-2.0 making it much more similar to a scavenging crow than a cow chewing grass! This stomach acid (which is hydrochloric acid, or HCI) is essential to not only digestive health but the absorption and activation of vitamins and minerals such as B12, iron, calcium and magnesium! 

If you have low ferritin, anaemia, osteoporosis or uncomfortable digestive symptoms such as bloating, abdominal pain, reflux or constipation, before you purchase expensive supplements, consider whether improving stomach acid, bile and pancreatic enzyme function could address the root cause.

Digestion begins in the brain

Digestion begins in the brain. When you smell, see or think about food, the vagus nerve is stimulated and  triggers the production and release of hydrochloric acid (HCl) in the parietal cells in the stomach. This has many effects:

1. This initial acid release prepares the stomach to break down incoming food, particularly proteins in meat

2. Stomach acid is essential for vitamins and minerals from the food matrices allowing them to bind to carrier proteins in the small intestine for absorption. In particular, B12, iron, calcium and magnesium require HCI levels. This is why osteoporosis ( low calcium and magnesium) and anaemia (low iron and B12) can result from low stomach acid! 

3. The release of HCL messages the pancreas to release pancreatic juice and  sodium bicarbonate into the small intestine. This raises the pH from 6.1 up to 7.5 making the small intestine alkaline. The digestive enzymes in the pancreatic juice can then get to work digesting proteins, fats and carbohydrates to be absorbed by the human. 

4. Stomach acid, bile and digestive enzymes are all anti-microbial, when in correct amounts, they destroy most ingested bacteria, viruses and funghi, preventing gastrointestinal infections and small intestinal bacterial overgrowth (SIBO).

Consequences of low stomach acid and digestive enzymes

1. Enzymes are not activated:

When stomach acid levels are low (also known as hypochlorhydria), there is no message to the pancreas to release pancreatic juice and no digestive enzymes which should include pancreatic amylase (carbs), lipase (fats), trypsin (proteins), and brush border enzymes including lactase, sucrase, and maltase

2. Bacteria are not killed off:

Low stomach acid is a major risk factor for SIBO as food is not  adequately sanitised, allowing bacteria to survive and flourish in the small intestine. This causes undigested food to ferment, leading to significant bloating, abdominal pain, diarrhoea, and nutrient deficiencies. 

3. Nutrients are not absorbed:

Not only do they feed on carbohydrates causing gut symptoms, these bacteria destroy the intestinal wall lining and the brush boarder enzymes, causing inflammation and malabsorption. In particular, Small Intestinal Bacterial Overgrowth (SIBO) can cause a Vitamin B12 deficiency because the excess bacteria in the small intestine consume the B12 before your body can absorb it. The bacteria in SIBO compete with the host for essential nutrients, and Vitamin B12 is one of the most commonly affected. Remember the small intestine is meant for human absorption and the large intestine is to feed the microbiome!

The symptoms of low acid, low enzymes and SIBO overlap and include:

• Bloating and abdominal distension

• Abdominal pain and discomfort

• Nausea and indigestion

• Diarrhoea and constipation

• Can't eat red meat, feeling full for many hours after eating

• Acne, rosacea or psoriasis

  
  

As a result of low pancreatic enzymes and SIBO you may also experience:

• Decreased absorption of fat soluble vitamins A-D-E and K

• Decreased absorption of magnesium and calcium ( predisposing to osteoporosis) and iron and B12 ( can lead to anaemia)

• Fatty stools and indigested food in stools

Why does hypochlorhydria occur?

1. Proton Pump Inhibitors such as esomeprazole (Nexium), and pantoprazole (Somac) are taken for heartburn, and their mode of action is to suppress stomach acid production in the parietal cells. As a result, long term usage can be associated with low calcium and B12 levels. 

2. Chronic stress can lead to hypochlorhydria by disrupting the body's digestive processes, often shifting it from “rest and digest” into a "fight or flight" mode that depresses gastric function. Sustained, high stress can lead to deficiencies in zinc and B vitamins, which are crucial for producing stomach acid.

3. Helicobacter pylori (H.pylori) is a bacterium that survives the stomach's harsh acid by producing urease, an enzyme that neutralises acid in the parietal cells with ammonia. This allows it to colonise the lining, causing inflammation, gastritis, and peptic ulcers by breaking down protective mucus. It is a major cause of chronic indigestion and stomach cancer risk. It is diagnosed by breath test or endoscopy and treated with antibiotics.

4. Ageing is associated with structural and functional decline in all organs and systems, including the digestive system. This is compounded if older people cannot access nutritious food, have an H pylori infection, are on PPI’s or if dentures don't fit. 

   
   

Digestive enzyme deficiency can in itself be related to:

• Unmanaged hypothyroidism

• Autoimmune disease

• Coeliac disease

• Inflammatory bowel disease

• Zinc deficiency

8 Practical steps to improve digestion and nutrient absorption

• 1. Ageing is going to happen but I like all my clients over the age of 70 to be on a sublingual B12 supplement. I also make sure they have affordable, bioavailable sources of protein (and nutrition in general) and that if they have dentures, that they fit!

• 2. Antacids and proton pump inhibitor medication is necessary and you should take as prescribed. Of course, no-one should tolerate reflux, but it’s a good idea to work with a Clinical Nutritionist on why the lower oesophageal sphincter (LES), a circular muscle acting as a valve between the oesophagus and stomach is weakened or relaxed inappropriately, allowing stomach acid to flow backward. This is often the irritation causing symptoms like heartburn and regurgitation, often worsened by obesity, smoking, pregnancy, or a hiatal hernia.

  If you are on long term PPI’s you may need magnesium, B12 and/ or  calcium supplementation 

• 3. Even if you’re stressed and busy and have to eat at the desk, take a moment to smell, see and anticipate food to start digestion. You can ’trick’ your brain into ‘rest and digest’ by taking a few deep breaths as this signals to the brain that it’s OK to focus on digestion. Take your time and chew well!

• 4. Bitter foods and herbs stimulate stomach acid production by activating bitter taste receptors in the mouth and gut, initiating a nerve reflex that increases saliva, gastric juice, and digestive enzyme secretions. This process improves digestion, boosts nutrient absorption, and enhances bile flow, but can aggravate reflux in some.

  The compounds in bitters (e.g., in rocket, dandelion greens, kale, radicchio) stimulate a vagal nerve reflex that increases gastric motility and secretion of digestive juices.

  Bitter herbs are a tonic for the liver and I often recommend Iberogast as a liquid formulation designed to stimulate, regulate, and soothe the digestive tract.

• 5. Eat zinc rich foods: Adequate zinc is required for stomach acid production. Examples include pumpkin seeds, oysters lentils, and beef.

• 6. If you are struggling to eat protein and food feels like a brick in your stomach, soups and slow cooked meats are easier to digest than cold food or raw salads 

• 7. Papain is a proteolytic enzyme extracted from the papaya plant. Proteolytic enzymes help break proteins down into smaller protein fragments called peptides and amino acids. This is why papain is a popular ingredient in meat tenderizer.

  You can get papain from eating papaya or it is often in digestive enzyme supplements with bromelain, the enzyme in pineapple.

• 8. Digestive enzymes with betaine hydrochloride can be very useful. Some of my favourites include:

  * Orthoplex White Hydrozome: Combines Betaine hydrochloride, a source of hydrochloric acid and has a similar pH to stomach acid, glutamic acid and pepsin - a proteolytic enzyme involved in proper digestion

  * Biomedica Adalase: digestive enzymes, Vitamin A and D for immune and skin health

Low stomach acid and a deficiency of digestive enzymes can be a hidden driver of nutrient deficiencies, low ferritin, anaemia and poor bone health. Simple steps such as addressing stress, eating zinc-rich and bitter foods, using targeted digestive support, and checking for H. pylori or long-term PPI effects can restore digestion and absorption.

If you would like to discuss any of these strategies I mentioned above, please book an appointment on my website, www.bespokenutrition.com.au