Science-Based Guide
Alkaline Water and Acid Reflux: What the Research Says
An evidence-based look at what peer-reviewed science tells us about alkaline water’s potential role in managing acid reflux symptoms.
Science-Based Guide
An evidence-based look at what peer-reviewed science tells us about alkaline water’s potential role in managing acid reflux symptoms.
Medical Disclaimer: This content is for educational purposes only and does not constitute medical advice. Always consult your healthcare provider before making changes to your diet or treatment plan.
Acid reflux, clinically known as gastroesophageal reflux disease (GERD), occurs when stomach acid flows back into the oesophagus. This backwash can irritate the lining of the oesophagus, causing a burning sensation commonly known as heartburn.
It is one of the most common gastrointestinal conditions worldwide. In South Africa, studies suggest that GERD affects a significant portion of the adult population, with prevalence rates estimated between 20% and 30% in some surveys. The condition has become more common alongside changes in diet and lifestyle.
The most recognisable symptoms include a burning sensation in the chest (heartburn), regurgitation of food or sour liquid, difficulty swallowing, and a sensation of a lump in the throat. Some people also experience chronic cough, hoarseness, or worsening asthma symptoms.
Conventional management of acid reflux typically includes lifestyle modifications such as dietary changes, weight management, and elevating the head of the bed during sleep. Medical treatments range from over-the-counter antacids and H2 receptor blockers to proton pump inhibitors (PPIs) prescribed by healthcare providers.
A key factor in reflux-related tissue damage is an enzyme called pepsin. Pepsin is a digestive enzyme produced in the stomach that breaks down proteins. When stomach contents reflux into the oesophagus and throat, pepsin can adhere to the tissue lining and remain active even after the acid has been cleared. This persistent enzymatic activity is believed to contribute to ongoing tissue irritation and damage.
The most widely cited study on this topic was conducted by Dr Jamie A. Koufman and Dr Nikki Johnston, published in 2012 in the Annals of Otology, Rhinology & Laryngology, a peer-reviewed medical journal.
Peer-Reviewed Research
Published in a respected otolaryngology journal
"Unlike conventional drinking water, pH 8.8 alkaline water instantly denatures pepsin, rendering it permanently inactive. In addition, it has good acid-buffering capacity."
Source: Koufman, J.A. & Johnston, N. (2012). "Potential Benefits of pH 8.8 Alkaline Drinking Water as an Adjunct in the Treatment of Reflux Disease." Annals of Otology, Rhinology & Laryngology, 121(7), 431–434.
The study examined the effect of alkaline water with a pH of 8.8 on pepsin activity in laboratory conditions. The researchers found that water at this pH level irreversibly denatured (permanently inactivated) human pepsin. They also found that alkaline water had good acid-buffering capacity, meaning it could help neutralise hydrochloric acid in the stomach.
It is essential to understand the scope of these findings. This was an in vitro study, meaning the experiments were conducted in a laboratory setting rather than inside the human body. The researchers demonstrated a mechanism by which alkaline water may be beneficial, but this is not the same as proving clinical effectiveness in patients.
The study’s authors themselves positioned alkaline water as a potential adjunct (a complementary addition) to standard reflux treatment, not as a standalone therapy. Further clinical research involving human subjects is needed to fully establish how these laboratory findings translate to real-world symptom relief.
To understand why pH is relevant to acid reflux, it helps to know how pepsin behaves at different acidity levels.
Pepsin is most active at highly acidic pH levels (around pH 2). As pH increases (becomes less acidic), pepsin activity decreases. However, at mildly elevated pH levels, pepsin is merely inactivated temporarily. It can be reactivated when the pH drops again, which is why reflux episodes can cause repeated irritation.
What the Koufman and Johnston study found significant was that at pH 8.8, the denaturation of pepsin was irreversible. The enzyme was not just temporarily inactivated but permanently destroyed. This is what distinguishes the potential role of alkaline water from simply drinking regular water, which typically has a pH between 6.5 and 7.5.
pH Scale Reference
Beyond pepsin denaturation, the study also noted that alkaline water demonstrated good acid-buffering capacity. This means it may help maintain a higher pH in the oesophageal environment for longer than regular water. Standard tap water, while it can temporarily dilute acid, does not have the same buffering effect.
Transparency matters. While the research is promising, it is important to be clear about the boundaries of what alkaline water can and cannot do.
It is not a cure for acid reflux or GERD. No water, regardless of pH, can cure a structural or chronic digestive condition.
It does not replace prescribed medication. If your doctor has prescribed PPIs, H2 blockers, or other treatments, do not stop or change your medication based on this information.
Laboratory results do not guarantee clinical results. The Koufman and Johnston study was conducted in vitro. How these findings translate to outcomes inside the human digestive system requires further research.
It is not suitable for everyone. People with kidney conditions or those taking certain medications should consult their healthcare provider before changing their water intake.
What the evidence does suggest is that alkaline water may serve as a useful complement to conventional reflux management strategies. It is one factor among many in a holistic approach to digestive health that includes diet, lifestyle, and medical treatment where necessary.
Designer Water is a South African premium alkaline water with a natural pH of 10, which exceeds the pH 8.8 threshold examined in the Koufman and Johnston study. Produced in Midrand, Gauteng, every bottle meets rigorous quality standards.
Designer Water contains naturally occurring minerals including calcium, magnesium, and potassium. Every batch is tested to ensure consistent pH and mineral content, so you know exactly what you are drinking with every bottle.
Available in 330ml, 500ml, 750ml, 1L, 5L, and 10L sizes across South Africa.
Available online and at selected retailers across South Africa.
A 2012 laboratory study published in the Annals of Otology, Rhinology & Laryngology found that alkaline water with a pH of 8.8 irreversibly denatured pepsin in vitro, suggesting it may have a role as a complement to standard reflux management. However, this was a laboratory finding, not a clinical trial, and more research is needed. Alkaline water should not replace medical treatment for acid reflux. Always consult your healthcare provider.
The Koufman and Johnston (2012) study specifically examined water at pH 8.8 and found it was effective at denaturing pepsin in laboratory conditions. Water at this pH level or above may offer some benefit as part of a broader reflux management approach. Designer Water has a natural pH of 10, which exceeds the threshold examined in the study. That said, pH alone is not a treatment for acid reflux, and individual results will vary.
For most healthy adults, drinking alkaline water daily is considered safe. Designer Water is SANBWA-accredited, ISO 22000-certified, Kosher, and Halal certified, ensuring consistent quality and safety. If you have kidney disease or take medications that affect kidney function, consult your healthcare provider before making any changes to your water intake.
No. Alkaline water should never be used as a replacement for prescribed medication or medical treatment. The available research suggests it may serve as a complementary addition to your existing treatment plan. Always follow your healthcare provider’s recommendations regarding medication and treatment.
Designer Water contains naturally occurring minerals including calcium (Ca), magnesium (Mg), and potassium (K). Every batch is tested to ensure consistent mineral content and pH levels. The water is produced under ISO 22000 food safety management standards with SANBWA accreditation.
Important Disclaimer
This content is for educational purposes only and does not constitute medical advice, diagnosis, or treatment. The research cited describes laboratory findings that have not been confirmed through large-scale clinical trials. Individual results may vary. Always consult a qualified healthcare provider before making changes to your diet, hydration, or treatment plan. Designer Water makes no claims that its products treat, cure, or prevent any disease or medical condition.
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