Gastric acid level of humans must decrease in the future.
Level 5 - mechanism / opinion, no new human data
Mechanism-based reasoning and evolutionary hypothesis paper with no empirical data.
PubMed 33268958 · doi:10.3748/wjg.v26.i43.6706
What was done
The author formulated an evolutionary hypothesis through a narrative review, synthesizing observations on digestive physiology (tolerance of proton pump inhibitors and gastrectomy), comparative gastric pH between humans and scavenger species, and ancestral dietary conditions to theorize the future evolutionary trajectory of human gastric acid production.
What was found
The abstract reports no empirical data, sample sizes, or quantitative measurements. It notes qualitatively that digestion remains functional without stomach acid or following total gastrectomy, human gastric pH resembles that of carrion scavengers, and hypothesizes that human gastric acid production will gradually decrease over time if hygienic modern food environments persist.
Why it matters
It offers a theoretical evolutionary explanation for high human gastric acidity as primarily an antimicrobial barrier for scavenging rather than an indispensable digestive necessity.
Limits
The paper is purely speculative mechanism-based reasoning and opinion. The abstract provides no experimental tests, quantitative data, evolutionary modeling, or systematic literature review.
Cited by
- supports Human stomach pH is between 1.5 and 3, which matches the acidic stomach pH of carnivores like wolves.