The Claim

Among individuals with confirmed Helicobacter pylori infection, the prevalence of cagA-positive strains is lower in those with Hashimoto’s thyroiditis (39%) than in those without autoimmune disease (64%), with no statistically significant difference.

Source: Association between autoimmune thyroid disease and presence of CagA and gastric intestinal metaplasia among patients with H. pylori: a cross-sectional endoscopic study

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
58score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

In people infected with Helicobacter pylori, those diagnosed with Hashimoto’s thyroiditis have a lower rate of infection with cagA-positive bacterial strains compared to those without Hashimoto’s thyroiditis, though the difference is not statistically significant.

See the scientific wording

Among individuals with confirmed Helicobacter pylori infection, those with Hashimoto’s thyroiditis show a non-significant trend toward lower prevalence of cagA-positive strains (39%) compared to those without autoimmune disease (64%), suggesting a possible inverse association that requires further investigation.

Why this might work

When H. pylori bacteria with the CagA protein infect the stomach, they trigger strong inflammation and release a protein that looks like parts of the thyroid. This confuses the immune system, causing it to attack the thyroid gland and reduce the chance of the bacteria surviving in people who already have thyroid autoimmunity.

Suggested mechanismbased on 1 study

What the research says

1 study
  1. Study: Association between autoimmune thyroid disease and presence of CagA and gastric intestinal metaplasia among patients with H. pylori: a cross-sectional endoscopic study

    People with Hashimoto’s thyroiditis who have H. pylori are less likely to have the more harmful version of the bacteria (cagA-positive) than people without thyroid disease — but this pattern isn’t strong enough to be certain yet, so more research is needed.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.