Evidence Based

Health Benefits of L. johnsonii + Safety

Written by Biljana Novkovic, PhD | Last updated:

SelfHacked has the strictest sourcing guidelines in the health industry and we almost exclusively link to medically peer-reviewed studies, usually on PubMed. We believe that the most accurate information is found directly in the scientific source.

We are dedicated to providing the most scientifically valid, unbiased, and comprehensive information on any given topic.

Our team comprises of trained MDs, PhDs, pharmacists, qualified scientists, and certified health and wellness specialists.

All of our content is written by scientists and people with a strong science background.

Our science team is put through the strictest vetting process in the health industry and we often reject applicants who have written articles for many of the largest health websites that are deemed trustworthy. Our science team must pass long technical science tests, difficult logical reasoning and reading comprehension tests. They are continually monitored by our internal peer-review process and if we see anyone making material science errors, we don't let them write for us again.

Our goal is to not have a single piece of inaccurate information on this website. If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please leave a comment or contact us at [email protected]

Note that each number in parentheses [1, 2, 3, etc.] is a clickable link to peer-reviewed scientific studies. A plus sign next to the number “[1+, 2+, etc...]” means that the information is found within the full scientific study rather than the abstract.

Health Effects of the Probiotic L. johnsonii

L. johnsonii is a probiotic that is especially good for fighting H. pylori infections. Learn about its other health benefits & safety.

What is Lactobacillus johnsonii?

Lactobacillus johnsonii is a lactic acid bacterium that resides in the human gastrointestinal tract where it aids in polysaccharide and protein digestion and also generates a variety of nutrients, including vitamins and short-chain fatty acids. L. johnsonii also plays a role in the fermentation and preservation of various food items.

Health Benefits of L. johnsonii

1) Combats H. pylori

Fermented milk containing L. johnsonii co-administered with antibiotics was shown to have a favorable effect on H. pylori gastritis [1].

L. johnsonii inhibits H. pylori colonization in children [2, 3]. and in asymptomatic volunteers [4].

During the early infection stages, administration of L. johnsonii can attenuate H. pylori-induced gastritis in mice [5].

Both live and heat-killed L. johnsonii inhibit the growth of H. pylori in mice, where they also suppress gastric acid secretion [6].

2) Improves Gut Microbiota

Fermented milk with L. johnsonii increased total Bifidobacteria and Lactobacilli and decreased lecithinase-positive Clostridium in women [7].

L. johnsonii intake increased the populations of C. histolyticum, Lactobacilli, and Bifidobacteria, and decreased those of F. prausnitzii in healthy volunteers [8].

3) May Improve Diabetes

L. johnsonii inhibited hyperglycemia reduced the elevation of blood glucose and glucagon levels in diabetic rats [9].

L. johnsonii delays or inhibits the onset of type 1 diabetes in diabetes-prone rats [10, 11].

L. johnsonii inhibits insulin resistance in mice [12].

4) May Lower Blood Pressure

L. johnsonii lowers blood pressure in rats [13].

5) May Be Beneficial in Liver Disease

L. johnsonii protects mice with non-alcoholic fatty liver disease (NAFLD) from liver steatosis and liver cell death [12].

6) Boosts Immunity

Fermented milk containing L. johnsonii suppressed infections in the elderly [14].

L. johnsonii helps recover nutritional status and systemic immune responses in aged mice [15].

L. johnsonii inhibits the growth of Helicobacter pylori, Escherichia coli, Salmonella Typhimurium, and Clostridium difficile in laboratory experiments [6].

7) Improves Allergies

The addition of L. johnsonii to levocetirizine improved perennial allergic rhinitis in children [16]

8) Protects the Skin

L. johnsonii significantly inhibited the development of UVA-induced skin lesions in clinical studies [17].

L. johnsonii suppresses exacerbation of dermatitis and scratching and reduces epidermal hyperplasia and infiltration of inflammatory cells in mice [18].

L. johnsonii administered in the weaning period inhibits atopic dermatitis-like lesions in mice after maturation, by modulating or accelerating the gut immune response [19].

9) May be Beneficial in Urogenital Infections

L. johnsonii inhibits G. vaginalis-induced vaginosis in mice [20].


  • Decreases IL-1β, IL-6 [20], IL-4 [21] and IL-8 [5].
  • Increases IL-10 [20].
  • Increases Th17 [11].
  • Increases COX2 [10, 20] and claudin [10].
  • Decreases TNFα [20, 12, 14], C-reactive protein [12] and iNOS [10, 20].
  • Inhibits NF-κB [20].
  • Decreases GPX1, GR, CAT [10], ACACA, FAS, and PPAR-γ [12].
  • Both increases [21] and decreases [10] IFN-γ.
  • Increases blood Hb, serum albumin [14], and blood phagocytic activity [14].
  • Increases IgA [22] and IgG [15] and decreases IgE [21].
  • Increases CD8(+) T cells [15].
  • Lowers CD86 [23].


Probiotics are generally considered safe but should be avoided in patients with organ failure, immunocompromised status, and dysfunctional gut barrier mechanisms.


This section contains a sponsored link, which means that we may receive a small percentage of profit from your purchase, while the price remains the same to you. The proceeds from your purchase support our research and work. Thank you for your support.

About the Author

Biljana Novkovic

Biljana Novkovic

Biljana received her PhD from Hokkaido University.
Before joining SelfHacked, she was a research scientist with extensive field and laboratory experience. She spent 4 years reviewing the scientific literature on supplements, lab tests and other areas of health sciences. She is passionate about releasing the most accurate science and health information available on topics, and she's meticulous when writing and reviewing articles to make sure the science is sound. She believes that SelfHacked has the best science that is also layperson-friendly on the web.

Click here to subscribe


1 Star2 Stars3 Stars4 Stars5 Stars
(2 votes, average: 5.00 out of 5)

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.