Frequent use of laxatives does not increase your risk of dementia · Health and science

Where does this news come from?

An international group of researchers investigated the link between the use of laxatives and dementia (1). Taking laxatives frequently could disrupt the composition of your gut bacteria. According to the scientists, this could lead to dementia. They used data from a large cohort study, a type of observational study (UK Biobank Study):

• Between 2006 and 2020, researchers followed up a group of 502,229 individuals.
  • They checked at the start of the study how often the participants used laxatives.
  • During the further follow-up, they registered who developed dementia.

• Of all participants, only 18,235 (3.6%) people regularly used laxatives, a very small minority.

• received during the follow-up 218 (1.3%) participants who took laxatives experienced dementia. In the much larger group of people who no laxatives names developed only 1,969 (0.4%) participants had dementia.

• Taking confounding factors into account, risk of dementia increased by 51% in the group the laxatives used.

The researchers conclude that individuals who regular laxatives use, especially multiple typesAn higher risk of dementia to have.

Bron

(1) Yang Z, Wei C, Li X, et al. Association Between Regular Laxative Use and Incident Dementia in UK Biobank Participants. Neurology. 2023 Feb 22:10.1212/WNL.0000000000207081.

How should you interpret this news?

The researchers’ conclusion is incorrect, because you cannot establish a cause-and-effect relationship on the basis of an observational study:

• There was certainly a link between laxatives and dementia, but many factors can explain that connection:
  • The small group that used a lot of laxatives averaged:
    • older;
    • less active;
    • heavier;
    • more often depressed;
    • more frequent diabetes patient;
    • smoker more often.
  • These are all factors that can play a role in the development of dementia.

• The group that less dementia developed, also drank significantly more alcohol. That’s remarkable.
  • We just took a closer look at a study that showed that light to moderate alcohol consumption may protect against dementia (2).

• The researchers describe how the intestinal bacteria (gut flora) could play a role in the development of dementia.
  • However, other recent research contradicts that hypothesis (3).
  • There were too no data on dietary fiber intakewhich can affect your intestinal flora.
  • The study also did not examine whether the intestinal flora in users of laxatives had changed.

• During the large cohort study probed the researchers only at the start of the study into laxative use.
  • So they assumed that the participants would continue to take the same amount of laxatives for the next ten years. But that’s not certain.

• The fact that 1.3% of laxative users developed dementia also means that 98.7% did not develop dementia.

Conclusion

An observational study finds that individuals who take many (types of) laxatives are more likely to develop dementia. However, that is not necessarily a causal relationship. In the very small group of participants who frequently used laxatives, many other risk factors were involved that increase the risk of dementia, such as an unhealthy lifestyle. Thus, laxatives have not been shown to increase the risk of dementia.

References

(2) Krüger JF, Hillesheim E, Pereira ACSN, Camargo CQ, Rabito EI. Probiotics for dementia: a systematic review and meta-analysis of randomized controlled trials. Nutr Rev. 2021 Jan 9;79(2):160-170.