Constipation: What Actually Works?

Constipation is common, but it’s rarely as simple as “not enough fibre.” For many adults, bowel regularity is influenced by gut motility, the microbiome, hormones, and nervous system function. Here’s what the evidence actually shows helps.

Do Probiotics Help Constipation?

A large review of over 30 randomised controlled trials (2,800+ participants) found probiotics can:

• Increase stool frequency

• Improve overall constipation symptoms

• Not consistently improve stool consistency

• Show no clear effect on whole-gut transit time

Takeaway: Probiotics can help- but only certain strains. Not all probiotics are equal.

Probiotic Strains with the Best Evidence

The most studied strains for improving colonic transit include:

• Bifidobacterium animalis DN-173 010 (found in Activia yoghurt)

• Bifidobacterium lactis HN019 (available in many supplement brands)

HN019 has shown significant reductions in gut transit time, meaning stools move through the colon more efficiently.

Clinical tip: Always check the strain code, not just the species name.

Other Strains with Supportive Evidence

Additional strains with data supporting constipation relief include:

• Lactobacillus reuteri

• Bifidobacterium animalis ssp. lactis Bb12

• Multi-strain formulations (e.g. Bio-Kult-style blends)

Trial one strain at a time for around 4 weeks.

Food First: What to Try Before Supplements

Before reaching for probiotics or laxatives, optimise food:

• ½ cup yoghurt with live cultures or fermented milk with HN019

• 2 green kiwifruit daily

• 2 tbsp ground flaxseed

• 2-4 prunes per day

• 1-2 tbsp psyllium husk (with adequate hydration)

These foods work via fermentation, stool hydration, and gut motility- not just fibre bulk.

If Constipation Persists, Consider:

• Changing fibre type (PHGG is often better tolerated than psyllium)

• Magnesium citrate (with guidance)

• Further gut assessment, including microbiome testing

Avoid relying on stimulant laxatives as a first-line solution.

The Bottom Line

Constipation isn’t just about fibre. It’s influenced by the microbiome, gut movement, hormones, nervous system regulation, and overall diet quality. A targeted, personalised approach works best.