Review · Nutrients · 2024Conflicts declared

Lactose intolerance and precision nutrition approaches

What it found

About 70% of adults worldwide cannot fully digest lactose, and the authors say a personalised approach based on genes, gut bacteria and individual tolerance is better than one rule for everyone.

What they found

Studies in people

How common

Around 70% of adults across different countries cannot fully digest lactose. This is mainly because they make less lactase in the small intestine.

Symptoms

People with lactose intolerance get bloating, gas, diarrhea or indigestion after taking in lactose. Some also get symptoms outside the gut, depending on how much lactose they eat and how much lactase they have.

Genes and lactase

Variants near the LCT gene affect whether someone keeps making lactase as an adult. The -13910:C>T variant is the most widespread in parts of Europe, while other variants are found in Africa and the Middle East.

Genetic test errors

A report on direct-to-consumer genetic tests for lactose intolerance found 40% false positives among the genetic results. Self-reported lactose intolerance and genetic test results are often unrelated.

Studies in people and animals

Gut bacteria and lactose

More colonic bacteria able to ferment lactose seems linked to fewer lactose intolerance symptoms like diarrhea. Prebiotics such as galacto-oligosaccharides feed these bacteria and improve lactose digestion and tolerance.

Probiotics for symptoms

Some probiotics, such as Lactobacillus acidophilus found in yogurt, have beta-galactosidase activity that can ease lactose intolerance symptoms. Combining several strains with this activity increases the effect.

Other findings

Lactose and lactase

Lactose is a sugar made of glucose and galactose. The body needs the enzyme lactase to split it so it can be absorbed from the small intestine.

What the authors conclude

“Here, we report the opinion of the scientific community proposing to replace the "one size fits all" approach with tailor-made nutrition programs, designed by integrating nutrigenomic data together with clinical parameters and microbiota profiles, taking into account the individual lactose tolerance threshold and needs in terms of specific nutrients intake.”
Pratelli G, Tamburini B, Badami GD, et al, 2024

Also in their conclusions

  • They propose replacing the "one size fits all" approach with tailor-made nutrition programs, designed by integrating nutrigenomic data together with clinical parameters and microbiota profiles.
  • They say this customized approach could help LI patients to improve their quality of life, overcoming depression or anxiety often resulting from the individual perception of this condition as different from a normal state.
  • They advise that the right LI approach includes a lactose-free or low-lactose diet, colon microbiome adaptation, using specific probiotic strains with beta-galactosidase enzymatic activity, and oral lactase enzyme replacement.

How it was done

The authors say people with lactose intolerance often cut out milk and miss out on its proteins and calcium, and that a wrong diagnosis or treatment can lead to unnecessary dietary restrictions or avoidable reactions, especially in infants and young children.

What it can’t tell you

  • This is a review, so it cannot show cause and effect for any single finding.
  • Some findings come from animal or lab studies, which cannot show what happens in people.
  • The paper does not report a single trial testing whether precision nutrition works better than standard advice for lactose intolerance.

The paper

Title
Cow's Milk: A Benefit for Human Health? Omics Tools and Precision Nutrition for Lactose Intolerance Management
Type
ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
Evidence
Studies in people · animals · lab
Summarised from
Full text
Cite
Pratelli G, Tamburini B, Badami GD, et al (2024). Cow's Milk: A Benefit for Human Health? Omics Tools and Precision Nutrition for Lactose Intolerance Management. Nutrients. doi:10.3390/nu16020320Free full textPubMed 38276558DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error