While it might run counter to conventional wisdom, if you are lactose intolerant, you might want to drink some milk every day to ward off diabetes. So says a new study that looked at a genetic variant involved in the effect.
The link between milk drinking and diabetes has been examined before with mixed results. Some studies showed a relationship, while others didn't. And, even when a positive effect on the lowering of type II diabetes risk was established, it was only seen in the consumption of low-fat dairy products.
Thinking this variation might be due to genetic variables, a team of 20 researchers from a variety of institutions in the US and China carried out a review of about 12,000 Hispanic adults who participated in the Hispanic Community Health Study/Study of Latinos. This study began in 2006 and has tracked the health data of over 16,000 Hispanic individuals over the years.
To look for a link that might explain the mixed results found between dairy and diabetes, the researchers carried out what's known as a genome-wide association study, or GWAS, which simply looks for genetic explanations for certain traits. They found that people who had a genetic variant that made people lactose intolerant – also called being lactase non-persistent (LNP) – showed a 30% lower risk of developing type 2 diabetes when they regularly drank milk. They backed up these findings with an analysis of UK Biobank data, where an analysis of 160,000 people also showed the link.
Of course, that calls into question the risk/reward equation as it applies to someone's health. Is drinking a substance your body can't digest well worth lowering the risk of a disease you might never get in the first place? It depends on the individual, says Lonneke Janssen Duijghuijsen, a nutrition and health researcher at Wageningen University in the Netherlands, who wasn't involved in the research.
“Lactase non-persistence does not necessarily preclude the ability to consume some amount of lactose," he said in a statement. "Research has shown that many lactase non-persistent individuals can still consume up to 12 grams of lactose per day, comparable to the amount in a large glass of milk, without suffering from intolerance symptoms. The ability to tolerate lactose varies among individuals; some can consume more than 12 grams without issues, while others may experience symptoms with lower doses.”
Duijghuijsen led another study that was published in December showing that LNP individuals who drank milk had changes in their gut microbiome based on the way in which lactose was broken down in their intestines. Changes in the microbiome could therefore account for the metabolic effects seen in the new study. Still, he cautions that more research is needed to firmly establish causation purely between milk drinking in LNP individuals and their risk for developing diabetes, and to rule out other factors that might be at play.
“The study does not explicitly provide dietary recommendations but rather highlights potential effects of milk consumption by a specific population on gut microbiota and its metabolites and the potential relation with a specific health outcome," he said. "They are transparent that it is an observational population-based epidemiological study unable to make causal inferences."
The research has been published in the journal Nature Metabolism.
Source: Medical Xpress