Хоолны дарааллыг өөрчлөх нь цусан дахь сахарын хэмжээг хянахад тусалж болзошгүй

One of the core challenges in diabetes is controlling your blood sugar after eating, particularly when carbohydrates are involved.

But new findings give further evidence that it’s not just what you eat that matters when it comes to controlling blood glucose – when you eat is also an important factor.

In a study published in Diabetes, researchers found that mice fed olive oil before consuming glucose saw a reduced increase in blood sugar afterward.

“Our findings suggest that the order in which nutrients reach the gut can engage a coordinated hormone-nerve response that changes how quickly the stomach delivers glucose to the intestine,” says endocrinologist Daisuke Yabe from Kyoto University.

While the new findings have only been demonstrated in mice for now, it’s not the first time we’ve seen evidence that the order foods are eaten can affect how blood sugar levels respond after a meal.

Meal-sequencing is an emerging dietary approach to help treat and manage diabetes and obesity, with evidence showing that eating vegetables or foods rich in protein or in fat prior to eating carbohydrates helps to keep people’s blood sugar lower.

It’s thought that this could be due to certain nutrients slowing the process of gastric emptying, which means food moves more slowly into the small intestine, delaying the absorption of glucose into the bloodstream.

Another possibility is that eating some foods before carbs may induce the secretion of glucagon-like peptide-1 (GLP-1) – the appetite-suppressing and insulin-boosting hormone mimicked by drugs like Ozempic.

To explore these mechanisms further, Yabe’s team conducted an experiment with mice, evaluating three separate conditions after an overnight fast.

In one test, mice were given olive oil 15 minutes before being given glucose. Another group received glucose first, then olive oil. A third group of mice served as controls, consuming water followed by glucose.

Blood tests after the feeding experiment showed that mice fed olive oil before the glucose had significantly lower blood glucose immediately after the meal, with marked reductions at the 15- and 30-minute marks compared to the other mice, although the effects appeared to diminish by 60 minutes.

The mice fed olive oil first also showed slower gastric emptying and had higher levels of the hormones glucagon, glucose-dependent insulinotropic polypeptide (GIP), and GLP-1 in their blood – suggesting a range of hormonal responses that may help slow gastric emptying and limit blood sugar spikes.

The researchers tested other fats in addition to olive oil, including flaxseed oil, lard, coconut oil, and fish oil. Olive oil generally performed the best in terms of controlling blood sugar, although flaxseed oil and lard produced similar results in some measures.

In separate experiments using mouse models of diabetes, pre-loaded olive oil offered similar benefits to blood sugar and gastric emptying, suggesting the mechanism operates even when the body’s ability to produce insulin is substantially reduced.

In other tests using drugs and genetically engineered mice, the researchers blocked the animals’ glucagon and GLP-1 signaling. They found that if one of these pathways was disrupted, olive oil still had beneficial effects, but if both pathways were blocked, the blood sugar reduction was weakened or lost, and the effects to slow gastric emptying vanished.

Similarly, in a final experiment, the researchers found that if they surgically disrupted vagus nerve signaling in mice, olive oil’s ability to mitigate blood sugar increases and slow gastric emptying was weakened or no longer detectable, even though the animals’ hormonal responses remained intact.

Taken together, it looks like olive oil’s benefits to control blood sugar involve both hormones and neural pathways, the team thinks.

“The effect appears to involve an integrated endocrine-neural response rather than a single hormone,” the researchers write.

“These observations suggest that early nutrient sensing activates coordinated endocrine responses that contribute to slowing gastric emptying and limiting glucose excursions.”

Given that olive oil doesn’t show the same benefits if it’s consumed after glucose, the order of the nutrients is a controlling factor, the study authors say.

It’s possible that if glucose is eaten first, its rapid absorption into the bloodstream may suppress the responsiveness of pancreatic alpha cells, impairing their ability to release glucagon in response to fatty acids. By contrast, consuming olive oil first may activate fatty acid-sensing mechanisms before blood glucose levels rise substantially.

There’s still a lot we don’t fully know about this mechanism, and it’s worth reiterating that these olive oil effects have so far only been shown in mice, with no guarantee we’d see the same benefits in human patients.

But the findings highlight a common ingredient that researchers might easily be able to test in people in future studies, and give us some new clues toward a better understanding of the ways meal sequencing may work.

“Our group has long been interested in practical dietary approaches that people can continue in everyday life,” Yabe says.

“Meal-sequencing is appealing because it merely changes how a meal is eaten rather than requiring people to avoid entire food groups.”

The findings are reported in Diabetes.