As if a diagnosis of type 1 diabetes—the inherited type—wasn’t bad enough, it comes with the knowledge that your risk of heart disease will be 10 times higher than that of the general population. Now comes news that there may be a way to manage that risk: A small preliminary clinical trial has found that one additional injection of insulin three hours after higher-fat meals may protect people with type 1 diabetes from heart troubles.
In order to control blood sugar, people with type 1 diabetes typically inject insulin after mealtimes, basing their dosage on the amount of carbs in their food. However, fat—which insulin also helps process—slows down digestion. That means sugars and fats can hit the bloodstream after insulin levels have diminished. Without insulin, levels of sugars and fats soar, damaging blood vessels and increasing inflammation—the very conditions that boost the risk of heart disease.
The trial, published in Diabetes and Vascular Disease Research, involved type 1 diabetics who were given meals made up of identical amounts of carbohydrate and protein; the only difference was that some of the meals were high in fat, while others were low. After downing a low-fat meal, the participants injected insulin as usual. Following a high-fat meal they did the same, but then, three hours later, they injected another dose of fast-acting insulin at one-third the strength of the post-meal shot.
As the researchers expected, one insulin injection was enough to normalize blood levels after the low-fat meal. But the high-fat meal was a different story: Upon analyzing the men’s blood samples—taken every half hour for six hours after the meal—the researchers found that blood levels of sugar, fat, and inflammation markers remained elevated. The extra insulin injection was necessary to get everything back to normal.
Of the findings, co-author of the study, Dr. Matthew Campbell from Leeds Beckett University, said in a press release: “Many people with type 1 diabetes struggle to regulate their blood sugar levels around mealtimes, because the fat content in their food is metabolized after their standard insulin injection has lost its potency or has left their blood.” Campbell noted the need for advice to be given to people with type 1 diabetes to be updated, and that the researchers’ findings should be included.
According to co-author Dr Daniel West, of Newcastle University, while improving sugar and fat levels in the blood after eating is vital for long-term health of the heart and blood vessels, “calculating insulin injection dose based on carbohydrates alone is clearly too simplistic, as most people eat meals that include fat and protein too.”
Registered dietitian Nicole Osinga feels it may be too soon to act on this small study. “It is true that a higher fat meal takes longer to metabolize, leading to a later spike in blood sugar. This is where more insulin after a meal is eaten could make sense,” she said. “However I’m afraid this can be potentially confusing for the public. People with type 1 diabetes have a lot to keep track of and calculate already, and there may be an increased burden to calculate the fat grams and carbohydrate grams and dose insulin appropriately.” Osinga worries that this can really take the pleasure out of eating as well.
The study’s authors now intend to begin a larger scale trial, which will perhaps bring more weight for or against its claims that an additional injection at a smaller dose is beneficial.