Doc: Diabetes’ underlying cause is insulin resistance
Dear Dr. Roach: I was under the impression that fat was the major cause of Type 2 diabetes. When fat clogs the arteries, it does not allow sugar, from any source (table sugar, potato or Twinkie), to pass through the clogged arteries, which in turn causes the insulin levels to be abnormally heightened. Is this right? I saw nothing of this in your article.
Dear R.A.S.: In Type 2 diabetes, the underlying cause is a resistance to insulin and a decreased ability to move sugar into cells. The exact cause for insulin resistance is not yet worked out. The resistance to insulin causes the pancreas to release even more insulin, leading to high insulin levels, which affects fat metabolism, leading to a propensity to gain weight. However, the blockage in arteries from fat deposits is more likely a result of diabetes, and not its cause. Also, because of the resistance to insulin, blood sugar is higher than normal, especially after eating, which also tends to damage blood vessels, particularly small ones.
A diet low in simple carbohydrates, especially simple sugars, is critically important for people with Type 2 diabetes. Healthy fats, from nuts or olive oil, for example, slow absorption of sugar and tend to improve blood sugar control, along with good sources of protein. Carbohydrates from plant sources are absorbed much more slowly, and should be the major source of carbohydrate calories.
Dear Dr. Roach: I’m a 75-year-old male. A recent endoscopy showed I have Barrett’s esophagus with no dysplasia. I was told to take omeprazole every day to control acid reflux. My concern is that I was not told of anything I might do to prevent Barrett’s esophagus from progressing to cancer. From what I read online, it appears that omeprazole has not been found to halt this progression. Two studies for which I found abstracts report that aspirin might work, but these did not specify whether the aspirin was 81 mg or 325 mg. Please help me to understand what I can do here.
Dear J.S.: Barrett’s esophagus is a complication of long-term reflux of stomach acid into the esophagus, and it confers a 30-times-higher risk of developing cancer of the esophagus. However, the absolute risk of developing esophageal cancer is still small: The best estimate is that someone with Barrett’s esophagus without dysplasia (early signs of transformation to cancer) would have about a 5 percent chance in 20 years.
Aspirin does seem to reduce that risk by about 30 percent. To put that another way, your chance of NOT developing cancer in the next 20 years is about 95 percent, and it would be expected to be about 97 percent if you took aspirin. The study that showed this looked at all people who took aspirin (usually 81 mg daily or 325 mg every other day). Long-term aspirin has its own risks and shouldn’t be taken without consultation with your doctor.
One recent study suggested that the combination of aspirin (or an NSAID) with a statin decreased the risk of esophageal cancer by nearly 80 percent. A large trial looking at the preventive effect of aspirin is underway in the U.K.
Email questions to ToYourGoodHealth @med.cornell.edu.