Myth or fact? Eating too much sugar causes diabetes

Even though diabetes is a common disease, there is a lot of misinformation about it. No one knows this better than endocrinologist Mary Crowell, MD at the Endocrine Center of Cape Cod at Cape Cod Hospital. She spends about half of her time with patients with diabetes and over the past 13 years she has heard a lot of misinformation.

With that in mind, Dr. Crowell gave a talk at World Diabetes Day at the YMCA Cape Cod in West Barnstable recently, called “Diabetes, Fact or Fiction.” She discussed some of the most common truths and misconceptions:

Diabetes is a group of diseases that result in too much sugar in the blood. True.

Diabetes is a group of diseases associated with carbohydrate metabolism, Dr. Crowell explained. Carbohydrates are the sugars and starches in food that our bodies break down into simple sugars to use for fuel. The way the body absorbs these sugars is with the hormone insulin.

“Our pancreas makes insulin and insulin opens the gate in our cells to allow the sugar that’s in our blood to go into our cells,” she said. “In all forms of diabetes there is a problem getting that sugar from the blood into the cells.”

Type 1 diabetes is an autoimmune disease where the immune system attacks the pancreas and causes it to be unable to make insulin. Type 2 diabetes is a resistance to the effects of the body’s insulin.

Diabetes is caused by eating too much sugar. False.

Both type 1 and type 2 diabetes have a genetic component, but there also needs to be a trigger that takes that genetic risk and turns it into diabetes. With type 1 diabetes, researchers don’t know what the trigger is. There are theories that cold weather, not being breastfed long enough or introducing solid food too early might be triggers, but recent research is focusing on the idea that it might be caused by a virus, according to Dr. Crowell.

With type 2 diabetes, the trigger is lifestyle, including obesity, not eating a healthy diet and not getting enough physical exercise.

Type 1 diabetes runs more strongly in families than type 2. False

In the United States, the risk of developing type 1 diabetes is one in 100, according to Dr. Crowell. If you have an immediate family member who has type 1 diabetes, the risk becomes one in 10. If you have an identical twin with type 1 diabetes, the risk is one in two or 50 percent.

“In the U.S., the risk of type 2 diabetes is about one in 10,” she said. “It’s a lot more common that type 1 diabetes.”

If your parent has type 2 diabetes, your risk is somewhere between one in three and one in seven. It is lower if your parent was diagnosed later in life, but it is higher if your mother has diabetes or if your parent is thin with diabetes. If both parents have diabetes, you have about a 50 percent chance of developing diabetes yourself. If you have an identical twin who has type 2 diabetes, your risk of developing it yourself is 75 percent more.

Diabetes is a common disease. True

In 2014 there were about 320 million people in this country and Dr. Crowell said that researchers think that around 30 million of them have diabetes. That is about 9 to 10 percent of the population.

“Here’s a scary fact,” she said. “Current estimates state that around 86 million more have pre-diabetes, so about 37 percent of the U.S. population have diabetes or pre-diabetes.”

Since 1980, the incidence of diabetes has increased by 177 percent in men and 114 percent in women. But the good news is that since 2010, these rates seem to have leveled off.

Diabetes is not that serious. False

Diabetes causes more deaths each year than breast cancer and HIV combined, Dr. Crowell said. If you have diabetes, your risk of a heart disease almost doubles and your risk of stroke goes up about by one and a half. It can cause nerve damage, amputation and kidney damage or failure.

People with diabetes need to follow a special diet. False

“I’m going to argue false,” Dr. Crowell said. “I’m going to argue that people with diabetes simply need to follow the same healthy meal plan that everybody should be following.”

This diet should be lower in saturated trans fats that you get from animals and higher in healthy fats. You should eat lean proteins like chicken and fish. Eat a lot of non-starchy vegetables like peppers, cauliflower and broccoli and stay away from corn and peas. And you do this all in moderation.

People with diabetes can’t eat starches like bread or pasta and can’t eat dessert. False.

When Dr. Crowell talks to her patients about carbs, she explains that not all carbs are equal.

Complex carbohydrates like those found in whole grains are hard to digest so your blood sugars are not going to go up as high.

Portion size is important and people with diabetes should try to restrict their carbs to 30 to 60 grams per meal.

“Think of your carbohydrates as a savings bank,” she said. “You can only use so many carbs. If you’re going to have that treat, plan the rest of your meal around it.”

Fruit is a healthy food so it’s okay to eat as much fruit as you like. False.

Fruit has a lot of healthy fiber, but it also has a lot of sugar. If you are keeping your carbs between 30 and 60 grams per meal, one apple or banana is your whole meal. Three-quarters of a cup of grapes have 20 grams of carbohydrates. Fruit doesn’t need to be eliminated, but it does need to be limited.

If I take my diabetes medication I can eat whatever I want. False

We have more options to control diabetes than ever, but all of the current medications are only going to lower your blood sugar by so much. People with diabetes need to budget their carbs, avoid drinking too many sugary beverages and eat a healthy diet in moderation, according to Dr. Crowell

Once you start diabetes medication you can never stop. False

Many people need to stay on medication for diabetes for life, but some are able to stop their medications with lifestyle changes like weight loss and increased physical activity. Some patients are even able to stop taking insulin, she said.

You can delay or even prevent diabetes from happening. True

While you can’t change your genetic makeup, your ethnicity or your age, you can change your weight, diet and physical activity. Since high blood pressure and high cholesterol increases risk, you can keep those factors under control with medication if necessary.

Dr. Crowell pointed to the Diabetes Prevention Program, a major clinical research study published in the New England Journal of Medicine in 2002 to see whether 3,234 participants people with pre-diabetes could prevent or delay the onset of Type 2 diabetes with lifestyle or medication. People in the lifestyle intervention group reduced their risk of developing diabetes over three years by 58 percent by just losing just 7 percent of their body weight. Lifestyle intervention was particularly helpful for those over the age of 60, reducing their risk by 71 percent.

Those who took the medication metformin reduced their risk by 31 percent and it was least effective for those over the age of 45.

“People who changed their lifestyle were twice as successful,” Dr. Crowell said. “That is a powerful, powerful fact. You absolutely can change your course.”