Eating lots of sugar has long been linked to increasing diabetes risk. Whether sugar causes diabetes is unclear, but evidence is mounting that too much of a sweet thing can trigger the disease.
If you’re overweight, your risk of developing diabetes goes up, and sugar can certainly pack on the pounds. The American Diabetes Association recommends that people should limit their intake of sugar-sweetened beverages to help prevent the disease. New research raises more concerns about the role sugar may play in causing diabetes.
Sanjay Basu, MD, an assistant professor of medicine at the Stanford Prevention Research Center in Palo Alto, California, headed up a study looking at diabetes rates in relation to sugar availability in 175 countries over the course of 10 years.
Dr. Basu and his research team found that the incidence of type 2 diabetes rose by 1 percent for every additional 150 calories of sugar available per person. There are 136 calories in a 12-ounce can of regular cola, according to the Centers for Disease Control and Prevention.
“Our results show that sugar availability is a significant statistical determinant of diabetes prevalence rates worldwide,” the authors said.
Nearly one in 10 people worldwide has diabetes, according to the World Health Organization. Diabetes prevalence rates rose 27 percent on average from 2000 to 2010, with just over one-fourth of the increase explained by a rise in sugar availability in this model.
Diabetes—Not Just for the Obese
While previous research has tied diabetes to obesity, this study highlighted that diabetes could be brought on by sugar consumption, independent of obesity. In other words, obesity doesn’t always cause diabetes, and the disease strikes those with normal weight as well as those who are overweight.
Investigators reported that in some countries, such as the Philippines, Romania, Sri Lanka, Georgia and Bangladesh, sugar availability rose by over 20 percent during the study period and diabetes rates were high, but obesity rates were low.
While about 20 percent of obese individuals appeared to have normal insulin regulation, normal metabolic indices (no indication of diabetes) and normal longevity, up to 40 percent of normal weight people in some populations developed aspects of the metabolic syndrome, according to this research.
The authors wrote that most of the worldwide rise in type 2 diabetes was linked to the metabolic syndrome.
A Matter of Metabolism
Metabolic syndrome is the name for a group of risk factors that raises your risk for heart disease and other health problems, such as diabetes and stroke. The term "metabolic" refers to the biochemical processes involved in the body's normal functioning.
The National Heart, Lung, and Blood Institute says that a person with metabolic syndrome is five times more likely to develop diabetes than someone who doesn't have metabolic syndrome. The organization lists five conditions that are considered metabolic risk factors. You must have at least three metabolic risk factors to be diagnosed with metabolic syndrome.
- A large waistline. Abdominal obesity or “having an apple shape” means you have excess fat in the stomach area.
- A high triglyceride level (or you’re on medicine to treat high triglycerides). Triglycerides are a type of fat found in the blood.
- A low HDL cholesterol level (or you’re on medicine to treat low HDL cholesterol). HDL cholesterol (the “good” cholesterol) helps remove LDL cholesterol (the “bad” cholesterol) from your arteries.
- High blood pressure (or you're on medicine to treat high blood pressure). Blood pressure is the force of blood pushing against the walls of your arteries as your heart pumps blood. If this pressure rises and stays high over time, it can damage your heart and lead to plaque buildup.
- High fasting blood sugar (or you're on medicine to treat high blood sugar). Mildly high blood sugar may be an early sign of diabetes.
Insulin resistance may also increase your risk of having metabolic syndrome. Insulin is a hormone that helps move blood sugar into cells where it's used for energy. When you have this condition, however, the body cannot use its insulin properly.
Genetics (ethnicity and family history) and older age are other factors that may play a role in metabolic syndrome.
Over a quarter of all people age 65 and older have diabetes, according to the American Diabetes Association.
Dr. Basu said in a statement to UCHealth, “We’re not diminishing the importance of obesity at all, but these data suggest that at a population level there are additional factors that contribute to diabetes risk besides obesity and total calorie intake, and that sugar appears to play a prominent role.”
All Calories Are Not Created Equal
The research indicates that all calories are not the same, and calories from overconsumption of sugar brings on metabolic syndrome.
The scientists observed that sugars added to processed food, particularly monosaccharide fructose, can contribute to obesity, but also appear to have properties that increase diabetes risk independently from obesity. Sugary foods have been significantly associated with the development of insulin resistance in laboratory-based studies.
The study found no significant difference in results between those countries that rely more heavily on high-fructose corn syrup and those that rely primarily on cane sugar.
For diabetes patients, concern over eating sugar has also brought fruit into question because of its sugar content. A study in the March issue of Nutrition Journal, however, found that diabetes patients did not appear to benefit by eating less fruit.
Researchers in Denmark reported that overweight patients with newly diagnosed type 2 diabetes may be advised to eat less fruit as part of standard medical nutrition therapy.
In this study, when patients with diabetes decreased the amount of fruit they ate, it had no effect on HbA1c (a measure of blood sugar levels), weight loss or waist circumference. Based on these results, investigators recommended that patients with type 2 diabetes do not restrict their fruit consumption.
The study led by Dr. Sanjay Basu was published in February in PLoS One and the study in Nutrition Journal was published in March.