Can 'brown fat' explain the link between temperature and diabetes?

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Are rising global temperatures also increasing the incidence of diabetes? A new study from the Netherlands suggests there may be a link between warming global temperatures and higher rates of the disease, but not all experts are convinced. When researchers analyzed average global temperatures and incidence of type 2 diabetes, they found that a temperature increase of 1.8 degrees Fahrenheit (1 degree Celsius) was associated with 0.3 cases of diabetes per 1,000 people. In the United States, this equates to more than 100,000 new cases of type 2 diabetes each year, according to research published Monday (March 20) in the journal BMJ Open Diabetes Research & Care.

The new study may be interesting, but it only shows a link between rising temperatures and diabetes rates, said Dr. Christian Koch, a professor of endocrinology at the University of Mississippi Medical Center. Take part in this new study. Koch added that while both temperatures and diabetes rates are rising, there is "no causal relationship" between the two. "5 Ways Climate Change Can Affect Your Health."

Importantly, the study did not include two key factors: physical activity levels and indoor climate control — namely, air conditioning, " Science Is there a possible link? The study looked at the incidence of type 2 diabetes in 50 states, as well as Guam, Puerto Rico and the U.S. Virgin Islands from 1996 to 2013. Researchers also looked at the same years. Average temperature data for each state and region.

Overall, the researchers found, people were diagnosed with type 2 diabetes at higher rates in warmer years.

Data on global rates of type 2 diabetes were not available, the researchers noted. Instead, they used World Health Organization data on rates of high blood sugar, a factor associated with diabetes, which the researchers found to be the global average. Rates of hyperglycemia increased by an average of 0.2 percent for every 1.8 degrees Fahrenheit increase in temperature, the researchers wrote in the study. Overall, diabetes rates in the U.S. increased as global outdoor temperatures increased, the researchers wrote in the study. The incidence of hyperglycemia is increasing around the world. "Brown fat"

"The potential link between rising temperatures and diabetes lies in a type of fat called brown adipose tissue, or brown fat. [What is brown fat? The researchers wrote:

Brown fat is metabolically active; it breaks down smaller fat molecules to produce heat. Previous research has found that colder temperatures activate brown fat and may lead to modest weight loss, according to this study. Separately, a 2015 study published in the journal Nature Medicine In a small study, a team of researchers found that when people with type 2 diabetes were exposed to moderately cold temperatures for 10 days, their insulin sensitivity improved. (Reduced sensitivity to insulin, or insulin resistance, predisposes a person to type 2 diabetes.)

The researchers hypothesized that based on brown fat's possible effect on insulin, combined with the finding that low temperatures activate insulin, warmer temperatures Temperatures may have the opposite effect, i.e. they may be associated with reduced insulin sensitivity and increased type 2 diabetes. It's not that simple, however, Koch points out that most people spend most of their time exposed to indoor temperatures, so outdoor temperatures won't have such a dramatic effect.

In addition, he said, researchers found that rising temperatures had different effects on diabetes rates in two neighboring states: Diabetes rates dropped in Louisiana, while rates in Mississippi rise.

If temperature plays a role, fi