An analysis on the positive effects of exercise on blood sugar levels in people with Type 2 diabetes shows that while all exercise helps, certain activities – and their timing – are extremely good for people’s health.

The study, published in The American Journal of Medicine, provides a comprehensive but straightforward summary of the benefits of exercise on controlling blood glucose levels in people with Type 2 diabetes.

“The challenge with this is that most, if not all, people know exercise is good for them but they don’t know the best approach,” said Steven Malin, an associate professor in the Department of Kinesiology and Health at the Rutgers School of Arts and Sciences and an author of the study. “We targeted this issue by focusing on a few key parameters: the utility of aerobics versus weightlifting, the time of day that is optimal for exercise, whether to exercise before or after meals and whether we have to lose weight to get benefits or not.”

As part of the analysis, researchers sifted through dozens of studies and extracted common conclusions. Some of the key findings include:

• Habitual aerobic exercise: Physical activity, such as cycling, swimming and walking, that increases the heart rate and the body’s use of oxygen helps manage blood glucose.
• Resistance exercise: Working muscles using an opposing force such as dumbbells, resistance bands or a person’s own body weight benefits insulin sensitivity in those with Type 2 diabetes.
• Movement throughout the day by breaking up sitting time benefits blood glucose control and insulin levels.
• Performing exercise later in the day can result in better control of blood sugar levels as well as improve insulin sensitivity.

“In short, any movement is good and more is generally better,” Malin said. “The combination of aerobic exercise and weightlifting is likely better than either alone. Exercise in the afternoon might work better than exercise in the morning for glucose control, and exercise after a meal may help slightly more than before a meal. And, you don’t have to lose weight to see the benefits of exercise. That is because exercise can lower body fat and increase muscle mass.”

More than 37 million Americans have diabetes, and between 90 and 95 percent have Type 2 diabetes, according to the U.S. Centers for Disease Control and Prevention. People with Type 2 diabetes are insulin resistant, meaning that their cells don’t respond normally to insulin, a hormone that controls the level of sugar, or glucose, in the blood. High blood sugar is damaging to the body and can cause serious health issues.

While insulin resistance is harmful, scientists believe increased insulin sensitivity is beneficial. High insulin sensitivity allows the cells of the body to use blood glucose more effectively, reducing blood sugar.

Malin researches insulin sensitivity and teaches kinesiology, the study of human movement. He and several other faculty members at Rutgers support the concept of “exercise as medicine.” The idea, which is supported by the American College of Sports Medicine and is increasingly being borne out by research, is that exercise can be considered a first-line therapy.

“I’m one of those individuals who subscribes to that notion, and in that way, I think of exercise as a drug,” Malin said.

Malin and colleagues authored the study to offer the medical community up-to-date practical advice for their patients.

“Together, this idea of exercise timing and type is important because it helps medical professionals more accurately recommend exercise prescriptions to combat high blood glucose,” Malin said.

More than half a billion people are living with diabetes worldwide, affecting men, women, and children of all ages in every country, and that number is projected to more than double to 1.3 billion people in the next 30 years, with every country seeing an increase, as published today in The Lancet.

The latest and most comprehensive calculations show the current global prevalence rate is 6.1%, making diabetes one of the top 10 leading causes of death and disability. At the super-region level, the highest rate is 9.3% in North Africa and the Middle East, and that number is projected to jump to 16.8% by 2050. The rate in Latin America and the Caribbean is projected to increase to 11.3%.

Diabetes was especially evident in people 65 and older in every country and recorded a prevalence rate of more than 20% for that demographic worldwide. The highest rate was 24.4% for those between ages 75 and 79. Examining the data by super-region, North Africa and the Middle East had the highest rate at 39.4% in this age group, while Central Europe, Eastern Europe, and Central Asia had the lowest rate at 19.8%.

Almost all global cases (96%) are type 2 diabetes (T2D); all 16 risk factors studied were associated with T2D. High body mass index (BMI) was the primary risk for T2D – accounting for 52.2% of T2D disability and mortality – followed by dietary risks, environmental/occupational risks, tobacco use, low physical activity, and alcohol use.

“The rapid rate at which diabetes is growing is not only alarming but also challenging for every health system in the world, especially given how the disease also increases the risk for ischemic heart disease and stroke,” said Dr. Liane Ong, lead author and Lead Research Scientist at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington’s School of Medicine. “While the general public might believe that T2D is simply associated with obesity, lack of exercise, and a poor diet, preventing and controlling diabetes is quite complex due to a number of factors. That includes someone’s genetics, as well as logistical, social, and financial barriers within a country’s structural system, especially in low- and middle-income countries.”

“Some people might be quick to focus on one or a few risk factors, but that approach doesn’t take into account the conditions in which people are born and live that create disparities worldwide,” said Lauryn Stafford, second author and Post-Bachelor Fellow at IHME. “Those inequities ultimately impact people’s access to screening and treatment and the availability of health services. That’s precisely why we need a more complete picture of how diabetes has been impacting populations at a granular level.”

Using the Global Burden of Disease (GBD) 2021 study, researchers examined the prevalence, morbidity, and mortality of diabetes for 204 countries and territories by age and sex between 1990 and 2021 and forecasted diabetes prevalence to 2050. They also provided estimates of type 1 diabetes (T1D) and type 2 diabetes (T2D) and quantified the proportion of T2D burden attributable to 16 risk factors. The study team included researchers from IHME and GBD 2021 collaborators from around the world.

Fewer than six hours or more than 10 hours of sleep, and poor quality of sleep are associated with a greater risk for diabetes, according to research being presented Thursday at ENDO 2023, the Endocrine Society’s annual meeting in Chicago, Ill.

Poor sleep quantity and quality, and its impact on the risk for diabetes or obesity has been previously studied. However, this study sought to explore the longitudinal effects.

“Most previous studies did not examine changes in various glycometabolic parameters, like over 14 years. The pattern of changes in various glycemic parameters may provide clues to the mechanism underlying the association between sleep duration and incident diabetes mellitus,” said Wonjin Kim,  M.D., Ph.D., of CHA Gangnam Medical Center and associate professor at CHA University School of Medicine in Seoul, South Korea.

Kim and colleagues collected data from 8,816 of 10,030 healthy participants of the ongoing Korean Genome and Epidemiology Study (KoGES)-Ansung and Ansan Cohort Study. They identified diabetes cases and sleep duration and quality. Sleep duration was categorized into four groups: <6, 6-7, 8-9, or 9 hours per day. Sleep quality was measured among those with a sleep duration of <10 hours per day.

During the 14-year follow-up period, 18% (1630/8816) were diagnosed with diabetes. The researchers observed a U-shaped relationship between sleep duration and incident diabetes, with the greatest risk when sleep duration was ≥10 hours per day. During the study, this group also showed decreased insulin glycogenic index, which is a marker of insulin secretory function. The risk for incident diabetes increased among study participants who slept <10 hours per day when their Epworth Sleepiness Scale (ESS) score was >10.

“Even if sleep duration is less than 10 hours, the likelihood of developing diabetes is greater when quality of sleep decreases,” Kim said.

Early time-restricted feeding (eTRF) improves glycemia and inflammatory markers even in the absence of weight loss. CREDIT NYU Langone Health

Eating more of one’s daily calories earlier in the day may counter weight gain, improve blood sugar fluctuations, and reduce the time that blood sugar is above normal levels, a new study suggests.

“This type of feeding, through its effect on blood sugar, may prevent those with prediabetes or obesity from progressing to type 2 diabetes,” said study lead author Joanne H. Bruno, MD, PhD, an endocrinology fellow at NYU Langone Health.

Presented at the Endocrine Society’s annual meeting on June 15, the new report evaluated early time-restricted feeding (eTRF), which involves restricting calories to the first eight hours of the day. Previous studies have found this form of intermittent fasting may improve cardiometabolic health and blood sugar levels. However, the team wanted to determine whether these improvements are related to weight loss or the fasting strategy.

Led by researchers at NYU Grossman School of Medicine, the work is the first to evaluate the effects of early time-restricted feeding on glycemia and inflammation independent of weight loss.

For their study, the researchers compared eTRF (80 percent of calories consumed before 1PM) to a usual feeding pattern (50 percent of calories consumed after 4PM) among ten participants with prediabetes and obesity.

The patients were randomized to eTRF or usual feeding patterns for the first seven days and were changed over to the alternative arm for the next 7 days. Food was provided to meet the patients’ caloric needs for weight maintenance to determine the weight-independent effects of this strategy. Patients wore continuous glucose (blood sugar) monitors throughout the study.

“We decreased the time these individuals were having high blood sugar levels with just one week of eTRF feeding,” said study senior author Jose O. Aleman, MD, PhD, assistant professor in the Department of Medicine, Division of Endocrinology, Diabetes, & Metabolism at NYU Grossman School of Medicine. “The findings show that eating a majority of one’s calories earlier in the day reduces the time that the blood sugar is elevated, thereby improving metabolic health.”  

Dr. Aleman and colleagues discovered the participants’ weights were stable throughout the study. Early time-restricted feeding led to a decreased mean amplitude of glycemic excursion and decreased time above range (blood glucose > 140mg/dL) compared to the usual eating pattern group. The time in range was similar between the eTRF and usual feeding pattern group.

“Based on this data, eTRF may be a helpful dietary strategy for diabetes prevention,” concluded Dr. Bruno. “Further studies are needed to understand the true overall benefit of these intervention strategies.”

Various medications can be prescribed to lower blood sugar levels in individuals at high risk for developing type 2 diabetes, but it’s often unclear which patients will benefit most from which drugs.

In a study published in Diabetologia, investigators at Massachusetts General Hospital (MGH), founding member of Mass General Brigham (MGB), identified genetic variants associated with response to two such drugs: metformin and glipizide. The findings may help personalize care to prevent and treat type 2 diabetes.

Current available treatments for type 2 diabetes do not consider an individual’s underlying genetics or disease pathophysiology, making it a burden to develop tailored interventions.

The team of investigators, co-led by Josephine Li, MD, endocrinologist in the Diabetes Unit at MGH and an Instructor in Medicine at Harvard Medical School, studied whether a genome-wide approach could unravel new pharmacogenetic associations and develop insight to understand the relevance of known genetic risk factors for type 2 diabetes.

In the Study to Understand the Genetics of the Acute Response to Metformin and Glipizide in Humans (SUGAR-MGH), researchers collected genetic data on 1,000 individuals at risk of developing type 2 diabetes who received a short course of metformin and glipizide. The team also documented patients’ blood sugar and insulin levels after receiving these drugs.

“We performed a genome-wide association study to comprehensively identify genetic variants associated with drug response. We also tested the influence of previously reported genetic variants for type 2 diabetes and glycemic traits on SUGAR-MGH outcomes,” says Dr. Li. “Our study was unique in that over a third of SUGAR-MGH participants were of non-European descent, in contrast to existing pharmacogenetic genome-wide association studies.”

Five genetic variants were significantly associated with acute response to metformin or glipizide. Three were more common in participants of African ancestry. One of these African ancestry–specific variants (called rs111770298) was confirmed in the Diabetes Prevention Program, where individuals with this variant experienced a weaker response to metformin treatment than participants without.

“Understanding the impact of ancestry-specific variants can help guide and tailor treatment selection for population subgroups in the future,” notes Li.

In a separate analysis, another variant (called rs703972), previously known to help protect against type 2 diabetes, was associated with higher levels of active glucagon-like peptide 1, a hormone that stimulates insulin secretion and reduces appetite.

“Next steps include functional experiments to confirm the implications of the novel genetic variants we’ve identified that are associated with the body’s response to these glucose-lowering therapies,” says Li.

“SUGAR-MGH is designed to allow investigators to use two commonly-used drugs with different mechanisms of action to probe the role of specific genes on glucose regulation,” says co–senior author Jose C. Florez, MD, PhD, chief of the Endocrine Division and the Diabetes Unit at MGH and a professor of Medicine at Harvard Medical School.