March 17, 2023 — Having a higher level of caffeine in the blood may reduce body fat and the risk of type 2 diabetes, according to a new study Posted in BMJ Medicine.
Although more research is needed, the findings open up possibilities for the role calorie-free caffeinated beverages might play in reducing the risk of obesity, diabetes and other conditions.
“Caffeine has been implicated in metabolism and is commonly consumed in beverages. It is therefore important to better understand what causal effect this might have on metabolism,” said study lead author Dipender Gill, PhD, professor of epidemiology at Imperial College London.
“However, we would like to emphasize that individuals should not change their dietary or lifestyle preferences based solely on the results of our study,” he said. “Further validation in the form of clinical trials is warranted first. Additionally, too much caffeine can also have harmful effects, so a balance is needed.
Previous studies have shown that drinking 3 to 5 cups of coffee per day is associated with a lower risk of type 2 diabetes and heart disease and that drinking 100 milligrams of caffeine per day can increase energy expenditure by about 100 calories per day. An average cup of coffee contains about 70 to 150 milligrams of caffeine.
However, most published research has focused on observational studies, which do not prove cause and effect. Many other factors could be involved, including other ingredients in caffeinated foods and drinks, according to lead author Susanna C. Larsson, PhD, of the Karolinska Institute in Stockholm, Sweden, and her colleagues. colleagues.
Katarina Kos, MD, PhD, senior lecturer in diabetes and obesity at the University of Exeter, UK, agrees. She said this genetic study “shows links and potential health benefits for people with certain genes attributed to a [caffeine] …metabolism as an inherited trait and potentially better metabolism.”
“It does not study or recommend drinking more coffee, which was not the purpose of this research,” she added. told the UK Science Media Center. Kos was not involved in this study.
In the new analysis, the researchers looked at data from 10,000 people of mostly European ancestry who took part in six long-term studies.
They looked at two specific genetic mutations that have been linked to a slower rate of caffeine metabolism. In general, people with these two common genetic variants will have higher blood caffeine levels after consuming coffee or other caffeinated beverages than those with faster caffeine metabolism.
They then looked at how caffeine levels tracked body fat, the risk of type 2 diabetes, and the risk of major heart diseases such as coronary heart disease, stroke, heart failure, and irregular heartbeat.
Both genetic variants resulted in “genetically predicted higher plasma caffeine concentrations across the lifespan,” the researchers note, “and were associated with lower body mass index and fat mass, as well as lower lower risk of type 2 diabetes”.
There were no strong associations in this study with a lower risk of developing any of the major heart diseases.
They found that weight loss contributed about 43% of caffeine’s effect on type 2 diabetes risk.
“The finding that higher levels of caffeine in plasma can reduce body weight and risk of type 2 diabetes appears to be consistent with what is known about its effects on metabolism,” Gill said. “We are now exploring the broader effects of caffeine on health outcomes and the potential mechanisms that might be behind this.”
The researchers noted several limitations, including that they only studied two genetic variants and that the study participants had mostly European ancestry. They also stressed caution before drawing strong conclusions or changing behavior.
Kos agrees. “When considering coffee consumption and caffeinated energy drinks, one should be aware of the potential negative offset by excess calories in the form of sugar and fat in many of these drinks,” he said. she noted.
“Even for the option of increasing the use of calorie-free caffeine drinks, a benefit has yet to be proven,” Kos said.