Scientists may have found a surprising new way to detect the early signs of obesity—by looking at the bacteria in our mouths.
A new study published in the journal Cell Reports has discovered that people with obesity have a different set of mouth microbes compared to people with a healthy weight. This discovery could lead to new tools to help prevent obesity before it starts.
Obesity is a serious health issue around the world. It’s defined as having a body mass index (BMI) of 30 or more. According to the World Health Organization, as of 2022, about 890 million people around the world are living with obesity, and more than 2.5 billion adults are overweight (with a BMI of 25 or more).
Being overweight or obese increases the risk of many health problems, including heart disease, diabetes, and certain types of cancer.
Many things can cause people to gain weight, including diet, lack of exercise, and genetics. Scientists also know that the bacteria in our digestive systems, known as the gut microbiome, can affect weight. But not much has been known about how the bacteria in our mouths might be linked to obesity.
To learn more, researchers at New York University Abu Dhabi studied the mouth bacteria of 628 adults living in the United Arab Emirates. Among them, 97 people had obesity and 95 people were at a healthy weight. The healthy-weight group was matched to the obesity group by age, lifestyle, and oral health habits to ensure the comparison was fair.
The researchers collected saliva samples and studied the microbial DNA. They found that people with obesity had more of a certain type of bacteria, such as *Streptococcus parasanguinis*, which is known to cause inflammation.
They also had more bacteria that produce a substance called lactate. High levels of lactate in the body are linked to poor metabolism and a higher risk of developing type 2 diabetes.
But the differences didn’t stop there. The researchers also found 94 differences in how the bacteria worked in people with obesity compared to those at a healthy weight. For example, in people with obesity, the bacteria were better at breaking down sugars and proteins in ways that may be harmful.
These processes led to higher levels of chemicals like uridine and uracil, which are known to increase hunger and food intake. The study also found that the bacteria in people with obesity were less able to make nutrients that help the body stay healthy.
Right now, scientists are not sure if these mouth bacteria changes are the cause of obesity or the result of it. But either way, spotting these changes early could be useful. The researchers believe that in the future, a simple mouthwash test could be used to detect these microbial warning signs before weight gain occurs.
If it turns out that the bacteria are part of the cause, new treatments could be developed to improve the balance of bacteria in the mouth, possibly preventing obesity altogether. This could be done through special mouthwashes, probiotics, or other ways to support a healthier oral ecosystem.
This new research opens a promising door for better understanding the links between oral health and weight. While more studies are needed, this work suggests that keeping an eye on our mouth bacteria could help us catch early signs of weight problems and create better ways to stop them from progressing.
If you care about weight loss, please read studies that hop extract could reduce belly fat in overweight people, and early time-restricted eating could help lose weight.
For more health information, please see recent studies that Mediterranean diet can reduce belly fat much better, and Keto diet could help control body weight and blood sugar in diabetes.
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