Gut Bacteria May Impact Body Weight, Fat and Good Cholesterol Levels

11 Sep 2015 --- Link discovered between bacteria in the gut and body weight, triglycerides and “good” cholesterol (HDL) levels. Researchers from the University Medical Center Groningen in the Netherlands have identified 34 specific digestive tract microorganism species that influence weight and lipid metabolism, according to new research in Circulation Research, an American Heart Association journal.

Using state-of-the-art deep sequencing technology, researchers studied the association between gut microbes and blood lipid levels in 893 people in the Netherlands. They identified: 34 different types of bacteria contributed to differences in body fat (BMI) and blood lipids such as triglycerides and the good cholesterol known as high-density lipoprotein or HDL. Most were new associations. Surprisingly, gut bacteria had little relationship with bad cholesterol (low-density lipoproteins or LDL ) or total cholesterol levels.

It is already known that microbes and humans have a symbiotic relationship. The human body contains trillions of microorganisms, 10 times the number of human cells. These microbes help us to digest food and train our immune systems. The bacterial community in the human gut has been referred to as an extra organ because of its important role in an individuals’ health, researchers said.

“Our study provides new evidence that microbes in the gut are strongly linked to the blood level of HDL (good cholesterol) and triglycerides and may be added as a new risk factor for abnormal blood lipids, in addition to age, gender, BMI and genetics,” said Jingyuan Fu, Ph.D., study lead author and associate professor of genetics at the university. He goes on to say, “In total, we identified 34 bacterial species associated with BMI, triglycerides and HDL and several previously described bacterial associations which were associated with low BMI. We confirmed that these BMI-associated bacteria also associated with lower levels of triglycerides and higher levels of HDL., indicating the role of these bacteria in human metabolism.”
“As less than 30 percent of bacteria in the human gut have been cultured, we know very little about who they are and what they do. With state-of-art deep sequencing technology, we are now able to identify them,” Fu said.

While additional studies are needed in a larger and diverse population to test their hypotheses, researchers believe these findings may someday open the door to new therapies to alter the gut bacteria types that contribute to body weight, fat and cholesterol levels to help aid in the prevention of heart disease. Jing says, “From gut to heart: gut bacteria is another risk factor for heart diseases. Unlike other risk factors like age, gender, genetic risk, gut bacteria is changeable by intervention. However, at current stage, this field is still in its infancy. It will be essential to identify the causal axis of microbiome-lipids-CVD and to gain more insight into the gut bacteria functions. Moreover, dietary factors are an important player in shaping the gut microbiome and the risk for heart disease. We need to include dietary factors into this picture.”