Metabolic health can be defined by several clinical markers, including blood pressure, blood sugar, and blood lipid levels. Metabolic syndrome refers to a cluster of biological risk factors that can lead to chronic conditions like diabetes, heart disease and other health problems . It is estimated that more than 3 in 10 adults in the United States suffer from metabolic syndrome . Good metabolic health can help lower your risk of developing such disorders.
Other than lifestyle changes such as engaging in regular exercises, improving sleep and managing stress, dietary changes also help support our metabolic health and processes. Apart from reducing the consumption of sugar and fats, increasing the intake of prebiotics (whether via food or supplements) should also be considered. Read on to understand more about prebiotics and how they help improve and support our metabolic health.
As defined by the International Scientific Association for Probiotics and Prebiotics (ISAPP), a prebiotic is defined as a substrate that is selectively utilized by host microorganisms conferring a health benefit .
Our gut consists of trillions of microorganisms including bacteria, viruses, fungi and protozoa species. This composition of microorganisms is termed the gut microbiotaand is unique to everyone. It varies due to several factors such as environmental, lifestyle, dietary habits, and consumption of medications such as antibiotics . An optimum gut microbiota consists of a healthy balance of both good and bad gut bacteria species.
Prebiotics feed and enable the proliferation of good gut bacteria, which in turn crowd out the bad ones. This healthy balance of gut microbiota and optimum gut health leads to improved overall well-being, including benefits to our metabolic health.
One aspect of metabolic health is blood cholesterol level. Studies have shown that a healthy balance of gut microbiota may lower blood cholesterol levels through several mechanisms. One mechanism is the metabolizing of cholesterol into coprostanol, which reduces cholesterol absorption [5,6].
Good gut bacteria feed on prebiotics in a process called fermentation, which produces short-chain fatty acids (SCFAs). SCFAs like butyrate and propionate may also have cholesterol-lowering effects by controlling and inhibiting liver cholesterol synthesis .
Prebiotics may also have a direct effect on lowering cholesterol levels. Prebiotics, many of which are dietary fibers, move to the colon largely unchanged and undigested. This helps to increase the viscosity of the digestive tract, leading to decreased absorption of cholesterol and blood cholesterol levels .
Blood sugar is another aspect of metabolic health. Apart from cholesterol levels, the metabolites of the fermentation process also influence sugar metabolism and homeostasis. SCFAs such as butyrate act as signaling molecules and activate receptors involved in secreting chemicals called glucagon-like peptide 1 (GLP-1). GLP-1 is crucial in blood glucose metabolism by increasing insulin release .
SCFAs also directly impact sugar metabolism, by improving glucose metabolism in the liver and increasing sugar uptake by the body cells .
For prebiotics which are dietary fibers, they also support healthy blood pressure. The use of fibers to reduce blood pressure has been studied and published in various clinical trials. A meta-analysis has shown that fiber supplementation at 11.5g per day was able to decrease blood pressure . The Dietary Approaches to Stop Hypertension (commonly known as the DASH diet) also recommends a high-fiber intake as one of the many recommendations to reduce blood pressure.
The gut microbiota and SCFAs produced from the fermentation of prebiotics can also affect blood pressure. SCFAs activate receptors that play a part in blood pressure regulation. Unhealthy gut microbiota also leads to chronic low-grade inflammation which can be a cause of high blood pressure as well .
Metabolic health disorders are on the rise across the world. Besides lifestyle modifications such as regular physical activity, managing stress and having adequate sleep, dietary modifications also help. Prebiotics enhance the gut microbiota and optimize gut health, which in turn support metabolic health such as blood pressure, sugar and cholesterol levels as shown in various studies.