The Importance Of Fiber For Our Health

Fiber is an essential part of a healthy diet that provides numerous benefits, not just for the health of our gut. There are many studies showing that a high-fiber diet can reduce the risks of many health problems, including cardiovascular disease, type 2 diabetes, and certain cancers. But what exactly is fiber and what makes it so good for our health?


For a long time fibers were considered boring, or completely forgotten. Many people associate fiber with a powder that you should drink if you have problems with your bowel movements. The standard Western diet is almost completely low in fiber and most diets focus heavily on avoiding carbohydrates, supplementing with protein or fat. From a nutritional perspective, a fiber is a complex carbohydrate and is mostly found in vegetables, fruits, whole grains and legumes.


There are two types of fiber – soluble and insoluble – and both play an important role in health. Insoluble fiber does not dissolve in water and adds bulk to the stool, while soluble fiber absorbs water and forms a jelly-like substance in the digestive system.


You've probably heard that there are a huge number (39 trillion!) of microorganisms, most of them bacteria, that live in our gut and each have their own purpose. They are called the gut macrobiome and play an important role not only in metabolism, but also in immunity, hormonal balance, cognition and gene expression. Everything we consume will be processed by these microbes, but not every microbe eats the same food. To keep the macrobiome diverse and balanced, we need to consume a variety of plant foods.


Plants have a monopoly on fiber and our microbes love fiber. By removing a lot of plants from our diet (carbohydrate fear, lectin fear, Keto hype etc.) we are “starving” our gut microbiome. The population of the microbes becomes sparse and not varied enough and they live in dysbiosis. This codependency between healthy microbiomes and variety in plants we consume was discovered by Dr. Rob Knight in the largest and most diverse study of microbes and microbiomes – the American Gut Health Project he initiated in 2012 and continues to this day continues.


The microbes in our gut are also called probiotics and together with prebiotics (fiber) they create compounds called postbiotics. Postbiotics include nutrients such as vitamins B and K, amino acids, substances called antimicrobial peptides that help slow the growth of harmful bacteria, and substances that short chain fatty acids (SCFA) and which help healthy bacteria flourish.


There are three main types of SCFA and each type of fiber we consume produces a different mix of these SCFA after being digested by good bacteria. SCFA have anti-inflammatory, antitumorigenic and antimicrobial effects. They alter intestinal integrity and maintain a functional immune system.


SCFA play an important role in the fine-tuning of the brain-gut axis, a feedback system vital not only for the proper maintenance of gastrointestinal and metabolic functions, but also for the regulation of food intake and energy expenditure. SCFA can also affect brain function and behavior. For example, studies in patients with Parkinson's disease showed they had reduced levels of SCFA in their stools compared to healthy controls, and patients with bipolar disorder showed lower levels of one type of SCFA-producing bacteria.


To reap the benefits of SCFA, we need prebiotic fibers that feed healthy gut microbes to create healthy postbiotics. Most soluble fiber is prebiotic and most insoluble fiber is not. In nature, there are countless types of soluble fiber and each plant provides a unique blend of fiber which then in turn requires a uniquely diverse blend of microbes to process it. So the more plant and fiber diversity, the more diverse the microbiome ecosystem in our gut and the more SCFA are produced for our optimal health.






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Monika DeBoer


I offer holistic energetic therapy and nutritional coaching that appeals to you as a unique and whole person. I am also a teacher of Energetic Massage at Healing Space Institute in Bussum, the Netherlands. My mission is to help people live in a state of optimal health and wellness and reconnect them with their body's innate wisdom and healing power.


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