Inulins are a group of naturally occurring polysaccharides produced by many types of plants.
It is most often extracted from chicory.
The inulins belong to a class of dietary fibers known as fructans.
Inulin is used by some plants as a means of storing energy and is typically found in roots or rhizomes.
Most plants that synthesize and store inulin do not store other forms of carbohydrate such as starch.
It is approved inulin as a dietary fiber ingredient used to improve the nutritional value of manufactured food products.
Inulin is used to measure kidney function: used to determine glomerular filtration rate.
Inulin is a natural storage carbohydrate present in more than 36,000 species of plants, including agave, wheat, onion, bananas, garlic, asparagus, Jerusalem artichoke, and chicory.
For these plants, inulin is used as an energy reserve and for regulating cold resistance.
It is soluble in water, and osmotically active.
Certain plants can change the osmotic potential of their cells by changing the degree of polymerization of inulin molecules by hydrolysis.
By changing osmotic potential plants can withstand cold and drought during winter periods.
Inulin is a heterogeneous collection of fructose polymers, consisting of chain-terminating glucosyl moieties and a repetitive fructosyl moieties linked by β bonds.
Inulin is a type of dietary fiber that is found in certain foods such as chicory root, artichokes, and asparagus.
It is a prebiotic fiber, and not digested in the small intestine like other types of carbohydrates but rather passes through to the large intestine where it stimulates the growth of beneficial bacteria.
Some of the potential health benefits of inulin include:
Improved digestive health: promoting the growth of beneficial bacteria in the gut, thereby supporting digestive health.
It has been shown to improve bowel movements and alleviate constipation.
Lowers blood sugar: helps improve insulin sensitivity, thereby lowering blood sugar levels.
Improves bone health, increasing calcium absorption in the gut, which may help improve bone density and reduce the risk of osteoporosis.
Weight Loss: Inulin has a low calorie content and is able to promote feelings of fullness, so it may be helpful in reducing food intake and managing weight.
Lowers risk of Cardiovascular Disease: may help to lower triglyceride levels and reduce inflammation, both of which are risk factors for cardiovascular disease.
Inulin is generally safe for consumption.
Because of the β linkages, inulin is not digested by enzymes in the human alimentary system, contributing to its functional properties of reduced calorie value, dietary fiber, and prebiotic effects.
It is color and odorless, and has little impact on sensory characteristics of food products.
Oligofructose has 35% of the sweetness of sucrose, and its sweetening profile is similar to sugar.
Standard inulin is slightly sweet, while high-performance inulin is not.
Its solubility is higher than the classical fibers.
When mixed with liquid, inulin forms a gel and a white creamy structure, which is similar to fat.
Chicory root is the main source of extraction for commercial production of inulin.
The extraction process for inulin is similar to obtaining sugar from sugar beets.
Inulin is isolated, purified, and spray dried from chicory roots.
Inulin may also be synthesized from sucrose.
It is generally recognized as safe (GRAS) from the US Food and Drug Administration (FDA).
It is approved by the FDA as an ingredient to enhance the dietary fiber value of manufactured foods.
Its flavor ranges from bland to subtly sweet, at about 10% of the sweetness of sugar/sucrose.
It can be used to replace sugar, fat, and flour.
Inulin contains 25–35% of the food energy of carbohydrates (starch, sugar), and provides nutritional advantages by increasing calcium absorption and possibly magnesium absorption, while promoting the growth of intestinal bacteria.
Chicory inulin increases absorption of calcium in young women with lower calcium absorption and in young men.
It is a form of soluble fiber and is sometimes categorized as a prebiotic.
Inulin is also considered a FODMAP, a class of carbohydrates which are rapidly fermented in the colon producing gas.
Although FODMAPs can cause certain digestive discomfort in some people, they produce potentially favorable alterations in the intestinal flora that contribute to maintaining health of the colon.
Inulin has minimal increasing impact on blood sugar, and may potentially have use in managing blood sugar-related illnesses, such as metabolic syndrome.
Inulin helps measure kidney function by determining the glomerular filtration rate (GFR), which is the volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman’s capsule per unit time.
While inulin is the gold standard for measuring the GFR, it is rarely used: requires intravenous (IV) access for the infusion of inulin as well as up to twelve blood samples taken from the patient over the course of four hours.
Dietary supplementation with inulin-type fructans reduced blood levels of low-density cholesterol, a biomarker of cardiovascular disease.
The side effects of inulin dietary fiber diet, which may occur, usually in sensitive persons, are:
Intestinal discomfort, including flatulence, bloating, stomach noises, belching, and cramping
Inflammation – inulin can cause an allergy-related type of inflammation in the gut and lungs.
Inulins are polymers composed mainly of fructose units (fructans), and typically have a terminal glucose.
Inulin is uniquely treated by nephrons in that it is completely filtered at the glomerulus but neither secreted nor reabsorbed by the tubules, allowing the clearance of inulin to be used clinically as a highly accurate measure of glomerular filtration rate (GFR) — the rate of plasma from the afferent arteriole that is filtered into Bowman’s capsule measured in ml/min.
Inulin is indigestible by the human enzymes ptyalin and amylase, which are adapted to digest starch.
It passes through much of the digestive system intact.
Only in the colon do bacteria metabolise inulin, with the release of significant quantities of carbon dioxide, hydrogen, and/or methane.
Inulin-containing foods can be rather gassy, in particular for those unaccustomed to inulin, and these foods should be consumed in moderation at first.
Inulin is a soluble fiber, one of three types of dietary fiber including soluble, insoluble, and resistant starch.
Some soluble fibers may help lower blood cholesterol and glucose levels.
Normal digestion does not break inulin down into monosaccharides, it does not elevate blood sugar levels and may, therefore, be helpful in the management of diabetes.
Inulin also stimulates the growth of bacteria in the gut.
It passes through the stomach and duodenum undigested and is highly available to the gut bacterial flora, similar to resistant starches and other fermentable carbohydrates.
Some traditional diets contain over 20 g per day of inulin or fructo-oligosaccharides.
Foods naturally high in inulin or fructo-oligosaccharides, such as chicory, garlic, and leek.
Clinical trials have found it causes gastrointestinal adverse effects such as bloating and flatulence, does not affect triglyceride levels or development of fatty liver, may help prevent traveler’s diarrhea, and may help increase calcium absorption in adolescents.
Plants that contain high concentrations of inulin include:
Banana and plantain