We are big proponents of bitters for digestive health. Bitter fruits and vegetables are an important source of vitamins, trace minerals, fiber, and antioxidants. But there are more reasons to include bitter plants in your diet than just nutrition.
Researchers studying the bitter substances found in plants are building a strong case for why you should take bitters for digestive health – as well as for their many other potential health benefits.
In this post we will look at how some of this research supports the traditional uses of bitters for digestive health with our list of 6 Reasons To Try Bitters for Digestion.
We will also leave you with some thoughts on some of the emerging research on how bitters for digestion might offer health benefits in many other ways – some which may surprise you.
For more about the benefits of bitter foods, see our posts on Bitter Healing Plants, What Foods are Bitter, the Beauty of Bitter Flavors, and our list of 17 Bitter Foods and 24 Bitter Spices for the kitchen.
To learn how to take bitters for digestion, see our post on Digestive Bitters.
Let’s start by looking into how and why our bodies respond to bitter flavors.
Why We Taste Bitter Flavors
The key to understanding the potential for digestive health and bitters begins with the question of why we can detect bitter flavors in the first place. As it turns out, our ability to taste bitterness is only the beginning.
The consensus among researchers is that our ability to taste bitter flavors adapted as a defense mechanism against toxic substances.
In nature, bitter and sour flavors are often associated with harmful plants. But many healthy plants we consume contain a variety of flavor profiles, bitterness included. So the defensive notion of bitter receptors is only part of the story.
You may remember those tongue diagrams from school. But when it comes to bitter flavors, the notion that specific areas of the tongue correspond with specific flavors is out-dated.
We now know that our ability to sense taste is much more complex. In fact, the more our ability to sense different flavors is studied, the more complex the question of “why do we taste bitter flavors?” becomes.
Researchers have discovered that bitter taste receptors are located throughout our digestive tract. Further, those receptors are involved in many functions other than just detecting potentially toxic substances.
Research into bitter flavors and how these receptors react to bitterness is rapidly expanding our knowledge of how bitter plants affect digestion. In fact, bitters for digestion seems to be just the beginning of a long list of ways that bitter substances and our bodies interact.
Even though there is much more to be discovered, the research to-date clearly indicates that our natural response to bitter substances impacts a lot more than just our digestive health.
We will get into more detail about those discoveries in our list of 6 Reasons Why You Should Use Bitters. First let’s take a closer look at how bitters for digestion works.
Bitter Taste Receptors
The importance of bitter flavors is reflected in the extensive and intricate nature of how our bodies detect bitter substances. The bitter taste we experience is just the beginning. Our bodies react to bitter flavors through taste, but also through numerous other means by way of bitter-specific receptors.
Research by Wolfgang Meyrhoff at the German Institute of Human Nutrition has made significant headway into our understanding of the function of our bitter taste receptors. His work has revealed that these unique taste receptors, called TAS2R or T2R’s, are able to sense over 100 different bitter taste profiles.
These T2R bitter receptors mediate several activities across the neural, vascular, and endocrine (hormone) systems. This means those bitter chemicals that we ingest – be it from plants we eat or toxic substances, trigger responses throughout our nervous system and circulatory system. The unique nature of these receptors also means bitter substances can influence how and when some hormones are released.
How Bitter Receptors Work
The bitter receptors act as chemical detectors that can detect harmful substances and initiate localized responses. But they can also trigger immune responses and the release of hormones that control appetite regulation and insulin sensitivity(1).
So returning to the question of why we taste bitter flavors: the bitter taste receptors in our digestive tract are able to detect both harmful chemicals and healthy chemicals and then react accordingly(2).
In fact, bitter receptors have a unique structure to accommodate this good/bad bitter sorting ability. The receptors have two “sides.” One side is attuned to detect a broad range of bitter molecules, while the other side is more finely tuned for specific toxic substances.(3)
The toxic screening capability is also likely why T2Rs are found in our airways. Bitter receptors can detect changes caused by invasive microbes that mimic bitterness and then signal a localized immune response to combat those dangerous microbes(4).
Bitter Receptors in Digestion
Bitter receptors are not just in our digestive tract and airways; they are located throughout our bodies, including our skin.
The extensive presence of bitter receptors suggests our relationship with bitter substances is far reaching. Those bitter receptors on your tongue may be the first – and most notable, way you experience bitter chemicals, but they are only a small fraction of those found throughout your digestive tract and elsewhere.
One of the most notable aspects of the bitter-specific T2R receptors found in your digestive tract is that they are found on enteroendocrine cells.
Enteroendocrine cells are located in the mucosal membrane of the digestive tract. These are specialized cells that can detect bitterness but can also control the release of gastrointestinal hormones that control our hunger and fullness signaling, as well as the metabolism of fat and carbohydrates (5)(6).
So there is a relationship between the detection of bitterness in the gut and the release of hormones that control things like appetite, digestive juices, satiety, and other metabolic functions.
Bitter Hearts & Minds
If enteroendrocrine receptors aren’t impressive enough, bitter receptors are also found on the heart, arteries in the brain, and in smooth muscle tissues. Smooth muscles control the involuntary muscle movements responsible for internal functions like digestion, respiration, and circulation.
Researchers believe that the receptors on the heart, vascular system, and smooth muscles are why bitter chemicals seem to influence the regulation of blood flow(7).
When bitter substances stimulate receptors in these areas, the smooth muscles tend to relax. This may be why many bitter herbs tend to have anti-spasmodic properties. It is also part of why bitters for digestion can help ease stomach cramping and bloating by stimulating the digestive muscles to relax.
These smooth muscle reactions in response to bitters also help increase blood flow to the digestive tract. In fact, the increased blood flow response can happen in as little as five minutes after ingesting bitter foods(8). This effect is particularly noted in the research with the herbs gentian and wormwood but also may help explain why bitter medicinal herbs like vervain have notable anti-spasmodic properties as well.
Unlike most stimulus and receptor pairs in the human body, T2R expression increases the more that the stimulus (bitterness) is presented. So the more we taste bitter, the more we experience its effects(9). This same research team also identified how the taste receptors on the tongue signal to the brain to produce increased oral and gastric secretions, including bile and digestive enzymes(10).
We can see that the relationship between digestive health and bitters is indeed intricate and unique. But what does all this mean? Well, it means that you should consider reuniting yourself with bitter substances in your diet or even adding a digestive bitters supplement to your daily regimen. Here are six reasons why.
6 Reasons You Should Use Bitters for Digestive Health
Bitter foods and bitter herbs have a long and well-documented history as a digestive aid. The use of bitters for their digestive benefits is consistent across many different cultures and medicinal systems. Based on our review of research on bitters and digestion, as well as the traditional uses recommended in Traditional German Medicine here are our 6 Reasons to explore digestive health and bitters.
1. Bitters improve nutrient absorption
We know from the research above that when our bitter taste receptors detect bitterness, they signal the brain to increase gastric secretion and decrease gastric motility during digestion.
The research above also indicates that bitter flavors can increase blood circulation to your digestive tract in as little as five minutes after you ingest bitter foods. So you can still get the benefits of bitters whether you take them before, during, or after your meals.
Increased gastric secretions of digestive enzymes and bile coupled with slower motility means improved breakdown of nutrients and slower delivery of nutrients (including sugar) to the bloodstream.
This is also significant as it relates to blood sugar levels. Proper blood sugar is not only critical in maintaining good health, but reducing blood sugar volatility helps maintain proper appetite control and prevents more serious conditions like insulin sensitivity and diabetes.
2. Bitters reduce after-meal glycemia
Research shows that bitter substances can slow down the digestive movement of carbohydrates into the small intestine, which can help reduce after meal blood sugar spikes, or glycemia.
When food enters your digestive tract it is broken down into macronutrients (fat, carbohydrates, and proteins) by gastric juices and digestive enzymes.
The carbohydrates (sugar) that are derived from your food enter your blood stream in your small intestine. Slowing down this progression seems to also spread out the duration of sugar entering the blood stream.
One of the problems of a high-sugar diet is the resulting “spike” in post-meal blood sugar. Diabetics and pre-diabetic people with insulin sensitivity are particularly prone to these spikes. Over time, repeated blood sugar spikes are associated with developing metabolic syndrome and diabetes.
3. Bitters help you feel full sooner (and for longer)
The same reduction in gastric motility that helps with nutrient absorption and in the reduction of blood sugar volatility also helps you feel full – and for longer after meals.
The feeling of fullness, or satiety, is an important part of appetite control that helps regulate caloric intake. The earlier into a meal you feel fullness, the less you will eat. So, bitterness helps with appetite control in addition to digestion.
4. Bitters reduce gas, bloating, acid reflux, and digestive discomfort
The combination of digestive health and bitters makes sense to help prevent gas, bloating, and other discomfort like cramping is one of the oldest and most reliable indications. Research seems to back this up. When the bitter receptors on our tongues detect bitterness, they immediately signal the brain to release oral and gastric secretions.
The increased secretions help break down food more efficiently. This, coupled with the increased blood flow and slower gastric movement, seem to significantly reduce indigestion, gas, and acid reflux.
5. Bitters for appetite control & weight loss
Much like how bitterness can slow gastric motility to help promote appetite control and a feeling of satiety, bitter flavors can also activate the enteroendocrine cells in our digestive tract.
When these cells detect bitterness, they release peptide YY (PYY) and glucagon-like-protein 1 (GLP-1), which are the hormone-like substances that make us feel full.(11)
This is fascinating not just because it can shut down hunger and make us feel full, but also because the unique nature of the receptor cells means that the reaction does not have to operate through the central nervous system. This means that bitters may act directly as localized hormone triggers to control appetite and other metabolic functions in digestion.
These hormonal triggers in the GI can reduce appetite and increase satiety, which leads to a reduced caloric intake and thus potential weight loss.
6. Bitters help promote a healthy gut biome
The beneficial bacteria found in our digestive tract is responsible for a number of essential functions that affects nutrient absorption, immune system health, mood, sleep, and more. Maintaining a healthy gut is foundational to overall health and wellness.
Research indicates that certain herbal bitters, loosely known as “nutritive bitters”, contain meaningful amounts of prebiotic starches that promote the growth of beneficial bacteria and can have beneficial effects on regulatory bowel function.(12) Examples of nutritive bitters include dandelion, chicory, angelica, and burdock.
Over time, these improvements can lead to lower blood glucose, lower blood lipid levels, and better satiety. Another small study showed that these nutritive bitters combined with calcium significantly reduced body mass, relative to a placebo, over the course of a year.(13)
Some researchers speculate that the increase in beneficial bacteria may also improve the gut hormone signaling associated with proper appetite regulation.
Additional Thoughts on the Benefits of Medicinal Bitters
The interrelated actions of bitter substances on our bitter receptors play a role in many important functions. So it’s not just bitters for digestion, but also bitters for better health.
The widespread effects of digestive health and bitters we’ve covered above are just one small part of the growing body of research on the health benefits of bitters. There is great potential for bitters as a means to prevent and treat a wide variety of ailments, or just to maintain our overall health and wellness.
Here are some emerging areas of research that may lead to some amazing benefits of bitters.
Anti-inflammatory- Bitters used to treat asthma
A team led by Ronghua ZhuGe of the University of Massachusetts Medical School has uncovered how bitter compounds might be used to open up the airways in asthmatics.
Currently, the main treatment of asthma is with bronchodilators. But these drugs can have many side effects. Further research of these natural bitter compounds may present opportunities as a treatment for asthma and other airway diseases.
The research team found that by using bitter compounds they could open up the airways in mice. The study also used a new method of screening bitter compounds to determine which ones are potentially effective bronchodilators.
Researchers believe that the bitter substances trigger the bitter receptors (TAS2Rs) located in the smooth muscle cells in the airways, causing the muscles to relax and the airway to open. But how this action actually happens is under dispute, so much more research is required.(14)
Bitters for immune system health
One of the activities of the T2Rs found in our respiratory system is to monitor the surrounding tissues for bacteria and then stimulate an immune response if pathogens begin to grow. When bacteria congregate, they begin to “communicate” by releasing chemicals. These chemicals are called homoserine lactones.
Homoserine lactones are chemically similar to bitter compounds found in plants. These lactones trigger T2R activation, which then causes the epithelial cells to release antibacterial compounds to rid the surrounding area of the bacteria.(15)
Bitters to combat sugar-fed “Bad” bacteria
When we stop eating bitters, we tend to compensate with more sweet. This seems to be the story of our Western diet, which has all but abandoned bitters in favor of sweet. Bitters help balance our cravings, particularly for sugar.
In addition, sugar and bitterness seem to be at odds when it comes to our immune response. Sweetness tends to suppress the immune response. And we already know that bacteria love sugar.
As invasive bacteria consume sugar, they increase their production of those lactones molecules. The bitter receptors respond to the presence of these bitter chemicals and signal the immune responses in surrounding cells.(16)
Some researchers are exploring whether or not introducing bitter substances can have a similar effect, thus helping to combat the spread of bad bacteria. This effect would be particularly important in the digestive tract, a significant part of your overall immune system.
Obesity, Diabetes, & Weight Loss- Our taste for bitterness related to obesity
Yes. But there are a lot of variables to consider. In any case, it seems that our ability to taste and respond to bitterness doesn’t just vary by individual naturally, but it is also a function of how much bitter stimulus we receive.
In the absence of bitterness (as in the modern American diet) the activity of our bitter receptors appears to decrease beyond what some researchers consider to be “normal”. In his book “The Male Herbal”, James Green coined this below-normal level of bitterness detection as “bitter deficiency syndrome”.
Researchers found that women and children who perceive a higher level of bitterness have much lower levels of obesity. Luckily, applying regular bitter stimuli can restore a normal level of bitterness detection.(17)(18)
Further, people with a high sensitivity for bitterness have improved blood glucose control.(19)
Natural bitters help regulate appetite
The regulation of appetite involves a lot of different mechanisms. But research does indicate that bitter flavors activate receptors cells in several different locations within the digestive system that have an impact on hunger, satiety, how carbohydrates and fats are metabolized or stored, as well as a number of responses relating to blood sugar and insulin.
Research continues to explore how these multiple avenues of bitter receptor responses control appetite, improve digestive efficiency, and support healthy metabolism of carbohydrates and sugars resulting in reduced levels of obesity and metabolic syndrome.
Metabolic syndrome is the cluster of conditions relating to high blood sugar, blood pressure, and body fat that is associated with high risk of heart disease, stroke, and diabetes.(20)
Bitters to prevent (or treat) insulin resistance and diabetes
As the research above indicates, bitters are closely involved in the metabolism of carbohydrates and the corresponding insulin response through both mechanical and hormonal mechanisms.
The receptor cells in the tongue also communicate with the brain. So researchers are investigating how bitters might be used therapeutically to correct episodes of hypoglycemia (elevated blood sugar) in non-insulin dependent patients.
They are looking into the bitter receptor and brain connection in order to trick the brain into thinking that food is being consumed. Researchers hypothesize that bitters can signal a satiety response in the brain by merely tasting bitterness. This would bypass the need to consume any food.
In this case, bitters would be highly effective at curbing the sugar cravings that commonly accompany hypoglycemic episodes.(21)
- Sternini, Catia, Laura Anselmi, and Enrique Rozengurt. “Enteroendocrine cells: a site of ‘taste’in gastrointestinal chemosensing.” Current opinion in endocrinology, diabetes, and obesity 15.1 (2008): 73.
- Jeon, Tae-Il, Young-Kyo Seo, and Timothy F. Osborne. “Gut bitter taste receptor signaling induces ABCB1 through a mechanism involving CCK.” Biochemical Journal 438.1 (2011): 33-37
- Thomas, Anu, et al. “The Bitter Taste Receptor TAS2R16 Achieves High Specificity and Accommodates Diverse Glycoside Ligands by using a Two-faced Binding Pocket.” Scientific Reports7.1 (2017): 7753.
- Workman, Alan D., et al. “The role of bitter and sweet taste receptors in upper airway immunity.” Current allergy and asthma reports 15.12 (2015): 72.
- Posovsky C., Wabitsch M, “Regulation of Appetite, Satiation, and Body Weight by Enteroendocrine Cells” Part 1: Characteristics of Enteroendocrine Cells and Their Capability of Weight Regulation. Horm Res Paediatr 2015; 83:1-10.
- Palatini, Kimberly, et. Al. “Diverse Classes of Bitter Phytochemicals Modulate Carbohydrate Metabolism and Immune Response Through Gastrointestinal Bitter Taste Receptors.” The FASEB Journal 19.1 Supplement 2015:405-5
- Chen, Jing-Guo, et al. “The expression of bitter taste receptors in mesenteric, cerebral and omental arteries.” Life sciences 170 (2017): 16-24.
- McMullen, Michael K., Julie M. Whitehouse, and Anthony Towell. “Bitters: time for a new paradigm.” Evidence-Based Complementary and Alternative Medicine 2015 (2015).
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- Meyerhoff, W. “Human Bitter Taste Perception” Chemical Senses, 2005.
- Janssen, S. et. Al. “Bitter Taste Receptors and alpha-Gustducin Regulate the Secretion of Ghrelin with Functional Effects on Food Intake and Gastric Emptying.” 2011. Proc. National Academy of Science USA 108, 2094-2099.
- Nishimura, Mie, et. Al. “Effects of the Extract from Roasted Chicory (Cichorium intybus L.) Root Containing Inulin-type Fructans on Blood Glucose, Lipid Metabolism, and Fecal Properties.” Journal of Traditional and Complementary Medicine. 2015
- Abrams, Steven A., et. Al. “Effect of Prebiotic Supplementation and Calcium Intake on Body Mass Index.” The Journal of Pediatrics 2007 151.3:293-298.
- Zhang C-H, Lifshitz LM, Uy KF, Ikebe M, Fogarty KE, et al. (2013) “The Cellular and Molecular Basis of Bitter Tastant-Induced Bronchodilation.” PLOS Biology. 10.1371
- Carey, Ryan M., et al. “Taste receptors: regulators of sinonasal innate immunity.” Laryngoscope Investigative Otolaryngology 1.4 (2016): 88-95.
- Verbeurgt, Christophe, et al. “The human bitter taste receptor T2R38 is broadly tuned for bacterial compounds.” PloS one 12.9 (2017): e0181302.
- Feene E., O’Brien S., Scannnell, A., Markey A., Gibney ER. 2011 “Genetic Variation in Taste Perception: does it have a role in healthy eating?” Proceedings of the Nutritional Society. 70(1):135-43.
- Negri, Rossella, et. Al. “Taste Perception and Food Choices.” 2012 Journal of Pediatric Gastroenterology and Nutrition 54.5:624-629.
- Dotson, Cedrick D., et. Al. “Bitter Taste Receptors Influence Glucose Homeostasis.” 2008 PLOS one 3.12
- Calvo, Sara Santa-Cruz and Josephine M. Egan. “The Endocrinology of Taste Receptors.” Nature Review Endocrinology 2015 11.4:213-227.
- Dotson CD, Vigues S., Steinle NI, Munger SD. “T1R and T2R receptors: the modulation of incretin hormones and potential targets for the treatment of type 2 diabetes mellitus.” Current Opinion Investigating Drugs 2010; 11:447-454.