The Metabolites We Test

Using just a pinprick of blood, Ixcela measures gut-specific metabolites to provide a personalized wellness plan that helps you feel and look great. Below is a list of metabolites we test. These metabolites are either produced by, or used by your gut microbiome. Since reporting indivdual values is not that helpful for most people, Ixcela results show how these metabolite levels impact five areas of health: Gastrointestinal Fitness, Immuno Fitness, Cognitive Acuity, Emotional Balance, and Energetic Efficiency.


Ixcela Tests Key Metabolites in Your Gut

Metabolite Name

Indole-3-Propionic Acid

Indole-3-Propionic Acid

Indole-3-Propionic Acid

Indole-3-Propionic Acid

Indole-3-Propionic Acid

Indole-3-Lactic Acid

Indole-3-Lactic Acid

Indole-3-Lactic Acid

Indole-3-Lactic Acid

Indole-3-Lactic Acid

Indole-3-Acetic Acid

Indole-3-Acetic Acid

Indole-3-Acetic Acid

Indole-3-Acetic Acid

Indole-3-Acetic Acid

Tryptophan

Tryptophan

Tryptophan

Tryptophan

Tryptophan

Serotonin

Serotonin

Serotonin

Serotonin

Serotonin

Kynurenine

Kynurenine

Kynurenine

Kynurenine

Kynurenine

Total Indoxyl Sulfate

Total Indoxyl Sulfate

Total Indoxyl Sulfate

Total Indoxyl Sulfate

Total Indoxyl Sulfate

Tyrosine

Tyrosine

Tyrosine

Tyrosine

Tyrosine

Xanthine

Xanthine

Xanthine

Xanthine

Xanthine

3-Methylxanthine

3-Methylxanthine

3-Methylxanthine

3-Methylxanthine

3-Methylxanthine

Uric Acid

Uric Acid

Uric Acid

Uric Acid

Uric Acid

Our test is backed by scientific studies. Learn more about the metabolites we test as well as relevant references.

Learn More About Each Metabolite

Indole-3-Propionic Acid (IPA)

Indole-3-Propionic Acid (IPA)

  • Indole-3-propionic acid (IPA), a strong neuroprotective antioxidant, is a key indicator of a healthy gut microbiome.[1,2]
  • IPA plays a crucial role in regulating intestinal permeability.[3] Healthy intestines allow nutrients to pass into the bloodstream, but prevent potentially harmful substances from migrating to areas of the body where they could cause inflammation and gastrointestinal (GI) distress.
  • Low levels of IPA may indicate a weak population of the bacterial colony Clostridium sporogenes, a beneficial bacterial strain in the gut.[3]
Indole-3-Lactic Acid (ILA)

Indole-3-Lactic Acid (ILA)

  • Indole-3-lactic acid (ILA) is found in fermented foods and produced by some gut bacteria from the amino acid tryptophan.
  • Proper levels of ILA are important for the production of other essential metabolites, like indole-3-propionic acid (IPA).[6]
  • Low or high levels of ILA may indicate gut bacteria dysbiosis (bacterial imbalance), which can lead to a variety of adverse symptoms, including gastrointestinal (GI) distress, inflammation, poor immune system, sleep disturbances, skin inflammation, and negative health outcomes.[7]

Indole-3-Acetic Acid (IAA)

  • Indole-3-acetic acid (IAA) is a naturally occurring plant hormone that is also produced by some gut bacteria.[4] Proper levels of IAA maintain beneficial Lactobacillus species of gut bacteria.
  • IAA is a precursor to other important metabolites, like indole-3-propionic acid (IPA).[5,6]
  • Both high and low levels of IAA can indicate a potential dysbiosis (bacterial imbalance), which can lead to a variety of adverse symptoms, including gastrointestinal (GI) distress, inflammation, poor immune system, sleep disturbances, skin inflammation, and negative health outcomes.
Tryptophan

Tryptophan

Serotonin

Serotonin

Kynurenine

Kynurenine

  • Kynurenine (KYN) is a tryptophan metabolite made in the liver.[16] Gut bacteria influence the conversion of tryptophan into kynurenine.[18]
  • Due to kynurenine’s critical role in the body’s inflammatory response, high levels of kynurenine can indicate chronic infection and/or deficiency of vitamin B6, a vitamin important for the creation of red blood cells.[19,21]
  • Beacuse B vitamins influence kynurenine production and metabolism, high or low levels of kynurenine may be due to vitamin B deficiencies.[21]
Indoxyl Sulfate

Indoxyl Sulfate

Tyrosine

Tyrosine

Xanthine

Xanthine

  • Xanthine (XAN) is a metabolite of the purine pathway.[26]
  • In the digestive tract, xanthine induces hydrochloric acid production and promotes secretion of pepsin from cells lining the stomach, which aids in digestion.[28] However, elevated xanthine can lead to oxidative stress and increase risk of inflammation.
  • Elevated xanthine may be the result of caffeine intake, cardiovascular overtraining, and/or physical and emotional stress.[29]
  • Xanthine accumulation during strenuous cardiovascular exercise can limit energy output, in turn affecting performance.
3-Methylxanthine

3-Methylxanthine

Uric Acid (UA)

Uric Acid (UA)

About the Five Areas of Health

Ixcela: Gastrointestinal Fitness

What is Gastrointestinal Fitness?

The gastrointestinal (GI) tract is an organ system comprising the esophagus, stomach, and the large and small intestines. The GI tract is responsible for the swallowing and digestion of food, absorption of nutrients, and generation of waste. The GI tract is also home to trillions of microbes, known as the gut microbiome, which has been found to be vital to GI and systemic health, modulation of the immune system, and regulation of brain function.1–3 GI health and fitness revolves around maintaining the structural integrity of the intestinal wall and maintaining optimal levels of biochemicals and gut microbes. A number of metabolites associated with gut health are measured using the Ixcela Internal Fitness™ test kit, resulting in your Gastrointestinal Fitness score.

Ixcela: Immuno Fitness

What is Immuno Fitness?

The immune system’s response to various physiological perturbations plays a significant role in maintaining optimal internal health. Additionally, research has shown that the relationship between the body’s immune system and the gut microbiome is inter-dependent, with both systems producing compounds that affect each other.1,6–9 A healthy gut improves the body’s ability to fight infection. Growth and development of the gut microbiome over the human lifespan, especially postnatally and through infancy, also influences development of the immune system and vice versa.1,10 Normal levels of antibodies and immune cells, stable gut wall integrity, and lack of food allergies are some characteristics of a healthy immune system. The Immuno Fitness score is a measure of immune health and is modulated by certain key metabolites.

Ixcela: Emotional Balance

What is Emotional Balance?

Emotional well-being is one of the most important factors in the overall health of an individual. The body’s response to stress—physical, physiological, or psychological—is a key determinant in regulation of emotional state,3,14 and studies increasingly support that the gut microbiome is a major contributor to stress response3,14,15 and thus emotional well-being. Through various biochemicals, the gut microbiome has been linked to affecting mood, anxiety, and other conditions modified by stress.3,14-16 Your Emotional Balance score is a measure of emotional health and is modified by the composition of microbes and levels of metabolites in the gut.

Ixcela: Cognitive Acuity

What is Cognitive Acuity?

In the last decade, there has been tremendous research about the complex bidirectional communication between the brain and gut microbiome. Through numerous studies, it has become evident that the gut microbiome regulates, and is itself regulated by, the brain via various hormones and signaling molecules.3,5,14,15 Effects of the gut microbiome on the brain have been linked to certain types of microbial species residing in the gut.3,20 Through mechanisms such as stimulation of the nervous system, production of toxic metabolites, and change in intestinal wall permeability, the gut microbiome influences neurological chemistry and function, enhancing cognitive function.3,5,14–16 Cognitive Acuity is a measure of gut-mediated neurological health.

Ixcela: Energetic Efficiency

What is Energetic Efficiency?

Major functions of the gut are digestion of food and absorption of nutrients, and the gut microbiome plays a critical part in these processes.1,4,11,21 Microbes in the gut synthesize molecules known as short-chain fatty acids from nondigestible dietary components.1,22,23 These molecules act as a source of energy for the body and promote cellular mechanisms that maintain tissue integrity. Additionally, studies have found that harvesting energy from food is a microbial species-dependent process.24,25 Thus, having the right microbes in your gut will improve your daily energy levels. Your Energetic Efficiency score is reflective of the gut microbiome’s ability to effectively harness energy for the body.


*These statements have not been evaluated by the FDA. These products are not intended to diagnose, treat, cure or prevent any disease.


References

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