The CAR Decline Response is a significant indicator of the hypothalamic-pituitary-adrenal (HPA) axis functionality and reflects the body's response to stress. Cortisol, a glucocorticoid hormone produced by the adrenal cortex, plays a crucial role in various physiological processes, including metabolism regulation, immune response modulation, and stress response. Upon waking, cortisol levels typically surge, peaking within the first 30 to 45 minutes, and then gradually decline throughout the day, following a diurnal rhythm. This initial spike, or the CAR, is thought to be associated with the anticipation of the upcoming day's challenges and is influenced by various factors such as sleep quality, psychosocial stressors, and underlying health conditions.

The "CAR (Cortisol Awakening Response) Rise Response" is a physiological phenomenon observed in the hypothalamic-pituitary-adrenal (HPA) axis, reflecting the body's reaction to stress and its regulatory mechanisms of stress hormones, primarily cortisol.

Upon awakening, a marked increase in cortisol levels is typically observed, peaking within the first 30 to 45 minutes after waking. This response is thought to be an adaptive mechanism that prepares the body for the anticipated demands of the day, enhancing alertness and mobilizing energy resources. The magnitude and pattern of the CAR can be influenced by various factors, including sleep quality, psychosocial stressors, and underlying health conditions. Scientific studies have utilized the CAR as a biomarker for assessing HPA axis function and its dysregulation in stress-related disorders, such as chronic fatigue syndrome, depression, and post-traumatic stress disorder (PTSD).

Simple sugars are absorbed in the small intestine and should not be appreciably present in the colon because they are a primary energy source for pathogenic or dysbiotic bacteria and yeast.

Carbon dioxide (CO₂) is a natural byproduct of metabolism. In the bloodstream, most CO₂ exists as bicarbonate (HCO₃⁻)—a key buffer that helps regulate the body’s acid–base (pH) balance. Maintaining this balance is essential for normal cellular function, enzyme activity, and overall metabolic stability.

A CO₂ blood test—commonly included in a Basic Metabolic Panel (BMP) or Comprehensive Metabolic Panel (CMP)—primarily measures bicarbonate levels. It provides insight into the body’s acid–base status and electrolyte balance and can help identify disturbances related to kidney function, lung function, hydration status, or metabolic health.

Low CO₂ levels may be associated with metabolic acidosis, kidney disease, severe diarrhea, uncontrolled diabetes, or prolonged hyperventilation. Elevated CO₂ levels may reflect metabolic alkalosis, dehydration, chronic lung disease (such as COPD), or impaired ventilation.

CO₂ results are interpreted alongside related markers—such as sodium, potassium, chloride, and blood pH—to understand the underlying cause. Adult reference ranges typically fall between 20–29 mEq/L, though ranges vary by lab. Mild abnormalities are not always clinically significant and may be influenced by medications, diet, hydration, or temporary illness. Your healthcare provider will interpret results in the context of your full clinical picture.

Determine the extent of carbon monoxide poisoning, toxicity; check on the effect of smoking on the patient; work up headache, irritability, nausea, vomiting, vertigo, dyspnea, collapse, coma, convulsions; work up persons exposed to fires and smoke inhalation.

Carbon monoxide levels are of limited value in testing for smoking, since it is cleared rapidly. The half-life of carboxyhemoglobin in individuals with normal cardiopulmonary function is one to two hours. Urinary cotinine, if available, is preferable as a test for tobacco use. Arterial blood gases may be of limited value in treatment decisions for carbon monoxide poisoning.

Carboxyhemoglobin is useful in judging the extent of carbon monoxide toxicity and in considering the effect of smoking on the patient. A direct correlation has been claimed between CO level and symptoms of atherosclerotic diseases, intermittent claudication, angina, and myocardial infarction. Exposure may occur not only from smoking but also from garage exposure, and from various motors.

The novel antibodies salivary gland protein 1 (SP-1), carbonic anhydrase 6 (CA VI) and parotid secretory protein (PSP) have shown to be present in animal models for Sjogren's syndrome (SS) and patients with the disease. The antibodies SP-1, CA VI and PSP occurred earlier in the course of the disease than antibodies to Ro or La.

The novel antibodies salivary gland protein 1 (SP-1), carbonic anhydrase 6 (CA VI) and parotid secretory protein (PSP) have shown to be present in animal models for Sjogren's syndrome (SS) and patients with the disease. The antibodies SP-1, CA VI and PSP occurred earlier in the course of the disease than antibodies to Ro or La.

The novel antibodies salivary gland protein 1 (SP-1), carbonic anhydrase 6 (CA VI) and parotid secretory protein (PSP) have shown to be present in animal models for Sjogren's syndrome (SS) and patients with the disease. The antibodies SP-1, CA VI and PSP occurred earlier in the course of the disease than antibodies to Ro or La.

Carboxycitric is a metabolite of yeast/fungi and general indicator of gastrointestinal dysbiosis. Elevated yeast/fungal metabolites indicate overgrowth in the GI tract.

Carboxycitric is a metabolite of yeast/fungi and general indicator of gastrointestinal dysbiosis. Elevated yeast/fungal metabolites indicate overgrowth in the GI tract.

Carboxycitric acid, an analogue of the Krebs/citric acid cycle, serves as a marker for intestinal microbial overgrowth, particularly involving yeast and fungi. As a byproduct of the Krebs cycle, elevated levels may also point to energy metabolism disorders. Research has shown that children with autism tend to have lower levels of 3-oxoglutaric acid, which is thought to result from increased uptake of these compounds across the blood-brain barrier. Urinary levels of carboxycitric acid have been observed to decrease following nystatin therapy. To identify the root cause, consider testing with a Gut Zoomer, fungal antibodies, or a mycotoxin panel. Implementing multi-strain probiotics and comprehensive gastrointestinal support can help improve this condition.

Carboxyhemoglobin is a form of hemoglobin that develops when carbon monoxide (CO) binds to red blood cells. Carbon monoxide has a much stronger affinity for hemoglobin than oxygen does—over 200 times stronger—so even modest exposure can reduce the body’s ability to carry oxygen. This test measures the percentage of total hemoglobin bound to carbon monoxide and is used to evaluate oxygen-carrying capacity, detect carbon monoxide exposure, and assess smoking status or environmental/occupational risks.

A carboxyhemoglobin level above 2% but below 5% is typically seen in individuals who are exposed to low levels of carbon monoxide, most commonly light or moderate smokers or people who are regularly around secondhand smoke or mild environmental CO sources. While this range is above the normal nonsmoker reference (<2%), it is not generally considered dangerous on its own. However, it does indicate that the body’s oxygen-carrying capacity is slightly reduced, which may contribute to symptoms like mild headaches, fatigue, or decreased exercise tolerance in sensitive individuals. For those who do not smoke, a result in this range may prompt evaluation for hidden carbon monoxide exposure, such as from poor indoor ventilation, gas appliances, garage exhaust, or occupational settings. Reducing environmental CO exposure, improving ventilation, and avoiding smoke can help bring levels back into the nonsmoker range.

Carcinoembryonic Antigen (CEA) is a blood test used primarily to monitor certain cancers — especially colorectal cancer. It is not used to diagnose cancer or screen healthy individuals. Instead, CEA is most useful for tracking treatment response and detecting cancer recurrence over time. Elevated levels can occur in cancer, but also in non-cancer conditions such as liver disease, inflammatory bowel disease, smoking, and chronic lung disease. Because of this, CEA must always be interpreted alongside imaging and clinical history — and trends over time are far more important than a single result.

A low CEA level (within the reference range) generally indicates no active tumor marker elevation.

However:

• Not all cancers produce CEA

• Normal results do not rule out cancer

• Continued monitoring may still be required in high-risk patients

- Anticardiolipins are antibodies produced by the immune system against the platelet membrane phospholipids responsible for the coagulation of blood clots. 

- Anticardiolipin antibodies are often responsible (with lupus anticoagulants and beta-2 glycoprotein antibodies) for the abnormal formation of clots in veins (phlebitis) and arteries (arterial thrombosis). 

- They are involved in antiphospholipid syndrome, which occurs, for example, through repeated miscarriages during the second or third trimester of pregnancy. 

There are three types of anticardiolipin antibodies: IgG, IgA and IgM.

- Anticardiolipins are antibodies produced by the immune system against the platelet membrane phospholipids responsible for the coagulation of blood clots. 

- Anticardiolipin antibodies are often responsible (with lupus anticoagulants and beta-2 glycoprotein antibodies) for the abnormal formation of clots in veins (phlebitis) and arteries (arterial thrombosis). 

- They are involved in antiphospholipid syndrome, which occurs, for example, through repeated miscarriages during the second or third trimester of pregnancy. 

There are three types of anticardiolipin antibodies: IgG, IgA and IgM.

- Anticardiolipins are antibodies produced by the immune system against the platelet membrane phospholipids responsible for the coagulation of blood clots. 

- Anticardiolipin antibodies are often responsible (with lupus anticoagulants and beta-2 glycoprotein antibodies) for the abnormal formation of clots in veins (phlebitis) and arteries (arterial thrombosis). 

- They are involved in antiphospholipid syndrome, which occurs, for example, through repeated miscarriages during the second or third trimester of pregnancy. 

There are three types of anticardiolipin antibodies: IgG, IgA and IgM.