What is Px?
Paraxanthine (also called Px) is a natural metabolite of caffeine. All that means is that Px is made in the body when the liver metabolizes, or breaks down, caffeine. In fact, the majority of caffeine in our bodies is converted to Px.
It can also be found in very small amounts in some foods, including coffee beans, Theobroma cacao fruits, citrus flowers, and Sicilian orange flower honey.
Like caffeine, Px increases alertness, reduces fatigue, and decreases drowsiness. However, Px is less likely than caffeine to cause negative side effects, including “jitters”, anxiety, irritability, and nervousness.
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Benefits by the bean
Recent studies (both by us and by independent researchers) on paraxanthine have explored many potential benefits of Px:
Ingredient List
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Sleep
In mice, Px showed no evidence of sleep rebound (debt) compared to caffeine, while providing the same amount of wakefulness at equimolar concentrations.
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Energy & Endurance
In some studies, Px has been shown to boost nitric oxide production, leading to increased treadmill endurance, grip strength, and muscle mass.
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Focus
Px has been shown to have cognitive performance benefits and may even help to preserve dopaminergic neurons, helping to protect against age-related cognitive decline.
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Anxiety
In animal and clinical studies, caffeine is anxiogenic (anxiety increasing). In contrast, Px has been shown to exhibit anxiolytic (anxiety decreasing) properties.
Other reported benefits
While we have not specifically performed dedicated clinical trials for these benefits, many of our users share their experiences with us which include other possible benefits¹ including:
Ingredient List
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Blood Pressure
"Other brands I’ve tried increase my blood pressure because of the caffeine content. But since I’ve been drinking this brand of coffee, my pressure went down."
-Bola A.
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Blood Glucose
"...caffeine always, always spikes my blood sugar. But for the last two weeks... most my graphs have looked like this, without the blood sugar spike."
-Tini
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Heart health
Support your heart and the formation and maintenance of red blood cells.
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Enduring energy
AG1 provides nutrients that make sure energy gets to where you really need it.
¹ These statements are informational and not medical advice, intended only to share what we've received as feedback from our users.
Is Px Safe?
Paraxanthine has GRAS (Generally Regarded As Safe) status and as compared to caffeine, has a higher oral LD50 (829-1601 mg/kg vs. 127-367 mg/kg for caffeine; rodent) and NOAEL (no adverse effect level)—185-300 mg/kg vs. 150 mg/kg.
Additionally, Px has been shown to have a shorter half-life (3.1 hours) than caffeine (4.1h) and the other major caffeine metabolites, theobromine (7.2h) and theophylline (6.2h), meaning it is processed and cleared from the body faster, so it is less likely to negatively affect sleep quality.
Both paraxanthine and caffeine are CNS stimulants. As such, Px is not intended for use by children and you should consult your physician if you are pregnant, lactating, have a medical condition, or are taking any medications.
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The energy-boosting effects of caffeine come from it's ability to inhibit Adenosine receptors A1 and A2A.
We measured Px and caffeine head-to-head, and the results speak for themselves: Px is up to 2.7x (A1) and 3.5x (A2A) more effective than caffeine.
This means Px has the ability to provide all the focus, energy, and performance of caffeine—but without the jitters, anxiety, and impact on sleep quality.
EFFICACY
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A LITTLE BIT ABOUT US
At Rarebird, we're bringing metabolic science to everyday real-world issues. We developed Px Coffee to give coffee drinkers all of the focus, energy and performance boost without the stress, anxiety and jitters.