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SmoothNRG Citrus Flavor - Physician Nutrients
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SmoothNRG Citrus Flavor

$ 49.99

SmoothNRG™ transforms water into a great-tasting, revitalizing energy drink. Each stick provides a combination of B vitamins, electrolytes, trace minerals, amino acids, and antioxidants to fuel your body’s energy production. Building on these important nutrients, SmoothNRG™ also features Purenergy™, a technology-driven, patent-protected ingredient that combines caffeine and pTeroPure® pterostilbene. Initial reports suggest that Purenergy’s™ caffeine may be absorbed more slowly and stay in your system longer than regular caffeine, which may help your energy last longer. With just 5 g of carbohydrate per serving and zero sugars, SmoothNRG™ simply gives your body what it needs to produce energy.*

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.


30 Stick Packs


Designed to Support a Healthy Energy Level*
Supports Electrolyte Replacement*
Helps Fight Free Radicals with Antioxidant Nutrients, Including S-Acetyl-L-Glutathione and 500 mg of Vitamin C*
Provides an Alternative to Ordinary Caffeine*
Provides Ingredients That Support ATP Biosynthesis*

Directions: Dissolve the contents of one stick pack in 6-12 oz of water according to preferred sweetness. You may consume the effervescent drink once daily, or use as directed by your healthcare practitioner.

Consult your healthcare practitioner prior to use. Individuals taking medication should discuss potential interactions with their healthcare practitioner. Caffeine should not be combined with synephrine or ephedrine. Use cautiously if you have a history of abnormal heart rhythm. Do not use if tamper seal is damaged.  Do not use if pregnant, nursing or under 18 years of age.  Product contains caffeine.  Persons sensitive to caffeine should take with caution, starting with partial dose and slowly working up.  Stop using if you experience nervousness, sleep disruption, rapid or irregular heartbeat.

Storage: Keep tightly closed in a cool, dry place out of reach of children.

Does Not Contain: Wheat, gluten, yeast, soy protein, animal or dairy products, fish, shellfish, peanuts, tree nuts, egg, ingredients derived from genetically modified organisms (GMOs), artificial colors, artificial sweeteners, or artificial preservatives.


*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.


Purenergy™ is an innovative patent-protected ingredient that combines caffeine with pTeroPure® pterostilbene—a highly bioavailable analog of resveratrol—to form a unique co-crystal structure. It appears that this unique structure affects the way the body utilizes caffeine. As such, it may offer significant advantages over caffeine alone.*

Study Findings

In a rat study (n=6), the half-life of the caffeine from Purenergy™ was eight hours, while that of ordinary caffeine was just three hours. In a preliminary, four-week, single-blind, crossover human study (n=12) that compared 232 mg of Purenergy™ (providing 99.76 mg of caffeine) to 100 mg of ordinary caffeine, the following effects were demonstrated: 

Purenergy™ delivered almost 30% more caffeine into the blood than ordinary caffeine.*

The absorption rate of the caffeine from Purenergy™ was significantly slower by approximately 30% compared to ordinary caffeine.*

The half-life of the caffeine from Purenergy™ was extended significantly by approximately 25% compared to ordinary caffeine.*

At 4 hours, serum showed 45% more caffeine from Purenergy™ compared to ordinary caffeine.*

At 6 hours, serum showed 51% more caffeine from Purenergy™ compared to ordinary caffeine.*

Purenergy™ had no adverse effect.*

While the results of these studies are promising, larger studies are needed to validate the findings and determine if these findings translate into a lengthened energy effect.*

More Energy

Taken together, data from these studies suggest that the effects of caffeine from Purenergy™ may last longer than the effects from ordinary caffeine and point to a potential for reducing total caffeine intake due to Purenergy’s™ more efficient delivery and slower absorption rate. These are encouraging factors for people who wish to reduce their caffeine intake.*

Slower Caffeine “Finish”

Scientists are researching whether or not the extended half-life and slower absorption rate of caffeine from Purenergy™ can produce a more moderated and gradual finish. This may help prevent the “crash” associated with regular caffeinated energy products and may give SmoothNRG™ an advantage over formulas that use ordinary caffeine.*

All-Natural, No Sugars

SmoothNRG™ relies on natural ingredients, not ephedra or artificial stimulants. Furthermore, it provides only five grams of carbohydrates and zero sugars. By using natural flavors and stevia in place of sugar and other carbohydrates, the typical “sugar high” that is associated with many energy drinks can be avoided. Equally important, SmoothNRG™ contains no artificial colors.*

Caffeine, in General

In animal and human studies, caffeine has demonstrated positive effects on athletic performance, fatigue, and cognitive functions, such as supporting a healthy memory. According to Meeusen et al, research on caffeine suggests its performance-enhancing effect is related to antagonism of the adenosine receptors that influence the dopaminergic and other neurotransmitter systems.*


In the aforementioned human study, Purenergy™ also delivered approximately 50% more total pterostilbene into the blood than pTeroPure® delivered alone, thus potentially enhancing the functional benefits of pterostilbene. Pterostilbene is a highly bioavailable analog of resveratrol—a stilbenoid found in blueberries and grapes. Compared to resveratrol, pterostilbene is four times more bioavailable, has a seven times greater half-life, exhibits greater oral absorption and metabolic stability (pterostilbene is more lipophilic), and produces two to four times greater cellular uptake. Aside from resveratrol’s well-known antioxidant benefits that support cardiovascular health, pterostilbene is also known to activate certain proteins (i.e., SIRT1 and PGC-1α) involved in increasing mitochondrial biogenesis and therefore ATP (energy) production.*

Electrolytes and Antioxidants

Electrolytes—including sodium, potassium, and magnesium—are important for energy production, nerve transmission, musclevcontractions, pH balance, fluid balance, and more. Conditions that promote excessive sweating and increased metabolic activity can require replacement of these important minerals and increase the need for antioxidants. SmoothNRG™ provides 130 mg of sodium, 280 mg of potassium, and 150 mg of magnesium in each serving. To support protection from free radicals, SmoothNRG™ provides 500 mg of vitamin C in the form of four mineral ascorbates, as well as natural vitamin E, selenium, green tea extract, and s-acetyl-L-glutathione (SAG). SAG is an orally stable glutathione that has been shown to cross the membrane of the mitochondria, which increases the organelle’s activity and helps minimize reactive oxygen species.*

Green Tea and Amino Acids

SmoothNRG™ combines Purenergy™ in a proprietary blend and amino acids, including green tea extract, coffee fruit extract, taurine, and L-arginine alpha-ketoglutarate. This proprietary blend is designed to complement the activities of Purenergy.™ Furthermore, some of these individual ingredients taken in high doses have roles in mitochondrial biogenesis or are known to have a positive influence on exercise performance.*

B Vitamins

As essential parts of coenzymes, these water-soluble nutrients are integral to the complex biochemical processes that convert food to glucose and ATP—the energy used by cells. Vitamin B12 also works closely with folate to help make red blood cells and facilitate the work of iron in the body. Iron helps carry oxygen to all cells, including muscle cells, for use in the generation of energy.*


*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

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