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Customers are raving about FENFAST 375. This high-quality nutraceutical is our TOP SELLING diet support product that also contains researched energy enhancers to produce a POWERFUL FORMULA THAT MAKES HEALTHY DIETING EASIER – IT'S THAT SIMPLE!*

FENFAST 375 White & Blue Speck Tablets will help you to get control over even the most difficult aspects of dieting. FENFAST 375 gives you the diet power you need to succeed by providing clinically researched and tested ingredients to make a healthy diet and consistent exercise much easier to maintain.*
  • TOP-RATED DIETING SUPPORT – take control over your hunger.*
  • THERMOGENIC BOOSTERS – support your body's ability to burn fat.*
  • METABOLISM ENHANCERS – have your body running at its best levels.*
  • INCREASED ENERGY – so you’ll power through every busy day and still have energy.*
  • DIETING IN A HEALTHY & EFFECTIVE WAY – so that you’ll get it off and keep it off.
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  • 1 Bottle
  • 2 Bottle

    SAVINGS $4.00

  • 3 Bottle

    Most Popular


    SAVINGS $10.00

  • 6 Bottle

    Best Deal


    SAVINGS $45.00

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How Does FENFAST 375 Work?

FENFAST 375 diet pills combine powerful thermogenics with clinically-studied diet support ingredients. Backed by hundreds of 5-Star customer reviews, FENFAST 375 is a top-selling diet pill that improves energy and focus to support a successful weight loss strategy.

FENFAST 375 is manufactured in the USA with the highest quality, premium-grade ingredients that have been combined into an easy-to-swallow, white & blue speck tablet. It was engineered to use only the best combination of ingredients that have been tested through clinical study to complement a healthy diet program. FENFAST 375 has been a part of the lives of THOUSANDS of dieters who have reached a healthier weight and the proof is with their satisfaction – our customers leave the BEST REVIEWS!

Because of the design and formulation of FENFAST 375, adults of all ages, shapes and sizes are able to use it as a part of a healthy diet plan that will help them to finally achieve a leaner body. FENFAST 375 achieves this with its formulation of 100% scientifically-studied ingredients that include: L-Phenylalanine, Caffeine, L-Theanine and Theobromine.

The ingredients in FENFAST 375 work synergistically, amplifying each of their benefits and providing the ULTIMATE in DIET SUPPORT & ENERGY ENHANCEMENT for the BEST DIET SUCCESS*.

The ingredients in FENFAST 375 work synergistically, amplifying each of their benefits and providing the ULTIMATE in DIET SUPPORT & ENERGY ENHANCEMENT for the BEST DIET SUCCESS*.


  • PROMOTE HEALTHIER EATING* One of the most difficult aspects of losing weight is sticking to a reduced calorie diet plan containing healthy foods. This is where most dieters struggle and fail. However, when you take FENFAST 375, you take advantage of ingredients that have been shown to banish fatigue and improve focus, which are two major reasons dieters turn to unhealthy foods. With fatigue eliminated and greater focus to eat healthfully, dieting becomes less of a challenge. In fact, customers leave reviews for this product saying they have to remind themselves to eat during the day because their appetites are so diminished. FENFAST 375 diet pills can play an important role in the reduction of calories you consume each day, which can result in fast and noticeable results when combined with a regular exercise routine.*
  • PROVEN METABOLISM ENHANCERS* – Do you feel like no matter what you do, the weight just doesn’t come off? If you do, you are not alone. A slow-running metabolism can hinder even your best dieting efforts, but FENFAST 375 can help you to change all that. The use of industry-leading thermogenic ingredients can help your metabolism work faster, particularly during workouts, but even when you are at rest. One of these ingredients is Caffeine. Multiple studies conducted on caffeine have found it to significantly boost metabolic rate and fat oxidation when compared to placebo.*
  • IMMEDIATE ENERGY RELEASE* – FENFAST 375’s energy-promoting formula will extinguish those sluggish feelings you have during the day and replace them with ENERGY, IMPROVED CONCENTRATION & FOCUS. Not only will this help you to feel great and be more productive during the day even though you are eating less, but it will also give you the energy and motivation you need to keep up a more active lifestyle, which is essential for losing weight. Intensify your workouts and watch your body rapidly transform!*


FENFAST Supports Results:

Mary Lost 28 Pounds!*
Mary Lost 28 Pounds & 10 Inches with FENFAST 375 from Intechra Health*
“I started fenfast in May, so I’ve been on this product for 6 months. I of course, am one of those moms that wanted to lose the baby weight and needed help with the jump start. My starting weight was 173. I am down to 145. My waist was 44 inches and it is now 33.5 inches. This is a huge accomplishment for me. See results above. The picture on the left was taken in June 2013 at my son’s 1st birthday. The picture on the right was taken today.”* ~Mary Sanders

FENFAST® 375 – How Its Ingredients Support Healthy Dieting

This product’s reviews speak for themselves! As our top-rated diet support formula, FENFAST 375 diet pills provide game-changing benefits by using some of the most powerful ingredients currently available in the non-prescription marketplace.

Unlike other diet products that use potentially dangerous ingredients, such as Synephrine and Ephedra, FENFAST® 375 has a powerful and effective formulation that is not associated with the same adverse side effects. FENFAST 375’s formula is based on clinically-researched stimulant ingredients that have been extensively studied in order to best understand their abilities and functions.

The FENFAST 375 dietary supplement is designed to help you overcome the challenges associated with a healthy, reduced calorie diet and daily exercise routine. It is not meant to cause fat to simply melt away on its own. NO product…prescription or not, can do that. (If these claims are made, run the other way!) Instead, this scientifically developed formula works as a tool to be used with an overall healthy, diet program. Whether you have a large amount of weight to lose, or you just want to drop a few pounds for a special occasion, FENFAST 375 is a great choice.

The Science Behind the FENFAST® 375 Formula


L-Phenylalanine is an essential amino acid, which is a building block of protein. In fact, it is the only form of the three types of phenylalanine that is found in protein. Natural sources of this ingredient include milk, meat, fish and eggs, among others. This ingredient is a valuable part of the FENFAST 375 diet pills formula.

This ingredient has been found in reputable scientific study* to provide a significant benefit. This is the release of cholecystokinin (CCK). It is linked with reduction of food intake in humans. Reduced food consumption can offer dieters considerable advantage when they have been struggling to lose excess weight through diet and exercise alone.

In this research, it was shown that when L-phenylalanine was used with human subjects, there was a marked decrease to the amount they were eating every day. When dieters combine reduced food consumption with the right eating choices, it can help them to better achieve their weight loss goal

To dieters, it can mean that they will be able to build better eating habits while overcoming some of the biggest struggles associated with that effort.

.* A B Ballinger and M L Clark. “l-Phenylalanine releases cholecystokinin (CCK) and is associated with reduced food intake in humans: Evidence for a physiological role of CCK in control of eating”. Metabolism. June 1994:Volume 43, Issue 6, Pages 735–738.


An important ingredient in the FENFAST formula is caffeine. This is a well known ingredient throughout the dietary supplement industry, and is highly recognized for its ability to boost energy levels and increase the body’s ability to burn fat as a fuel. These types of effects can make weight management much easier for a dieter to accomplish.

Caffeine functions by producing reactions in the body that help a dieter to overcome some of the primary challenges that they face when they are struggling to meet their weight goals. Clinical study* has indicated that when caffeine is used in appropriate amounts, dieters can experience larger fat mass reductions, reduce their waistlines, and decrease their overall weight than dieters who don’t use it or who use it in amounts that are too low.

Research has also indicated that when using caffeine properly – such as within a high quality formulation that uses the ingredient in the ideal amounts – it can cause a process called thermogenesis to occur (where body heat rises and more fat is burned in order to provide the fuel for the increased temperature). It can also encourage fat oxidation and leptin suppression, for further weight loss benefits.

Of course, caffeine is also very well known for its energy boosting effects as well as helping to

Margriet S. Westerterp-Plantenga, Manuela P.G.M. Lejeune, Eva M. R. Kovacs. Obesity Research. “Body Weight Loss and Weight Maintenance in Relation to Habitual Caffeine Intake and Green Tea Supplementation”.Volume13,Issue7,pages1195–1204,July 2005.


L-theanine is an amino acid that is a natural component of tea. On its own, its benefits in the pursuit of weight loss results are limited, but when combined with caffeine, another ingredient in the FENFAST 375 formula, it has been shown to provide considerable support that dieters can enjoy. It is in this combination that the true strengths of the ingredient come out to shine.

In one study, it was determined that when caffeine and L-theanine were combined, the benefits of these ingredients were amplified. While the stimulant part of caffeine was still able to reduce “mental fatigue” and increase accuracy,memory and reaction time, the subjects were also found to be able to experience the benefits associated with caffeine, but with a reduction in the common side effects, such as headaches.*

Unlike other diet pills that use caffeine alone, the clever addition of this ingredient means that the chances of experiencing side effects associated with that stimulant are measurably reduced.

In another study, caffeine and L-theanine were combined and were found cause a suppression of fat accumulation and improved body weight control. It was also determined that they provided other anti-obesity activities, when combined within the body. **

Together, these ingredients form a powerful fat stopping, anti-obesity and energy boosting combination.

* Haskell, C.F., Kennedy, D.O, et al. Biological Psychology. “The effects of l-theanine, caffeine and their combination on cognition and mood”. Volume 7, Issue 2, February 2008. Pages 113-122.

** Zheng, G., Sayama, K., et al. International Journal of Experimental and Clinical Pathophysiology and Drug Research. “Anti-obesity Effects of Three Major Components of Green Tea, Catechins, Caffeine and Theanine, in Mice”.


Theobromine is a bitter alkaloid extracted from the cacao plant, which is the same source used for producing chocolate. It is also found in other natural food sources such as in tea leaves as well as kola nut.

This ingredient used to be known as xantheose but is now consistently known under its newer name. It should be pointed out that despite the way the name sounds, there isn’t any bromine contained within this substance. Instead, it is a xanthine alkaloid which isn’t entirely unlike caffeine when you examine it on a chemical level. It has been shown to have a stimulant effect but is different from caffeine in certain ways, too.

Theobromine is sometimes included in weight loss dieting support supplements due to the clinical research conducted on it. These include products that are developed for use in conjunction with healthy calorie-controlled dieting as well as regular fitness-appropriate physical activity.

One study* that examined theobromine showed that when using this ingredient in the form of a supplement, it can help to boost energy levels and may also suppress the appetite, as has been shown in certain caffeine studies. At the same time, it indicated that when compared to using a placebo, combining theobromine with caffeine can help to enhance its stimulant effects.

Other research** published in the Psychopharmacology journal compared the effects of caffeine and theobromine and found that while they both had stimulant effects, they did so at different doses. That research concluded that when taken within normal intake ranges, it may be credited with “the positive effects of chocolate.” It determined that “main mechanisms of action are inhibition of phosphodiesterases and blockade of adenosine receptors.” Moreover, it also decided that while unsafe for pets, “theobromine is safe for humans and has fewer unwanted effects than caffeine.”

This was a similar conclusion to a third study*** published in the Frontiers in Pharmacology medical journal, which stated in its conclusion that “theobromine could be considered a safe and natural alternative in the treatment of some human diseases and may serve as lead compound for the development of novel drugs.”

* Mumford, G., Evans, S., Kaminski, B., Preston, K, Sannerud, C., Silverman, K., Griffiths, R. “Discriminative stimulus and subjective effects of theobromine and caffeine in humans”. Phychopharmacology. June 1994. Volume 115, Issue 1-2, pages 1-8.

**Baggott, M.J., Childs, E., Hart, A.B., de Bruin, E., Palmer, A.A., Wilkinson, J.E., de Wit, H. “Psychopharmacology of theobromine in healthy volunteers”. Psychopharmacology. February 2013. Volume 228, Issue 1, pages 109-118.

*** Martínez-Pinilla, E., Oñatibia-Astibia, A., Franco, R. “The relevance of theobromine for the beneficial effects of cocoa consumption”. Frontiers in Pharmacology. February 2015. Volume 6, Issue 30.

FENFAST 375 Supplement Facts & Cautions

What is FENFAST® 375?

FENFAST 375 is dietary supplement. It is sold as white with blue specks tablets with a FENFAST punch on one side. The ingredients in FENFAST 375 are: L-Phenylalanine, Caffeine, L-Theanine and Theobromine.

How to Take FENFAST® 375?

As a dietary supplement, take two (2) tablets of FENFAST® 375 with 8oz of water 2 times daily, approximately 30 minutes before meals. This product is intended to be used along with a calorie-reduced diet and regular exercise program. Do not take within 5 hours of sleep.

What do I do if I miss a dose?

If you miss a dose, take the next as recommended. Do not double the next dose.

What should I know before taking FENFAST 375?

READ ENTIRE LABEL PRIOR TO USE. This product is not intended for pregnant or nursing mothers, women trying to become pregnant, children under the age of 18, or individuals taking prescription drugs. Consult a Physician before using this product if you have, or have a family history of, including but not limited to Phenylketonuria, high blood pressure, cardiac arrhythmias, heart, liver, kidney, thyroid, or psychiatric disease, pheochromocytoma, diabetes, asthma, recurrent headaches, anemia, nervousness, anxiety, depression or other psychiatric condition, peptic ulcers, Parkinson’s disease, glaucoma, difficulty in urinating, prostate enlargement, or seizure disorder, or if you are using any other dietary supplement or over-the-counter drug containing ephedrine, pseudo- ephedrine, or phenylpropanolamine (ingredients found in certain allergy, asthma, cough or cold, and weight control products). Do not use this product if you are using a monoamine oxidase inhibitor (MAOI), anticoagulant or antiplatelet medications, or any other prescription drug. Discontinue use and call a physician or licensed qualified health care professional immediately if you experience rapid heartbeat, dizziness, severe headache, shortness of breath, or other similar symptoms. Individuals who consume caffeine with this product may experience serious adverse health effects and those that are sensitive to the effects of caffeine should consult a Physician before consuming this product. Improper use of this product may be hazardous to a person’s health. Do not exceed the recommended dose. KEEP OUT OF THE REACH OF CHILDREN.

What are the potential side effects from taking FENFAST 375

When taken as directed, there should not be any severe side effects. Some people who are sensitive to stimulants may become excited and/or jittery or experience mild headaches. As with any product, there is always the possibility of an allergic reaction to one of the ingredients. If you have any unusual symptoms when taking this product, discontinue its use right away. If symptoms are severe, please seek medical attention.

*Some customers have received compensation in exchange for their honest review regarding their experience with a product. Results in customer reviews may be atypical and results will vary on individual circumstances. We recommend all products be used with a healthy diet & exercise.