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Synedrex Review – Metabolic Nutrition – Side Effects, Ingredients & More

Expert opinion:

Not Recommended


What is Synedrex—diet pills, or something else entirely? That’s the question many people are asking themselves this year, after hearing about this thermogenic agent for the first time. Synedrex by Metabolic Nutrition is a purported “one pill solution” that uses caffeine and other ingredients to provide energy, suppress the appetite, accelerate weight loss, enhance mental focus, and improve mood in those who take it. The product’s website also claims that the special proprietary blend in Synedrex allows users to avoid the crash common to other stimulants and weight loss products.1

Thanks to increasing attention surrounding this product, more and more users are looking for evidence to support the claims made by Metabolic Nutrition. Synedrex reviews like this one may help users decide if this product is right for their fitness goals. So, can this thermogenic weight loss supplement deliver results? In our unbiased Synedrex review, we examine each of the ingredients in the Synedrex original formula to determine their likely effectiveness and provide additional details on the safety of thermogenic weight loss products so that you can make an informed decision.

Synedrex reviews
Synedrex ingredients per serving of Synedrex diet pills

Ingredients in Synedrex are combined in a proprietary Synedrex weight loss blend to ensure their formula is not replicated by competitors.

Synedrex Ingredients

The Synedrex Metabolic Nutrition formula uses a combination of stimulants, natural herbal extracts and alkaloids to create a unique blend designed to increase energy and burn fat. Ingredients in Synedrex are combined in a proprietary blend, which does not indicate the individual dose used for each ingredient. Below, we take a look at the latest science behind these diverse ingredients.

Caffeine Anhydrous— Caffeine anhydrous is a highly-concentrated caffeine powder that is routinely used in many stimulants to enhance performance, boost energy, temporarily boost metabolism and improve endurance.2

2-Aminoisoheptane — 2-Aminoisoheptane is another stimulant that has recently re-emerged on the supplement scene. It’s believed to have sympathomimetic (stimulating the sympathetic nerves) properties that have been associated with higher energy levels and suppression of the appetite.15

Eria Jarensis Extract— Eria jarensis is a natural herbal extract derived from certain species of orchids. Also known as N-Phenethyl Dimethylamine, it’s said to have therapeutic mood-boosting properties.3

In clinical trials, higenamine has been shown to stimulate increased energy expenditure and lipolysis (breakdown of fats).7

Grains of Paradise— Commonly used in culinary dishes as a substitute for pepper, grains of paradise seeds are also used in several thermogenic weight loss supplements to designed to control whole body energy-expenditure and body fat content.4

Bitter Orange Extract— Bitter orange is a natural substance used in a wide range of dietary supplements to control weight and boost athletic performance.5

Yohimbine HCI— Yohimbine hydrochloride (HCI) is a form of yohimbine, which is derived from a certain form of tree bark and which has been examined for antidepressant properties.6

Higenamine (Norcoclaurine)— A part of the Nandina plant, higenamine is an herbal extract that is commonly used as a fat burner.7

Hordenine— Found in grains such as barley and certain grasses, hordenine is an alkaloid that is widely used in supplements to promote energy, support appetite control and facilitate fat loss.8

Huperzine A— Derived from Traditional Chinese Medicine (TCM), huperzine a is an alkaloid that is widely associated with cognitive enhancement.9

Naringin— A natural antioxidant, naringin is often used for the purposes of lowering cholesterol.10

Did you Know: Metabolic Nutrition, the company behind Synedrex has been manufacturing supplements for athletes for over 25 years.

N-Methylphenethylamine — N-Methylphenethylamine is an alkaloid used for weight loss support and increased athletic performance.11

L-Dopa—Laevodihydroxyphenylalanine (L-DOPA) is an amino acid that occurs naturally in the human body. It is sometimes used in supplements to increase dopamine levels.12

Poly-Thyronine— Thyronines are amino acids that have been associated with reducing symptoms of fatty liver in clinical trials.13

How to Take Synedrex

Synedrex recommends taking a single capsule in the morning with food at first, in order to assess tolerance. Users are advised not to take more than one capsule per day, and to avoid taking Synedrex fat burner within 12 hours of going to bed. It is also recommended that users drink water liberally while taking Synedrex, since Metabolic Nutrition claims that proper hydration will improve results.1 Since it is common knowledge that products with caffeine should not be mixed with alcoholic beverages, Synedrex and alcohol should not be taken together.

Synedrex Side Effects

The Synedrex website encourages each user to assess their tolerance when using the product for the first time so as to prevent over-stimulation, which is a potential side effect of most stimulants.1 Caffeine may cause mild side effects such as jitteriness, stomach cramping or increased nervousness.  It also mentions that taking Synedrex on an empty stomach can cause feelings of nausea.

Unlike Synedrex, banned supplements have pervious used ephedrine alkaloids, which have been proven to be dangerous as they carry a risks of illness and injury.14 However, Synedrex uses other alkaloids that are low risk and have not been banned by the FDA. A 60-day double-blind placebo-controlled study on the use of bitter orange extract with naringin showed no adverse effects at a dose of up to 98mg daily for 60 days at the measured parameters.5

Metabolic Nutrition also recommends reading the entire label to make sure that individual users are not allergic or intolerant to specific ingredients.1

Synedrex Results

For those of you wondering about potential Synedrex results, before and after comparisons from Synedrex customer reviews suggest that the product can be effective when combined with a healthy lifestyle including regular exercise.1 There is also compelling scientific evidence to suggest that several of the ingredients in Synedrex may support the stated goals of the product.

Of the many ingredients in Synedrex, caffeine is likely one of the most active. Studies show that caffeine is a reliable stimulant for increasing performance when taken before periods of high-intensity exercise.2

In a 2013 study, supplementing with grains of paradise extract was shown to significant increase whole body energy expenditure by activating brown adipose tissue in healthy male subjects.4

Supplements containing yohimbine and hordenine have also been shown to increase performance as well as feelings of energy and focus in male athletes in clinical studies.8 This could account for the claim that Synedrex helps users avoid caffeine “crashes”.Of the many ingredients in Synedrex, caffeine is likely one of the most active. Studies show that caffeine is a reliable stimulant for increasing performance when taken before periods of high-intensity exercise.2

Synedrex weight loss results may vary from one individual to another. However, there is sufficient evidence supporting many of the ingredients in Synedrex pills to suggest that it can be an effective energy and performance supplement in certain individuals.

Synedrex Reviews

Reviews on Synedrex tend to be positive, with some users sharing before and after photos of their results. Something most customers tend to agree on is that the product is extremely portable and easy to use – as mixing powder supplements can get messy and tedious. Several customers also confirmed that Synedrex did not cause a caffeine crash, which can happen with similar supplements.

Where is Synedrex for Sale (GNC or Online?)

For readers wondering where to buy Synedrex, GNC and other popular supplement retailers currently do not carry Synedrex in stores or online. You can buy Synedrex online in the USA and Puerto Rico by going directly to the product’s website. For customers living in Canada and abroad, online third-party retailers such as Amazon may offer this product.

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Scientific Research Referenced in this Article

  1. (n.d.) Retrieved November 06, 2017, from – View Reference
  2. Trexler E., et al. (2015). Effects of coffee and caffeine anhydrous on strength and sprint performance. European Journal of Sport Science, 16(6) 702-710. Doi: http://dx.doi.org/10.1080/17461391.2015.1085097
  3. Pluskal T. and Weng J. (2017). Natural product modulators of human sensations and mood: molecular mechanisms and therapeutic potential. Chemical Society Reviews. Advance Article. Doi: 1039/C7CS00411G
  4. Sugita J., et al. (2013). Grains of paradise (Aframomum melegueta) extract activates brown adipose tissue and increases whole-body energy expenditure in men. British Journal of Nutrition, 110(4) 733-738. Doi: https://doi.org/10.1017/S0007114512005715
  5. Kaats G. R., et al. (2013). A 60 day double-blind, placebo-controlled safety study involving Citrus aurantium (bitter orange) extract. Food and Chemical Toxicology, 55. Doi: https://doi.org/10.1016/j.fct.2013.01.013
  6. Papeschi R., Sourkes, T.L. and Youdim M.B.H. (1971). The effect of yohimbine on brain serotonin metabolism, motor behavior and body temperature of the rat. European Journal of Pharmacology, 15(3) 318-326. Doi: https://doi.org/10.1016/0014-2999(71)90098-7
  7. Lee S., et al. (2013). Acute oral intake of a higenamine-based dietary supplement increases circulating free fatty acids and energy expenditure in human subjects. Lipids in Health and Disease, 12:148 Doi: https://doi.org/10.1186/1476-511X-12-148
  8. Hoffman J.R., et al. (2009). Examination of a pre-exercise, high energy supplement on exercise performance. Journal of the International Society of Sports Nutrition, 6:2. Doi: https://doi.org/10.1186/1550-2783-6-2
  9. Ma X., et al. (2007). Huperzine A from Huperzia species—An ethnopharmacolgical review. Journal of Ethnopharmacology, 113(1) 15-34. Doi: https://doi.org/10.1016/j.jep.2007.05.030
  10. Jeon S., et al. (2001). Antioxidative activity of naringin and lovastatin in high cholesterol-fed rabbits. Life Sciences, 24(2) 2855-2866. Doi: https://doi.org/10.1016/S0024-3205(01)01363-7
  11. Liu Y. and Santillo M.F. (2015). Cytochrome P450 2D6 and 3A4 enzyme inhibition by amine stimulants in dietary supplements. Drug Testing and Analysis, 8(3-4) 307-310. Doi: 1002/dta.1863
  12. Foster H.D. and Hoffer A. (2004). The two faces of L-DOPA: benefits and adverse side effects in the treatment of Encephalitis lethargica, Parkinson’s disease, multiple sclerosis and amyotrophic lateral sclerosis. Medical Hypotheses, 62(2) 177-181. Doi: https://doi.org/10.1016/S0306-9877(03)00318-9
  13. Mollica M.P., et al. (2009). 3,5-diiodo-l-thyronine, by modulating mitochondrial functions, reverses hepatic fat accumulation in rats fed a high-fat diet. Journal of Hepatology. 51(2) 363-370. https://doi.org/10.1016/j.jhep.2009.03.023
  14. S. Department of Health and Human Services. (2004). Ephedra. Retrieved November 06 2017, from https://ods.od.nih.gov/Health_Information/Ephedra.aspx
  15. Al-Imam, A., & AbdulMajeed, B. A. (2017). Captagon, Octodrine, and NBOMe: An Integrative Analysis of Trends Databases, the Deep Web, and the Darknet. Global Journal of Health Science9(11), 114. https://doi.org/10.5539/gjhs.v9n11p114

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