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Do you know about the plant substance synephrine, which is supposed to help you lose weight and melt away fats? Would you like to know more about how it works, how to take it and the scientific evidence? Then we can help you with our article.

In our big Synephrine test 2021 we will provide you with all the important information about Synephrine. You will learn why the natural plant substance is supposed to help with weight loss and why it can boost fat burning.




The most important

  • It has not been scientifically proven that synephrine can help you lose weight. However, its influence on the cardiovascular system has been proven. As a preparation, it is therefore used in the field of food supplements as a substance that stimulates the metabolism and increases performance.
  • Synephrine can increase its effect in combination with other substances. For this reason, preparations with synephrine often also contain caffeine to mutually reinforce their effect.
  • Synephrine is available in various forms. The natural plant substance can be taken in the form of tablets, capsules or powder. The most common form of powder is the so-called "booster", which is taken dissolved in water before exercise to boost performance.

Synephrine: Our Selection

Buying and evaluation criteria for Synephrine

When buying Synephrine you should pay attention to some aspects, such as:

Based on these criteria, you can be sure that you are not making a wrong purchase. You make sure that the preparations meet your needs and give your body what it needs. To ensure safe use and consumption, you should always look for high quality and standardised tests. You can find this out from the test seals or certificates directly from the manufacturer.

Dosage

The proportion of synephrine in the preparations varies depending on the dosage form and manufacturer. Pay particular attention to the recommended dosage in the package insert or ask the product manufacturer. The correct dosage determines whether the active ingredient can develop freely.

Factors such as gender and body weight can determine the recommended dose for you.

In addition, the products usually contain other ingredients besides synephrine, which in combination reinforce each other's effect. This also influences the dosage.

Dosage form

The dosage form determines how quickly and easily you can take the preparations. Depending on which form of administration you prefer, there is a suitable dosage form.

In the case of powder preparations, you have to dissolve them in water to be able to take them. Capsules, on the other hand, can be swallowed without water if you don't have any.

All preparations are easier to take with water.

However, you should also take them with a little water to help them pass through the oesophagus and into the stomach.

The form is also a factor that can significantly determine the price. Products in capsule form are usually more expensive to produce than powder or tablets. So if you want to save some money, you can go for powder.

Package size

The dosage form can usually determine the package size. Preparations in capsule form are usually available in bulk. Depending on the product and manufacturer, you can save a little money. However, capsules are somewhat more expensive than tablets and powders. Therefore, you should compare the products with each other.

Especially because tablets come in individually shrink-wrapped packaging and therefore take up a lot of volume.

So you might pay more money than for capsule products.

Also, make sure you choose the right size pack for you, as the products usually only have a shelf life of a few years. So if you don't want to try new products on a regular basis, we recommend small pack sizes.

In order not to shorten the shelf life, you should store the dosage forms protected from light and in the original packaging.

Composition of the ingredients

Products with synephrine often contain other ingredients as well, since the active ingredients reinforce each other and the effect can unfold mutually.

Most products with synephrine are offered in combination with caffeine. The names differ depending on the product and the manufacturer. Coffee, green tea extract or guarana usually mean caffeine. Together with snyphrine, their effects are mutually enhanced, so manufacturers use this property and put these ingredients together.

A large number of ingredients may indicate that these are highly processed products. Especially if they are stabilisers and chemically compounded.

Make sure the ingredient list is manageable and has natural substances. Then you can be sure that the products contain only the essential substances you need.

You should spend a little more for the quality of the products, as pure and high-quality ingredients have their price. So you should not save money on quality.

Guide: Frequently asked questions about synephrine answered in detail

In the following section we show you detailed information about synephrine. You will learn about the effects of synephrine and the current state of science. We have answered these and other important questions for you below.

What is synephrine and how does it work?

Synephrine is a plant substance that is found in the peel and flesh of bitter oranges. It is mainly found in bitter oranges, also called Citrus Aurantium, but is also found in other citrus fruits such as mandarins, lemons and clementines. Therefore, synephrine can be taken in naturally through our food.

Synephrin-1

Synephrine has a reputation as a fat burner. In nature, the substance occurs in a natural form in some citrus fruits.
(Image source: unsplash.com / Kelly Sikkema)

In the preparations, synephrine is usually declared as bitter orange extract (Citrus Aurantium).

On a chemical basis, it is a protoalkaoid, which the body can also produce itself. It is found in higher concentrations in bitter oranges (3). And since these are rarely offered and consumed, synephrine is offered by many manufacturers as a food supplement.

Synephrine has various properties and is therefore also used in various remedies. The most common remedies include:

  • Pre-workout boosters
  • Fat-burner
  • Appetite suppressant

In Asian medicine, synephrine has another use as bitter orange. There it is used together with herbs and spices and is said to help with digestive problems.

Effect as a performance-enhancing agent

Synephrine has an effect on the cardiovascular system. It has a stimulating effect and increases the body's blood pressure (1, 3). This is particularly popular with athletes, as they feel a marked increase in performance when taking synephrine and are better able to pursue their sporting activities.

With the help of caffeine, the effect of synephrine is enhanced (5, 8, 9). Not only do people feel more concentrated, but they also perform better. Synephrine preparations are mainly used in bodybuilding sports. Its performance-enhancing effect is appreciated there.

Effect as a fat burner

The plant ingredient has a reputation as a fat burner. This is confirmed in a study in the British Journal of Clinical Pharmacology (1). However, the fat-burning effect only occurs in conjunction with physical exertion. If the user does not exercise, there is no noticeable effect.

In this study, healthy adults were administered synephrine before an exercise test. A change in fat and carbohydrate burning was observed with mild exertion. Fat burning was significantly increased by taking synephrine (10).

The study concludes that athletes burn 7 grams more fat by taking synephrine before exercise. However, it also comes to the conclusion that the exact mode of action of synephrine for fat burning is not exactly clear (1, 6). This still needs to be investigated in further studies.

Effect as an appetite suppressant

Appetite suppressants that contain synephrine advertise that they inhibit appetite. The effects of synephrine, such as the increase in blood pressure and the stimulation of the metabolism, can promote this effect (7).

Studies show that synephrine preparations can influence appetite by accelerating the pulse and increasing blood pressure (6, 7). Whether synephrine can actually help you lose weight directly has not yet been proven.

Where does synephrine occur?

The plant substance occurs as a metabolic product in some plants. These include bitter orange and many other citrus fruits. For this reason it is also found in the processed products of citrus fruits. However, it is present there in very low concentrations.

Synephrine is found in both the peel and the pulp of citrus fruits. In the production of food supplements, however, it is mainly the peel of the fruit that is used, as this is where the synephrine is found in higher concentrations.

When and for whom is it useful to take synephrine?

Synephrine can be taken by anyone who suffers from poor performance and wants to burn fat because of its assumed effect. However, synephrine preparations are predominantly aimed at adults who are physically active so that the synephrine effect can unfold freely.

Since synephrine can also be obtained through a balanced diet, its intake can be considered safe. Here, too, it is the same as with other ingredients. They should only be consumed in moderation,

Synephrin-2

In capsules, synephrine can be taken in high doses. Therefore, pay attention to the synephrine content in these products so that you do not exceed the recommended amount.
(Image source: unsplash.com / Avinash Kumar)

The areas of application in which synephrine is used include:

  • Overweight
  • Poor performance
  • Lack of concentration
  • Cravings

There is no clear evidence on a scientific basis that synephrine alleviates these areas of application. However, in some studies this is the case, but the processes behind this cannot be explained exactly. Therefore, further studies and research on a long-term basis are needed.

What types of synephrine are there?

The plant ingredient synephrine is usually processed before it can be ingested. Since it is found in the fruits of the bitter orange, they are industrially processed so that the synephrine can be consumed in a concentrated and isolated form. We distinguish between two different types in this section:

The liquid variant contains several ways in which synephrine can be taken, for example in the form of tea or as drops. We will explain the advantages and disadvantages of both variants in more detail in the next few paragraphs.

Type Description
Synephrine as a powder it consists of fine, solid and dry particles of the substance and may contain one or more active ingredients and secondary substances. The powder is often used in the field of pharmacy for the production of other medicinal forms.
Synephrine as capsules, tablets They belong to the most common solid dosage form of preparations. The active ingredient can be easily dosed in this form and is also easy to transport. The capsule shell protects the active substance from external influences such as light and oxygen. This makes them durable.

Synephrine powder

In the field of performance enhancement, synephrine is mainly available as a powder. There are numerous additives for a wide range of flavours that make it easier to take synephrine and adjuvants.

Synephrin-3

The powder form often serves as a starting material for other preparations for admixture. Therefore, synephrine powder is also used as a starting material for synephrine capsules and tablets.
(Image source: unsplash.com / David Gabrielyan)

The advantage of powder is that it is easy to dose. You can vary and adjust your consumption according to your needs. However, you need liquid to take the preparation. We recommend water for taking the ingredient so that the substances do not react with the liquid.

Advantages
  • Easy to take
  • Individual dosage
  • Various additives for a pleasant taste
Disadvantages
  • Can only be taken with liquid
  • Lower shelf life

Synephrine tablets, capsules

This type of solid preparation is very suitable for taking your synephrine requirements on the go. The individual tablets and capsules contain the synephrine in a well-dosed form. This saves you the hassle of dosing and can save you valuable time.

Often, these forms also have helpful accompanying substances, such as caffeine, so that the effect of the synephrine is intensified. This allows it to unfold its full effect.

Advantages
  • Cover or coating protects ingredient
  • Available in bulk
  • Easy to transport
Disadvantages
  • Usually more expensive
  • May remain in mouth when swallowed

Some tablets are coated with a thin layer that protects them from influences and makes them last longer. In capsules, the capsule shell does this. These protective layers are usually tasteless and can make it easier for some users to take.

If you find it difficult to swallow these solid preparations, there are also special products that can be softened with water beforehand, making them easier to swallow.

How is synephrine taken and how should it be dosed?

Synephrine is taken by mouth for almost all preparations. The recommended dosage in the manufacturer's package insert should be observed.

The German Federal Institute for Risk Assessment (Bundesinstitut für Risikobewertung) has classified excessive doses of synephrine as unsafe, as this could increase the likelihood of side effects.

Generally, no more than 6.7 mg of synephrine per day should be taken in supplements (2).

However, many products with synephrine contain significantly higher dosages and are therefore classified as questionable by the authorities. Especially the products of manufacturers from other EU countries do not go through EU standards and often do not declare the dosage of synephrine on their products.

Therefore, you should definitely look for certified preparations with a recommended dosage to avoid too high a dosage of synephrine and thus the risk of side effects.

What are the possible side effects of taking synephrine?

Synephrine affects the body's cardiovascular system. Just like caffeine does. Therefore, these substances are often used in combination to enhance their effects. This can also cause side effects, such as increased blood pressure or palpitations. An overdose of synephrine in combination with caffeine can even lead to a heart attack. This is confirmed by the results of some clinical studies (4).

In several reports, adverse effects such as cardiac arrhythmias were shown in healthy volunteers after taking synephrine with caffeine. Increased intake of synephrine, especially in combination with caffeine and exercise, may therefore be associated with cardiovascular risks (4).

Make sure that you take tested and certified synephrine preparations from Germany. This way you can be sure that there are no illegal additives that could cause additional side effects or even be harmful to your health.

When taking synephrine supplements, always follow the recommended dose as stated in the instructions for use. If you are not sure, you can get advice at the pharmacy or consult a doctor.

What are the alternatives to synephrine?

There are other substances that have a similar effect to synephrine. These include burning fat, increasing performance and curbing appetite. We have summarised the substances and their scientific basis in the following table:

Alternative Explanation
L-carnitine The best-known alternative to synephrine is L-carnitine. Preparations with this ingredient are already available in many supermarkets. Taking it is said to lead to increased fat burning. For this reason, L-carnitine is often described as a so-called fat burner. However, its mode of action could not be clearly confirmed in studies (11).
Ephedrine This alternative is chemically and pharmacologically related to synephrine. In Germany, unlike synephrine, the active ingredient requires a prescription. Ephedrine is supposed to perk you up, curb your appetite and raise your blood pressure. However, this has not been clearly proven in studies (12).

Photo source: Guillem/ 123rf.com

References (12)

1. Gutiérrez-Hellín J, Del Coso J. Acute p-synephrine ingestion increases fat oxidation rate during exercise. Br J Clin Pharmacol. 2016 Aug;82(2):362-8. doi: 10.1111/bcp.12952. Epub 2016 May 7. PMID: 27038225; PMCID: PMC4972152.
Source

2. Stellungnahme Nr. 004/2013 des BfR vom 16. November 2012
Source

3. Lebensmittelsicherheit, Nahrungsergänzungsmittel im Sport, BfR2GO, 172018, S.22-25
Source

4. Bakhyia, N., Dusemund, B., Richter, K. et al. Gesundheitliche Risiken von Synephrin in Nahrungsergänzungsmitteln. Bundesgesundheitsbl 60, 323–331 (2017). https://doi.org/10.1007/s00103-016-2506-5
Source

5. Scientific Opinion on the safety of caffeine, Safety of caffeine; EFSA Journal 2015;13(5):4102
Source

6. Stohs SJ. Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and p-Synephrine. Phytother Res. 2017 Oct;31(10):1463-1474. doi: 10.1002/ptr.5879. Epub 2017 Jul 28. PMID: 28752649; PMCID: PMC5655712.
Source

7. Jung YP, Earnest CP, Koozehchian M, Galvan E, Dalton R, Walker D, Rasmussen C, Murano PS, Greenwood M, Kreider RB. Effects of acute ingestion of a pre-workout dietary supplement with and without p-synephrine on resting energy expenditure, cognitive function and exercise performance. J Int Soc Sports Nutr. 2017 Jan 12;14:3. doi: 10.1186/s12970-016-0159-2. PMID: 28096758; PMCID: PMC5234109.
Source

8. Gutiérrez-Hellín J, Del Coso J. Effects of p-Synephrine and Caffeine Ingestion on Substrate Oxidation during Exercise. Med Sci Sports Exerc. 2018 Sep;50(9):1899-1906. doi: 10.1249/MSS.0000000000001653. PMID: 29727404.
Source

9. Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807. doi: 10.2165/00007256-200131110-00002. PMID: 11583104.
Source

10. Gutiérrez-Hellín J, Del Coso J. Dose-Response Effects of p-Synephrine on Fat Oxidation Rate During Exercise of Increasing Intensity. Phytother Res. 2018 Feb;32(2):370-374. doi: 10.1002/ptr.5937. Epub 2017 Oct 11. PMID: 29024325.
Source

11. Dr. Nina Enthaler, Rechercheservice Evidenzbasierte Medizin, PMU Salzburg, „Fat-burner“ L-Carnitin?, Deutscher Ärzte-Verlag | ZFA | Z Allg Med | 2012; 88 (9)
Source

12. Istituto Auxologico Italiano, Wirkung auf den Energiestoffwechsel auf zellulärer Ebene der Diät plus Behandlung mit Ephedrin und Koffein bei Fettleibigkeit, ClinicalTrials.gov, Nov 2007
Source

Why you can trust me?

Wissenschaftliche Studie
Gutiérrez-Hellín J, Del Coso J. Acute p-synephrine ingestion increases fat oxidation rate during exercise. Br J Clin Pharmacol. 2016 Aug;82(2):362-8. doi: 10.1111/bcp.12952. Epub 2016 May 7. PMID: 27038225; PMCID: PMC4972152.
Go to source
Bundesinstitut für Risikobewertung
Stellungnahme Nr. 004/2013 des BfR vom 16. November 2012
Go to source
Bundesinstitut für Risikobewertung
Lebensmittelsicherheit, Nahrungsergänzungsmittel im Sport, BfR2GO, 172018, S.22-25
Go to source
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz
Bakhyia, N., Dusemund, B., Richter, K. et al. Gesundheitliche Risiken von Synephrin in Nahrungsergänzungsmitteln. Bundesgesundheitsbl 60, 323–331 (2017). https://doi.org/10.1007/s00103-016-2506-5
Go to source
Europäische Behörde für Lebensmittelsicherheit - EFSA
Scientific Opinion on the safety of caffeine, Safety of caffeine; EFSA Journal 2015;13(5):4102
Go to source
Wissenschaftlicher Aufsatz
Stohs SJ. Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and p-Synephrine. Phytother Res. 2017 Oct;31(10):1463-1474. doi: 10.1002/ptr.5879. Epub 2017 Jul 28. PMID: 28752649; PMCID: PMC5655712.
Go to source
Wissenschaftliche Studie
Jung YP, Earnest CP, Koozehchian M, Galvan E, Dalton R, Walker D, Rasmussen C, Murano PS, Greenwood M, Kreider RB. Effects of acute ingestion of a pre-workout dietary supplement with and without p-synephrine on resting energy expenditure, cognitive function and exercise performance. J Int Soc Sports Nutr. 2017 Jan 12;14:3. doi: 10.1186/s12970-016-0159-2. PMID: 28096758; PMCID: PMC5234109.
Go to source
Wissenschaftliche Studie
Gutiérrez-Hellín J, Del Coso J. Effects of p-Synephrine and Caffeine Ingestion on Substrate Oxidation during Exercise. Med Sci Sports Exerc. 2018 Sep;50(9):1899-1906. doi: 10.1249/MSS.0000000000001653. PMID: 29727404.
Go to source
Wissenschaftlicher Aufsatz
Graham TE. Caffeine and exercise: metabolism, endurance and performance. Sports Med. 2001;31(11):785-807. doi: 10.2165/00007256-200131110-00002. PMID: 11583104.
Go to source
Wissenschaftliche Studie
Gutiérrez-Hellín J, Del Coso J. Dose-Response Effects of p-Synephrine on Fat Oxidation Rate During Exercise of Increasing Intensity. Phytother Res. 2018 Feb;32(2):370-374. doi: 10.1002/ptr.5937. Epub 2017 Oct 11. PMID: 29024325.
Go to source
Wissenschaftlicher Aufsatz
Dr. Nina Enthaler, Rechercheservice Evidenzbasierte Medizin, PMU Salzburg, „Fat-burner“ L-Carnitin?, Deutscher Ärzte-Verlag | ZFA | Z Allg Med | 2012; 88 (9)
Go to source
Wissenschaftliche Studie
Istituto Auxologico Italiano, Wirkung auf den Energiestoffwechsel auf zellulärer Ebene der Diät plus Behandlung mit Ephedrin und Koffein bei Fettleibigkeit, ClinicalTrials.gov, Nov 2007
Go to source
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