Phenylethylamine: A Monoamine That Promises Much But Doesn’t Deliver!

Since the last few decades, a plethora of prescription drugs for treating obesity have been tried.

Some like sibutramine have enjoyed immense popularity, only to be withdrawn later on due to serious adverse effects associated with their use (Doslikova et al., 2013; Cello & Rogers, 2013; Goldenberg, 2012).

Monoamine reuptake inhibitors are a class of drugs – because of their ability to induce stimulation of the adrenergic system – that have emerged as a new method of therapy to cause weight loss. Not surprisingly then, appetite suppression and increased resting metabolic rate are some of the mechanisms that have attributed to them. Some of these drugs are phenylethylamine, fluoxetine, sertraline, sibutramine, fluvoxamine, desipramine, imipramine and topiramate (Walsh et al., 1997; Lam, Garfield, Marston, Shaw, & Heisler, 2010).

Phenylethylamine, also known as ‘a love drug’ owing to its presence in chocolates (and red wine) and because it has been shown to increase ‘mounting behaviour’ in animal studies (Segal, Shohami, & Jacobowitz, 1984), is of particular interest since it was one of the first of these ‘trace’ monoamines to be discovered in the human body. Traditionally, phenylethylamine has been suggested for use in schizophrenia and affective disorders (Nakagawara, 1986). However, it may also have weight-reducing abilities.

Let us have a closer look at how effective it is and whether it is worth using it.

What is Phenylethylamine?

Phenylethylamine (PEA) is an amine produced endogenously in the human (and other mammalian) brain (Nakagawara, 1986). Chemically, it resembles amphetamines.

Research suggests that PEA may reduce body weight (Popplewell, Coffey, Montgomery, & Burton, 1986; Nakagawara, 1986).

Furthermore, PEA may be helpful in improving exercise performance as well – it has been shown to promote energy levels, elevate mood, mental focus and aggression (Sabelli & Javaid, 1995). L-phenylalanine, the amino acid precursor of PEA also elevates mood (Sabelli & Javaid, 1995).

Methods by Which Phenylethylamine Causing Fat Loss

PEA is a trace amine, i.e. it is produced in the human body in minute amounts – as compared to other monoamines like noradrenaline (NA) or dopamine (DA) (Nakagawara, 1986).

Phenylethylamine causes increased levels of NA and DA due to inhibition of monoamine oxidase (MAO). Subsequent stimulation of the adrenergic system then becomes responsible for most of the phenylethylamine actions (Parker & Cubeddu, 1988; Mesfioui et al., 1998). Additionally, PEA may also have a direct action mimicking NA and DA (Knoll, Miklya, Knoll, Marko, & Racz, 1996; Boulton, Juorio, & Paterson, 1990).

Some of the methods by which PEA supposedly causes weight loss (Nakagawara, 1986; Popplewell et al., 1986) are:

• Suppression of appetite and decreased food intake
• Increase in motor activity and hence metabolic rate
• Inhibition of fat absorption in the gut (Curtis-Prior, Oblin, & Tan, 1980)

How to Use Phenylethylamine for Fat Loss?

Fat loss supplements containing phenylethylamine will typically contain doses ranging from 500 to 750mg per capsule. These are to be taken as 1-2 capsules in a day – evenly spaced and with meals.

A word of caution here: phenylethylamine use is contraindicated in the following conditions:

• High blood pressure
• Heart conditions
• When using other stimulants (like caffeine)
• When using monoamine oxidase inhibitors

Long-term safety of phenylethylamine has not been studied and as such, it should not be used for long-term treatment of obesity. Also, it is strictly contraindicated in those under the age of 18 years.

Other Benefits of Phenylethylamine Use

PEA may have some possess therapeutic value in patients of depression being treated with a selective monoamine oxidase B inhibitor (Sabelli & Javaid, 1995).

In addition to anti-obesity actions, PEA (not unlike fenfluramine or amphetamines) has been shown to acutely reduce plasma triglyceride levels. But this is clinically too insignificant to be of benefit in preventing cardiovascular diseases (Curtis-Prior et al., 1980).

Reported Adverse Effects of Phenylethylamine

Use of phenylethylamine may be associated with mild general symptoms (Luthy & Schlatter, 1983; Lapin, 1993) like:

• Headache
• Anxiety
• Dizziness
• Discomfort

Adverse effects of PEA related to the cardiovascular system are more likely due to the release of endogenous norepinephrine from adrenergic nerve endings (Liang & Sprecher, 1979); these may be:

• Tachycardia (increase in heart rate)
• Hypertension (raised blood pressure)

Scientific Evidence for Phenylethylamine

Studies outlining the effectiveness of PEA in causing loss of body weight are far and few (Nakagawara, 1986; Popplewell et al., 1986).

Furthermore, opinion is divided regarding the adverse effects that PEA causes. Over the past few decades, dietary restriction has been recommended for those suffering from migraine. This is in view of the presence of biogenic amines (including PEA) in some foods – especially in chocolates and red wines.

• For instance, some studies report that PEA may induce headaches (Luthy & Schlatter, 1983) and worsen migraine while others deny any such link (Jansen, van, Bottema, & Dubois, 2003)
• Whereas in those suffering from diseases as depression and motor function, long-term use of PEA may pose a grave risk, no such increase in risk is seen in the normal population (Sengupta & Mohanakumar, 2010; Jansen et al., 2003)

Thus, it can be concluded that the effectiveness of PEA in causing weight loss has not been proven conclusively. Also, the safety of PEA either for short-term or long-term treatment of obesity has not been established.

Our Verdict on Phenylethylamine

There is ample evidence to suggest that phenylethylamine may elevate mood. However, studies outlining its effectiveness regarding the loss of body weight are far and few. Also, it has a distinct adverse effects profile.

In such circumstances, it is our recommendation that it is better to avoid phenylethylamine for causing loss of body weight.