A South American plant that produces berries with a high concentration (up to 7.5%) of caffeine.  Guarana extracts have been used in traditional folk medicine, as well as a base for soft drinks.  In North America, standardized guarana extracts are used as a “natural” source of caffeine in weight loss supplements and energy drinks.

See Paul’s review, “Guarana – Caffeine’s Fat-Burning Connection” for more information.

A naturally-occurring metabolite of glucose. Glucuronolactone is used in energy drinks as well as some pre-workout supplements as an energy booster. It’s also sold in bulk powder form. There are no studies on glucuronolactone that validate its use for enhancing mood or energy, however – the evidence is strictly anecdotal.

GABA stands for gamma-aminobutyric acid, an inhibitory neurotransmitter derived from glutamate (an amino acid and excitatory neurotransmitter).  When taken in supplemental form, GABA has a mild sedative effect that can aid relaxation and sleep.  Supplemental GABA may also stimulate resting growth hormone production.

A B-vitamin needed for proper nucleic acid and amino acid metabolism.  Folic acid plays a particularly critical role in the metabolism of the amino acid methionine; deficiency can result in a buildup of homocysteine – a harmful metabolite that’s a marker of cardiovascular disease risk.  Adequate folic acid intake is particularly important during pregnancy, for the prevention of neural tube defects.

See: “Folic Acid Information & Benefits” and the Linus Pauling Institute Micronutrient Information Center for more information.

One of the principle, bioactive alkaloids of Evodia rutaecarpa.  Like capsaicin, evodiamine is a vanilloid receptor agonist, with thermogenic and (potential) anti-obesity effects.  Evodiamine may also have therapeutic potential, due to its anti-tumor and analgesic effects.

Evodiamine is often added to fat burners (purified or as a standardized extract of Evodia) to promote thermogenesis.  It’s alleged to invoke a “shivering” response, although this is strictly anecdotal.

The fruits of Evodia rutaecarpa are known as “Wu Zhu Yu” (or “Wu Chu Yu”) in traditional Chinese medicine. Evodia fruits contain several bioactive alkaloids with therapeutic potential, including evodiamine and rutaecarpine.  Experimentally, Evodia extracts have been shown to have anti-inflammatory, anti-allergenic and gastroprotective effects.

Evodia extracts, often standardized for evodiamine, are frequently added to fat burners to enhance thermogenic effects.

An arginine salt and alternative to AAKG used in some nitric oxide (NO)-boosting supplements.

Also known as beta-cryptoxanthin.  A carotenoid pigment with pro-Vitamin A activity.  The Vitamin A activity of beta-cryptoxanthin is 1/24th that of pre-formed Vitamin A (retinol).  Red-orange vegetables and fruits such as pumpkins, papayas, sweet red peppers and orange juice are rich food sources of this compound.

See Creatine Ethyl Ester.

Also known as CEE.  Creatine ethyl ester is alleged to be more stable, soluble and bioavailable than creatine monohydrate.  Nonetheless, tests by Dr. Mark Tallon demonstrated that—contrary to claims—CEE is actually less stable than creatine monohydrate during digestion.  

Currently, there is no evidence that CEE actually works better than creatine monohydrate w/respect to gains in lean mass or strength.