Glycerol

=Glycerol=

Definition:
Glycerol is a hyperhydrating agent that increases blood osmolality and, when accompanied by copious amounts of water, provides an osmotic drive that augments retention of large quantities of water otherwise eliminated by the kidneys (Wingo et al. 2004, p 170).

Sources:
Glycerol is found in fats. Fat molecules are made of one Glycerol molecule and three fatty acids. Fats are typically found in high concentrations in meats and animal porducts. The healthiest type of fats are mono and polyunsaturated fats. These can be found in highest concentrations in fatty cold water fish, including tuna, salmon, herring, and sardines. These fats are also found in sunflower oil, and avacado (Traister, 2011).

Recommendation:
Glycerol is recommended for highly trained, heat acclimated, aerobic endurance athletes such as runners and cyclists. Although there is conflicting research on the effectiveness of glycerol on hyperhydration, it shows possible effectiveness on increasing hydration level, decreasing cardiovascular strain, and improving thermoregulation during exercise in the heat, which may lead to an increase in performance (Beis et al. 2011 p 19)

Usage:
Typical dosage for hyperhydration is 1-1.5g/kg BW. It is typically a liquid that can be dissolved in 1.4-2L of water and consumed 1-3 hours before exercise bout (Beis et al. 2011, p 4). Glycerol is also used for dry skin, by being rubbed on affected areas. It has been used in treating stroke by being injected intravenously, but it is very dangerous and should never be taken intravenously. Glycerol has been used to treat constipation by being taken as a 2-4g suppository as well (Web MD, 2012). One study found that combining glycerol with creatine monohydrate was effective in increasing total body weight, including intracellular water and extracellular water (Beis et al. 2011, p 12).

Warnings & Side Effects:
Glycerol taken orally seems to be very safe. Side effects can include headaches, dizziness, bloating, thirst, nausea, and diarrhea. Red blood cell damage can occur when injected intravenously. The effect of glycerol during pregnancy is unknown, but should be avoided (Web MD, 2012).
 * This Statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent and diseases.**

Effectivness: 3/5
Conflicting data and lack of research only suggests this supplement could be effective in hyperhydration.

Safety: 3/5
Side effects are not harmful to body, but may cause distress that limits athletic ability.

Cost: 5/5
very inexpensive. ~$3 for 200mL.

Ease of Use: 4/5
Simply mix glycerol solution with water and drink.

Overall Ranking: 15/20
Overall this supplement shows promise. There is not enough research to fully endorse this product effectivness, but some studies have shown positive results. It is a hard supplement to find for oral use, but can be found as a cough and sore throat serum.

Articles:
Beis Y.L., Polyviou T., Malkova D., & Pitsiladis P.Y. (2011). The effects of creatine and glycerol hyperhydration on running economy in well trained endurance runners. //Journal of the International Society of Sports Nutrition,// 8 (24). doi:10.1186/1550-2783-8-24.

Wagner. R.D. (1999). Hyperhydrating with glycerol: Implication for athletic performance. //Journal of the American Dietetic Association,// 99(2), 207-211. Retrieved from [|www.ncbi.nlm.nih.gov/pubmed/9972189].

Wingo E.J., Casa J.D., Berger M.E., Dellis O.W., Knight C.J., & McClung M.J. (2004). Influence of pre-exercise hydration beverage on performance and physiologic function during mountain-bike races in the heat. //Journal of Athletic Training,// 39(2), 169-175. Retrieved from [].

Additional Sources:
Traister, J. (2011, August 7). Food sources of glycerol. Retrieved January 11, 2012, from [].

WebMD (December 2011). Glycerol. Retrieved January 11, 2012, from [].