Table 4.
Adverse effects of consuming MCT oil as an ergogenic aid
| Study | Dose of MCT | Placebo(s) | Consumption | Adverse reactions (n) |
|---|---|---|---|---|
| Angus et al. (2000)9 | 6% CHO solution w/4.2% MCT solution | 6% CHO solution; sweet placebo | 250 mL/15 minutes for ~2 hours | GI discomfort (4); severe symptoms such as vomiting and diarrhea (2/4) |
| Décombaz et al. (1983)24 | 25 g MCT+2.5 g caseinate | 50 g CHO+2.5 g caseinate | 1 hour prior to ex | None reported |
| Goedecke et al. (1999)23 | 10% CHO+1.72% MCT; 10% CHO+3.44% MCT solution | 10% CHO solution | Ingested 400 mL prior to ex and then 100 mL every 10 minutes | Vomited with the low MCT dose (1); experienced diarrhea; excessive bloating, cramps, and nausea were reported during the high MCT dose (1) |
| Goedecke et al. (2005)25 | 32 g MCT+(4.3% MCT+10% CHO solution) | 75 g CHO+200 mL of 10% CHO | Ingested prior to ex and every 20 minutes during ex | Experienced GI distress with MCT supplement (4); common reports of nausea, vomiting, stomach cramps, bloating, and diarrhea |
| Horowitz et al. (2000)26 | ~25 g MCT+0.72 g/kg sucrose | 0.72 g/kg sucrose | 1 hour prior to ex | Observed GI distress such as nausea and diarrhea (not reported) |
| Ivy et al. (1980)27 | 30 g MCT+skim milk | Nothing; 30 g LCT+skim milk; cereal+skim milk | 1 hour prior to ex | Diarrhea (3) |
| Jeukendrup et al. (1995)28 | 29 g MCT; equicaloric CHO-MCT suspension; 29 g MCT+CHO suspension | 15% CHO solution | 4 mL/kg prior to ex+2 mL/kg every 20 minutes during ex | None reported |
| Jeukendrup et al. (1996)10 | 28.5 g MCT+93.1 g CHO; LG vs. HG | 156.2 g CHO | 4 mL/kg prior to ex+2 mL/kg every 20 minutes during ex | None reported |
| Jeukendrup et al. (1996)11 | 29 g MCT+150 g CHO; 29 g MCT+214 g CHO | 150 g CHO solution; nothing | 4 mL/kg prior to ex and 2 mL/kg every 20 minutes | Some levels of GI discomfort in all trials including placebo: nausea, intestinal cramps, and belching |
| Jeukendrup et al. (1998)11 | 85 g MCT; 85 g MCT+170 g CHO | 170 g CHO; artificially flavored water | 8 mL/kg during the first minute of warm-up followed by 2 mL/kg every 15 minutes | Vomited (2) and experienced diarrhea (3) proceeding MCT trial; GI cramps occurred significantly more frequently with MCT |
| Massicotte et al. (1992)13 | 25 g MCT | Water; 57 g CHO | MCT taken 1 hour prior, H2O given in (8) equal portions during ex (125 mL); CHO taken in (8) portions during ex (125 mL H2O+7.1 g CHO) | None reported |
| Van Zyl et al. (1996)15 | 4.3% MCT emulsion; 4.3% MCT+10% CHO | 10% wt/vol CHO solution | 400 mL taken prior to ex; 100 mL of solution given every 10 minutes during ex | None reported |
| Vistisen et al. (2003)16 | 1.5 g/kg MLM+2.4 g/kg CHO | 2.4 g/kg CHO | 400 mL taken prior to ex; 200 mL every 15 minutes during ex | No difference in GI distress |
| Chronic use | ||||
| Misell et al. (2001)29 | 30 g MCT | 28 g LCT oil | Ingested (2) shakes per day for 2 weeks | All participants experienced GI distress that lessened as they continued use; Not assessed formally |
| Ööpik et al. (2001)30 | ~35 g MCT | ~35 g commercial cooking oil | Ingested in (2) equal portions per day for 2 weeks | Mild GI distress the first few days (2/6) |
MCT, medium-chain triglyceride; CHO, carbohydrate; GI, gastrointestinal; ex, exercise; LCT, long-chain triglyceride; LG, low glycogen; HG, moderate-high glycogen.