Calcium pyruvate, which is a carbohydrate found naturally in red apples, cheeses and red wine and is important for people on a reduced calorie diet to help the synthesis of amino acids. Scientists believe that Pyruvate may actually accelerate fat loss by increasing 'cellular respiration' in the body.
Pyruvate is the anionic form of the three-carbon organic acid, pyruvic acid. Pyruvate is a key intermediate in the glycolytic and pyruvate dehydrogenase pathways, which are involved in biological energy production. Pyruvate is widely found in living organisms. It is not an essential nutrient since it can be synthesized in the cells of the body. Pyruvate, however, is consumed in the diet. The average daily intake of this substance ranges between about 100 milligrams and 1 to 2 grams. Certain fruits and vegetables are rich in pyruvate. For example, an average-size red apple contains approximately 450 milligrams. Dark beer and red wine are also rich sources of pyruvate.
Pyruvate is also known as 2-oxopropanoate, alpha-ketopropionate, acetylformate and pyroracemate. Pyruvate and pyruvic acid are frequently use interchangeably, even though pyruvate is the anion of pyruvic acid and the form that occurs in living organisms.
Pyruvate may aid weight loss efforts. A clinical trial found that supplementation with 22–44 grams per day of pyruvate, when compared with placebo, enhanced weight loss and resulted in a greater reduction of body fat in overweight adults consuming a low-fat diet. Three controlled studies combining 6–10 grams per day of pyruvate with an exercise program, reported similar effects on weight loss and body fat. Animal studies suggest that pyruvate supplementation leads to weight loss by increasing the resting metabolic rate. A few clinical trials also indicated that pyruvate supplements may improve exercise endurance, though weight-lifting capacity did not improve.
Pyruvate serves as a biological fuel by being converted to acetyl coenzyme A, which enters the tricarboxylic acid or Krebs cycle where it is metabolized to produce ATP aerobically. Energy can also be obtained anaerobically from pyruvate via its conversion to lactate. At supraphysiological levels, pyruvate increases contractile function of hearts when metabolizing glucose or fatty acids. This inotropic effect is striking in hearts stunned by ischemia/reperfusion. The inotropic effect of pyruvate requires intracoronary infusion. Among possible mechanisms for this effect are increased generation of ATP and an increase in ATP phosphorylation potential. Another is activation of pyruvate dehydrogenase, promoting its own oxidation by inhibiting pyruvate dehydrogenase kinase. Pyruvate dehydrogenase is inactivated in ischemia myocardium. Yet another is reduction of cytosolic inorganic phosphate concentration. There are other possible mechanisms, such as enhanced sarcoplasmic reticular ion uptake, and release and reactive oxygen species scavenging.
Supraphysiological levels of pyruvate are reported to enhance aerobic endurance capacity. Again, the mechanism of this action is far from being well understood. Some studies indicate that pyruvate at supraphysiological levels increases the transport of glucose into muscle cells in a process known as blood glucose extraction. This could spare skeletal muscle glycogen stores.
The mechanism by which supraphysiological levels of pyruvate may lead to fat loss is unclear. Rats that consumed a diet supplemented with pyruvate and dihydroxyacetone reportedly had a lower respiratory quotient (RQ), indicating an increased utilization of fat as an energy source, as well as elevated resting metabolic rate. In addition, the rats that received pyruvate and dihydroxyacetone had elevated levels of thyroxine, lower levels of plasma insulin and lower rates of lipid synthesis in adipose tissue. Fat oxidation may be enhanced in some obese individuals administered pyruvate.