Pyruvate. Just the Facts
Pyruvate (also known as pyruvic acid) is a molecule formed from the sugar glucose (blood sugar) during the process known as glycolysis, which is one of the energy generating pathways that we use to make ATP (adenosine triphosphate), our ultimate energy molecule. Basically, when you make energy in glycolysis, you start
with the sugar glucose, run in through some metabolic steps, and end up with pyruvate. ATP (energy) is formed during the process.
Pyruvate also occurs naturally in food with fruits and vegetables containing the greatest amounts of pyruvate. Red apples for example have some of the highest concentrations of pyruvate with 500 mg per apple. The amount in food is much less than that contained in pyruvate supplements. Pyruvate and Weight Loss Of the few studies available which refer to pyruvate and weight loss, all of them indicate that it works. In one study, overweight women (defined as being over 200 lbs) who consumed a low calorie diet and pyruvate for 21 days lost 37% more weight and 48% more fat than overweight women eating only a low calorie diet (and not using pyruvate). This figure appears
very impressive but things look a little differently when you look at the actual number of pounds lost. In this study, the women using pyruvate lost an average of 12.98 pounds of body weight while the women not using the pyruvate lost an average of 9.46 pounds. That's an average difference of only 3.52 pounds. With respect to how much fat was lost, women using pyruvate lost an average of 8.8 pounds of fat while those not using pyruvate lost an average of 5.6 pounds. In other words, women who
supplemented with pyruvate lost about 3 pounds more than women not using it.
In another study, overweight women (again over 200 lbs) eating a low calorie diet plus pyruvate lost an average of 14.3 pounds while those only on the low calorie diet lost 12.3 pounds. This amounts to only about a 2 pound difference. As for fat loss, the women in this study who supplemented with pyruvate lost an average of 9.5 pounds. Those not using pyruvate lost an average of 7.7 pounds. This amounts
to only about 1.5 pounds difference.
You should also know that the weight and fat loss noted in these studies may not be 100% accurate because body fat loss was determined via bioelectrical impedance and not the gold standard of underwater weighing. Bioelectric impedance was most likely chosen because it is less intrusive than submerging someone in water. Pyruvate and the Inhibition of Regaining of Weight Now
let's talk about how pyruvate seems to inhibit the regaining of weight after it has been lost. From all the research that I have been able to find, this claim seems to be based on only one study. In this investigation overweight women (average weight 228 pounds) consumed a low calorie diet for three weeks and then went on a three day high calorie diet to purposely regain the lost weight. Some women used pyruvate during the dieting process. For those women who did not receive pyruvate,
an average of about 6.4 pounds of weight was regained. For women who received pyruvate, an average of about 4 pounds of body weight was regained. This amounts to about a 2.4 pounds difference. When we look at how much body fat was regained, we see a similar picture: women not using pyruvate regained an average of about 4 pounds of fat while those using the pyruvate regained an average of about 1.7 pounds of fat. Both of these figures, while relatively small are intriguing and are deserving of
further research. Pyruvate and the Suppression of Appetite One published peer-reviewed study has reported that pyruvate seemed to suppress appetite (in laboratory rats) when they were allowed to eat as much as they wanted. Little evidence seems to exist attesting to this effect in humans so it is unknown if these results can be extrapolated to people. This is unfortunate, for it represents a vast untapped area of pyruvate
research. Pyruvate and Metabolism Metabolism is the speed that we burn calories. Higher metabolisms mean in essence, that you use more calories in the same amount of time as someone with a slower metabolism. To date, the bottom line on pyruvate raising metabolism is this: earlier studies which studied pyruvate supplementation in rats did show increases in resting metabolism (the number of calories used at rest) but these
results seem to have never been confirmed in human studies. In fact, one human pyruvate study noted higher resting metabolisms in those not using pyruvate. Therefore, at the present time, there seems to be inconclusive evidence that pyruvate raises metabolism. Pyruvate and Cholesterol Levels With respect to pyruvate altering cholesterol levels, the evidence seems to indicate that pyruvate does not result in any significant
alterations in total cholesterol, HDL (good cholesterol), LDL (bad cholesterol) or triglycerides. Pyruvate Muscular Endurance One study has hinted that pyruvate increased the muscular endurance capacity of the triceps muscle by 20%. The subjects utilized in this study were 10 untrained men, so it is difficult to extrapolate how an athlete would respond to pyruvate supplementation based upon the results of non-athletes.
Another study found that the subject's ability to exercise to exhaustion on a stationary bicycle increased by 13 minutes. This is indeed interesting but because of the limited evidence it is difficult to extrapolate the effectiveness of pyruvate to athletes or strength trainers. Side Effects of Pyruvate Use Studies to date find pyruvate generally safe and well tolerated. Common complaints include occasional diarrhea, lose
or softened stools and intestinal gas. Pyruvate does not seem to affect heart rate, body temperature, or blood pressure. How Does Pyruvate Work? Currently, it is thought that supplemental pyruvate enhances muscular endurance by increasing the transport of glucose into the cells where it can be used for energy. How pyruvate supplementation augments weight and fat loss remains a mystery.
My Thoughts To date, most weight loss studies on pyruvate seem to have been done on either rats or obese women eating very low calorie diets. Little evidence exists on how pyruvate works in non-obese people eating a more normal diet.
Some of the pyruvate studies used sodium pyruvate. If you are considering using pyruvate and have high blood pressure you might want to switch to a sodium-free brand. About the author:
Joe Cannon, MS, CSCS, is an exercise physiologist, personal trainer, writer and health educator. He is the author of Nutritional Supplements: What Works and Why. A Comprehensive Review from A to Zinc and Nutrition Essentials, a Guidebook for the Fitness Professional. For more information visit his official website www.Joe-Cannon.com or drop Joe an email directly at JoeCannon@rcn.com
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