Starch Blockers: Scam or Hoax?
ISMD Award # 1R25GM086761-01
Xiaomin Jing and Keats Shwab
CONCLUSIONS
Should you take amylase inhibitors to lose weight?
INTRODUCTION
Starch Blockers and Weight Loss
Starch is a major source of calories in the average person’s diet.
Because starch is a large molecule, it must be broken down by
amylases before it can be absorbed by the body. Because of this,
Starch Blockers, which are meant to inhibit the activity of alphaamylases, are a popular dieting tool. However, there is doubt
concerning the effectiveness of such dieting aids.
Production of amylase inhibitors by bean plants
Beans and other high-starch plants are known to produce amylase
inhibitors. We investigated the reasons why production of such
compounds may be beneficial to these plants.
Not recommended.
Literature does not support claims of weight loss.
Vendors claim that newer tablets more effective than older
ones, but evidence for this not published.
Amylase inhibitors cause zinc and copper deficiencies in rats.
Why do bean plants produce amylase inhibitors?
Likely to prevent destruction by insect herbivory.
Alpha-amylase inhibitors do not act on the bean’s own amylases
but are effective at inhibiting those of insect species.
FUTURE DIRECTIONS
Perform testing of newer generation Starch Blockers, which the WholeHealth company
suggests are more effective than the inhibitors previously tested in published studies.･
Examine link between copper and zinc uptake and amylase inhibition. Why do starch
blockers lead to deficiencies in these elements?
REFERENCES
Starch Blockers and Weight Loss:
Commercial soybean starch blocker consumption: impact on weight gain and on copper, lead and zinc status of rats. J Umoren and C Kies Plant foods for human nutrition
(Dordrecht, Netherlands) 42 (2), 135-42 (Apr 1992)･
Starch blockers their effect on calorie absorption from a high-starch meal. Bo-Linn, G.W., et al., N Engl J Med, 1982. 307(23): p. 1413-6.
Partially purified white bean amylase inhibitor reduces starch digestion in vitro and inactivates intraduodenal amylase in humans. Layer, P., G.L. Carlson, and E.P. DiMagno,
Gastroenterology, 1985. 88(6): p. 1895-902.
Function of Bean Plant-Produced Amylase Inhibitors:
Structural basis for the inhibition of mammalian and insect alpha-amylases by plant protein inhibitors. Fran腔ise Payan Biochimica et biophysica acta 1696 (2), 171-80 (12
Feb 2004)
Advances in food research Emil Marcel Mrak, C. O. Chichester Academic Press, 1982
Alpha-amylase inhibitor from Phaseolus vulgaris (white kidney bean)