Biology Reference
In-Depth Information
8. SPICES
Other than macronutrients, there are other phytochemicals that are
known to lower glycemic response by various mechanisms. Spices are
one such food group that have been shown to have hypoglycemic and hyp-
oinsulinemic effects. Cinnamon has been used for many studies in both
nondiabetic and diabetic subjects. An active ingredient of cinnamon called
methyl hydroxychalcone polymer (MHCP) has been proven to mimic insu-
lin and promote glucose disposal into the skeletal muscle (
Jarvill-Taylor,
Anderson, & Graves, 2001
). This mechanism is due to upregulation of insu-
lin signaling cascade by phosphorylation of the insulin receptor substrate as
shown in animal studies
(
Qin et al., 2003
).
Khan, Safdar, Ali Khan, Khattak,
and Anderson (2003)
was the first to report the beneficial effect of cinnamon
on glycemic profile of diabetic subjects. However, a study in postmeno-
pausal overweight type 2 diabetic women did not give an effect of cinnamon
consumption for 6 weeks at a dose of 1.5 g/day. This may be due to the
effect of some subject characteristics on the mechanism by which cinnamon
influences insulin levels (
Vanschoonbeek, Thomassen, Senden, Wodzig, &
The use of herbal teas has shown a significant effect on reducing the GI of
white bread (
Faqih & Al-Nawaiseh, 2006
). Four types of herbal teas such as
cinnamon tea, fenugreek seed tea, black tea, and anise tea were compared in
two doses per cup in healthy subjects. The cinnamon tea at 4 and 8 g/cup
reduced the GI of white bread by 50% with no dose-dependent effect. The
effect of cinnamon was attributed to the presence of the polyphenol com-
poundMHCP in cinnamon. The fenugreek tea was the one that reduced the
GI considerably with a high dose of 10 g/cup. The lower dose of 6 g/cup
resulted in a 40% reduction in GI and the higher 10 g/cup dose resulted in a
60% reduction in GI of white bread. In fenugreek, the hypoglycemic effect
is often due to the presence of galactomannan fiber and also a specific amino
acid called 4-hydroxy isoleucine that has insulin-stimulating action. The
black tea was used at lower doses of 1.5 g and 2.5 g/cup and both reduced
the GI of white bread but the GI was still in the high GI range. Again this
effect is also attributed to the polyphenols in tea, specifically EGCG that has
hepatic glucose-inhibition effect and insulin-stimulating effect. The aniseed
tea was tried in 6 and 10 g doses and both retained the GI at high category for
the white bread.
