286
16.3 Biological Activities of Grains
As the grains are used worldwide and are staple foods of many countries therefore
their use has the potential of impacting health outcomes. Major portion of grains is
carbohydrates which are useful source of energy, it also contains other valuable
dietary components e.g. phytochemicals (Okarter and Liu 2010), therefore mixing
of these grains into foods either whole grain or in the form of other products gives
vital nutritional differences. If we compare nutritional profile of whole grains and
milled grains, major difference noticed in dietary fiber, minerals, vitamins and other
bioactive compounds e.g. polyphenol which are antioxidants (Jonnalagadda et al.
2011). Various varieties of whole grains contain different nutritional composition
and therefore contains different bioactive compounds and activities, so produced
various biological effects in body (Donkor et al. 2012). Number of bioactive compounds present in grains along with other components are characterized with different physiological responses (Björck et al. 2012; Fardet 2010). In past many
researchers had reviewed the functional characteristics of whole grains, but still
they are not clarified completely (Björck et al. 2012). From literature, it is concluded that dietary fiber (important part of whole grains) provides number of health
benefits, but data from research shows that all whole grains are not reliable source
of dietary fibers e.g. brown rice contain 4.6 g/100 g while dark rye flour contain
23.8 g/100 g (US Food and Drug Administration [USFDA] 2012).
Many explanations regarding mechanism of whole grains activity were discussed
e.g. structure of starch, solubility properties and viscosity produced by fiber, along
with size of particles (Jonnalagadda et al. 2011), structure of food and gelatinization
(Björck et al. 2012). Soluble fiber present in whole grains may help to reduce level
of cholesterol in blood by production of bile while production of cholesterol may
also be inhibited by shot chain fatty acids which produced after fermentation of
grain polysaccharide. Risk of diabetes could be reduced by many minerals (Mg, Se)
and antioxidant (Vitamin E) present in whole grains (Jonnalagadda et al. 2011).
Oxidative stress and inflammation may also be reduced by polyphenolic antioxidants (Mateo Anson et al. 2010).
Importantly, it was observed that superior health effects were exerted through
consumption of whole grains in comparison to milled grains in diet, this effect
proved through epidemiological studies (Masters et al. 2010). Basal metabolic rate,
LDL and total cholesterol improved by consuming whole grains (Newby et al.
2007). Numerous studies had been conducted related dietary intake of whole grains
which associated with reduced risk of various disease but recommended consumption of whole grains is not met in many contraries including Canada, USA and
Australia. In developed country like USA recommendation to consume whole
grains were 500% more than present consumption while just 20% increment
observed in consumption, which were not up-to the mar (Whole Grains
Council 2009).
Similar conditions also observed in Australia where less than 1/3rd of whole
grain were consumed, which are far less than recommendation (Go Grains Health
S. Hassan et al.
16.3 Biological Activities of Grains
As the grains are used worldwide and are staple foods of many countries therefore
their use has the potential of impacting health outcomes. Major portion of grains is
carbohydrates which are useful source of energy, it also contains other valuable
dietary components e.g. phytochemicals (Okarter and Liu 2010), therefore mixing
of these grains into foods either whole grain or in the form of other products gives
vital nutritional differences. If we compare nutritional profile of whole grains and
milled grains, major difference noticed in dietary fiber, minerals, vitamins and other
bioactive compounds e.g. polyphenol which are antioxidants (Jonnalagadda et al.
2011). Various varieties of whole grains contain different nutritional composition
and therefore contains different bioactive compounds and activities, so produced
various biological effects in body (Donkor et al. 2012). Number of bioactive compounds present in grains along with other components are characterized with different physiological responses (Björck et al. 2012; Fardet 2010). In past many
researchers had reviewed the functional characteristics of whole grains, but still
they are not clarified completely (Björck et al. 2012). From literature, it is concluded that dietary fiber (important part of whole grains) provides number of health
benefits, but data from research shows that all whole grains are not reliable source
of dietary fibers e.g. brown rice contain 4.6 g/100 g while dark rye flour contain
23.8 g/100 g (US Food and Drug Administration [USFDA] 2012).
Many explanations regarding mechanism of whole grains activity were discussed
e.g. structure of starch, solubility properties and viscosity produced by fiber, along
with size of particles (Jonnalagadda et al. 2011), structure of food and gelatinization
(Björck et al. 2012). Soluble fiber present in whole grains may help to reduce level
of cholesterol in blood by production of bile while production of cholesterol may
also be inhibited by shot chain fatty acids which produced after fermentation of
grain polysaccharide. Risk of diabetes could be reduced by many minerals (Mg, Se)
and antioxidant (Vitamin E) present in whole grains (Jonnalagadda et al. 2011).
Oxidative stress and inflammation may also be reduced by polyphenolic antioxidants (Mateo Anson et al. 2010).
Importantly, it was observed that superior health effects were exerted through
consumption of whole grains in comparison to milled grains in diet, this effect
proved through epidemiological studies (Masters et al. 2010). Basal metabolic rate,
LDL and total cholesterol improved by consuming whole grains (Newby et al.
2007). Numerous studies had been conducted related dietary intake of whole grains
which associated with reduced risk of various disease but recommended consumption of whole grains is not met in many contraries including Canada, USA and
Australia. In developed country like USA recommendation to consume whole
grains were 500% more than present consumption while just 20% increment
observed in consumption, which were not up-to the mar (Whole Grains
Council 2009).
Similar conditions also observed in Australia where less than 1/3rd of whole
grain were consumed, which are far less than recommendation (Go Grains Health
S. Hassan et al.