Agriculture Reference
In-Depth Information
tAble 13.1 (continued)
bioactive components in foods, sources, and Purported benefits
bioactive component
sources
benefits
Flavonols: quercetin,
kaempferol
Apples, broccoli, tea, onions,
blueberries, red wine
Scavenge free radicals,
antioxidant, anti-inflammatory
Pronathocyanidins
Cranberry, apple, strawberry,
wine, cinnamon
Heart health, antioxidants,
urinary tract health
Flavones: luteolin, apigenin
Celery, parsley, sweet peppers
Antioxidants, anticancer
Isoflavones: genestein, diadzein,
glycitein
Soy and other beans
Menopausal health, bone health
Resveratrol
Wine, grapes, peanuts
Anticancer, longevity
Curcumin
Tumeric
Anti-inflammatory, anticancer
CHD, coronary heart disease; LDL, low-density lipoprotein.
in a wide range of bars. Soy delivers a range of health benefits, as reviewed by
Messina et al. (2001), Hendrich and Murphy (2001), and Friedman and Brandon
(2001). Raw soy protein contains several antinutritional components, including
Bowman-Birk inhibitor, Kunitz inhibitor, and lectins. The lectins are more labile
to heat, and the protease inhibitors are significantly reduced either by processing
or refining of the protein.
The Bowman-Birk inhibitor is thought to be responsible for soy's protection against
obesity, diabetes, and anticarcinogenic activity (Friedman and Brandon, 2001).
Isoflavones are major components found in soy foods that provide benefits in
menopausal health and in bone health. The isoflavones in soy are present as agly-
cones, glucosides, malonylglucosides, and acetylglucosides. Hendrich and Murphy
(2001) provided extensive data on the distribution of the isoflavones in soy. Table 13.2
summarizes the isoflavone contents in a variety of soy-based products.
The hypocholesterolemic influence of soy foods was first reported by Meeker
and Kesten (1940). The mechanism has yet to be clearly defined. Carroll and
Kurowska (1995) suggested that it was related to the amino acids and peptide struc-
ture, Setchell (1985) proposed isoflavones were factors, and Potter et al. (1993) sug-
gested that the combination of saponins and soy protein may have been responsible.
It is highly likely that the effects are a result of all of the components, not a single
factor. Zhan and Ho (2005) did a meta-analysis that measured the benefits of soy
on serum lipid profiles. The health benefits of soy are supported by several epide-
miological studies showing benefits in reduced risk of breast, prostrate, and colon
cancer (Messina et al., 1997; Hendrich and Murphy, 2001), improved bone health,
and protection against cardiovascular disease (Hendrich and Murphy, 2001; McCue
and Shetty, 2004).
The current status of the influence of soy isoflavones on breast cancer risk have
recently been reviewed by Duffy et al. (2007), describing current proposed mecha-
nisms for protection against breast cancer.
Search WWH ::




Custom Search