Soy Isoflavones May Help with Weight Control in Breast Cancer Survivors
July
12,
2004
A recent study in 56 postmenopausal women who were breast cancer
survivors tested the effects of Soy Isoflavones versus an inactive
placebo. The soy Isoflavones were supplemented at a dosage of 114mg
a day for 3 months, stopped for two months (called a washout period)
and then switched over to the women previously on placebo to further
verify the effects. Cholesterol was not affected by the Isoflavones,
but interestingly the levels of ghrelin fell significantly in the
women receiving soy Isoflavones. Inhibiting ghrelin, a hormone
released in the stomach that is a growth hormone releaser and an
appetite stimulator, may reduce hunger levels and aid weight loss.
The study is published in the July 2004 issue of The Journal of
Clinical Endocrinology and Metabolism
Commentary by Jerry Hickey, R.Ph.
Researchers at the University of Washington found that the hormone
ghrelin produced in the stomach, makes you hungry. Eating drops
your blood levels of ghrelin and your hunger is then shut down.
Interestingly, one of the effects of gastric bypass surgery for
extremely obese people is that they stop producing ghrelin and their
weight loss may become permanent. Normally when you loose weight
by dieting, the stomach releases even greater levels of ghrelin to
bring your weight back up (to an ideal level). Anything that safely
aids ghrelin control is likely beneficial.
Soy-Derived Estrogens Don't Seem to Increase Cancer Risk
Monkeys who had their ovaries removed (to stop their estrogen and
progesterone production) were placed on one of three diets for 3
years. One group received soy protein without Soy Isoflavones. A
second group received soy protein with 129mg of Soy Isoflavones
each day. The third group received equine (horse) derived estrogen
at a dose scaled to equal 0.625mg (in a woman) per day in a base
of soy protein (and without Soy Isoflavones).
Cell proliferation and progesterone receptor activity was much
higher in the breast and uterus of the group that received horse
estrogen than in the other two (the two other groups had the same
results). The subjects receiving Soy Isoflavones actually had
lower levels of estrogens in their blood than the other two groups
showing the Isoflavones were actually protective and not just
neutral. The result of receiving Soy Isoflavones showed that they
reduced the risk of breast cancer in this study and also protected
the uterus. The study is published in the July issue of The
Journal of Clinical Endocrinology and Metabolism.
Commentary by Jerry Hickey, R.Ph.
A recent study of almost 22,000 women in the Journal of the National
Cancer Institute shows that women with the highest dietary consumption
of Soy Isoflavones had a 54% decreased risk of developing breast
cancer and that the protection was the strongest in postmenopausal
women. A different study in postmenopausal women who were supplemented
with Soy Isoflavones (who didn't have soy as part of their normal
diet) had better cognitive skills, attention spans and memory recall
than women on placebo. The study was published in Pharmacology,
Biochemistry and Behavior.
Stroke and Dementia
Another study has been published linking stroke and loss of brain
function. According to this study the likelihood of developing
dementia after a stroke is high. In the first years following a
stroke it resembles Alzheimer's disease (the most common form of
dementia). Then it shifts over to resemble vascular dementia.
Researchers started followed 191 stroke patients 6 months after
their stroke for 4 years. 21.5 Percent of the patients (41 patients)
had developed dementia at the end of the four years. The study
confirms that dementia is a frequent consequence of stroke. The
study is published in the June 2004 issue of Neurology.