No wonder menopausal women get cranky.
Not only did a new University of Miami study find that soy doesn't help, the women in the study who took soy pills reported more hot flashes plus -- to add insult to injury -- constipation.
As for flaxseed, another recent study found that eating flaxseed daily did nothing for relieving hot flashes -- unless you count bloating, diarrhea and nausea as a way to distract yourself from them.
See why older women are cranky?
Postmenopausal women began turning to soy as a safer, dietary source of estrogen after 2002, when the results of the Women's Health Initiative found that traditional hormone replacement therapy carried health risks, particularly cardiovascular disease. The thinking at the time was that Asian women eat a diet rich in soy and they have lower rates of breast cancer and bone loss, so why shouldn't Western women just take soy supplements and get the same benefits?
The research supporting such reasoning has been sketchy up to now. But a new study, reported in the August issue of the Archives of Internal Medicine, followed 248 women between the ages of 45 and 60 for five years to see if taking soy supplements delayed the bone loss associated with menopause.
All of the women were within five years of the start of menopause and had a bone density score of -2.0 or higher at the lumbar spine or total hip -- meaning they had suffered some bone thinning, or osteopenia. (A score of -2.5 is considered osteoporosis.)
The women were randomly divided into two groups and given either a placebo or 200 mg. daily of soy isoflavone tablets.
The result: Bone density wasn't any higher in the women taking soy supplements. The researchers said they found no significant differences in any measurements of bone density between the two groups.
On the other hand, nearly 50 percent of women taking soy had hot flashes, compared to just 32 percent of the placebo group. The soy group also reported more constipation.
So not only didn't the soy decrease hot flashes, it produced uncomfortable, unfortunate side effects.
As for flaxseed, it was also thought to be beneficial because it contains phytoestrogens -- a form of plant estrogen that mimics the effects of animal estrogen. Shouldn't it help with hot flashes?
Uh, no. Flaxseed was no better than a placebo at reducing hot flashes in postmenopausal women, according to a study presented at the June meeting of the American Society of Clinical Oncology.
Researchers from the Mayo Clinic in Rochester, N.Y., followed 188 postmenopausal women. Half were given a daily flaxseed bar for six weeks, half got a similar bar without flaxseed. After six weeks, about a third of each group reported a decrease in symptoms, meaning the flaxseed bar did no better than a high-fiber bar.
However, both groups also reported suffering from bloating, diarrhea and nausea, probably from the increased amount of fiber in each bar.
"Flaxseed may be a highly touted supplement for many ills, but according to our randomized study results, it is not effective for hot flashes," said lead researcher Sandhya Pruthi in a press statement.
As for other ways women can prevent bone loss after menopause: Eat high-calcium foods like nonfat yogurt, cooked spinach, tofu and canned white beans. And don't forget regular weight-bearing exercise like walking, dancing, gardening, yoga and lifting light weights.
Plus, if you go outside for regular walks, you'll also be getting vitamin D -- something else that's important for strong bones.
It might even help ward off some crankiness.
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