Reminder: Soy may cause AF
This is a repeat caveat about soy and the potential to cause arrhythmia as well as thyroid problems which can then be related to AF.
For new readers who rely on soy as a protein source and are experiencing arrhythmias, this reminder offers an important consideration.
The FDA allows products containing soy protein to carry a claim stating that they protect against heart disease. But, the principle isoflavone in soy, genistein, has been shown to cause heart arrhythmias.
Researchers have found that genestein interferes with potassium in the heart “suggesting the potential for soy isoflavones to cause heart arrhythmias”
Source: Chiang CE et al. Genistein inhibits the inward rectifying potassium currents
J Biomed Sci, 2002, 9, 321-326
Quoted from
The Whole Soy Story… the dark side of America‘s favorite health food
by Kaayla Daniel, PhD, CCN
(PhD in Nutritional Sciences and Anti-Aging Therapies)
www.wholesoystory.com
Additionally, as soy relates to thyroid dysfunction, it can also contribute to arrhythmias:
There is 60 years of studies relating soy to thyroid problems including Hashimoto’s.
[
www.westonaprice.org]
At Mary Shoman’s website – She talks about both Oprah and well-known Gynecologist Christiane Northrup, MD, both having thyroid problems after jumping on the soy band-wagon.
[
thyroid.about.com]
[
thyroid.about.com]
There was a recent complaint in another blog about protein drink powders and other protein products using soy but not labeling properly. Be sure you read the fine print.
Soybean-related foods
Included in the category of soybean-related foods are soybeans themselves as well as soy extracts, and foods made from soy, including tofu and tempeh. While soy foods share many common ingredients, it is the isoflavones in soy that have been associated with decreased thyroid hormone output. Isoflavones are naturally-occurring substances that belong to the flavonoid family of nutrients. Flavonoids, found in virtually all plants, are pigments that give plants their amazing array of colors. Most research studies in the health sciences have focused on the beneficial properties of flavonoids, and these naturally-occurring phytonutrients have repeatedly been shown to be highly health-supportive.
The link between isoflavones and decreased thyroid function is, in fact, one of the few areas in which flavonoid intake has called into question as problematic. Isoflavones like genistein appear to reduce thyroid hormone output by blocking activity of an enzyme called thyroid peroxidase. This enzyme is responsible for adding iodine onto the thyroid hormones. (Thyroid hormones must typically have three or four iodine atoms added on to their structure in order to function properly.)
[
whfoods.org]
