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The Truth About Soy Protein Isolate

A few summers ago, I unexpectedly ran into an old friend. During our conversation, he asked me to try a new weight-loss shake he was marketing. To humor him, I took one of his samples.

After I got home, I looked on the back of the package and read the list of ingredients. The first one listed? Soy Protein Isolate.

Uh oh.

I already knew soy was bad for you. But I didn't know the extent of it. Here is a list of long-term health risks I found:
    • Asthma
    • Cancer - Breast, Liver, Uterine, Colon, Thyroid, Pancreas, Prostate
    • Brain and Nervous System Damage
    • Infant Abnormalities
    • Thyroid Disorders - Hypothyroidism
    • Kidney Stones
    • Immune System Impairment
    • Severe Food Allergies
    • Impaired Fertility
    • Harm During Pregnancy and Nursing
    • Erectile Dysfunction
    • Breast Enlargement in Men (Gynecomastia)
    • And much more
      According to one health website, soy protein isolate mimics estrogen so well it can cause breast enlargement in men. It also can cause erectile dysfunction, decreased facial hair, mood swings and lowered sperm counts.

      As for the weight-loss shake, the main ingredient is soy because it's a cheap source of protein. The priority is profit margins, not your health.

      And don't let anyone try to tell you soy protein isolate can be modified, so that all the bad stuff is taken out and the good stuff is left in it. I'm an advocate of getting your nutrition from food as close to the way it is found in nature.

      So before you decide to try any shake or health supplement, make sure to first do your homework.

      You can choose to ignore the evidence about soy or you can embrace it. I hope you make the right decision. Why make yourself a guinea pig?

      Recommended Links:

      The Dark Side of Soy

      'The Whole Soy Story' by Dr. Kaayla Daniel

      NCBI: Effects of Soy Protein on Thyroid Function

      Low-Carb Dieter Beware: Protein Shakes Not A Panacea

      LiveStrong: The Dangers of Soy Protein Isolate

      Doctor Warns: Eat This and You’ll Look 5 Years Older

      Soy: The Deadly Poison - An Interview