Concern #3: Soy is bad for my thyroid.
Verdict: The available research suggests that soy may not affect thyroid function, especially in those who have a normal thyroid.
However, soy may be dangerous for those who already have an existing thyroid problem and take medications for their thyroid. This is because soy products may interfere with how the body absorbs the medication in the GI tract, making it less effective. A general tip for those taking thyroid medication would be to wait a few hours between taking your thyroid medication and consuming any soy products as soy tends to alter how your intestines absorb the medication. Talk to your physician about soy and any thyroid medications you may be taking.
Soy Foods: Bad, Better, Best
Like all foods, you want to consume soy in moderation. One to two servings of whole and fermented soy foods is recommended. One average serving is a half-cup of tofu or 1 cup of soy milk.
But not all soy products are created equal. Thanks to savvy marketing and nutritional buzzwords, most of us think we are automatically doing a good thing for ourselves when we choose soy foods. Unfortunately, this isn’t always true. Make the right selections to ensure you’re getting the best and purest forms of nutrition from soy foods and soy products.
Avoid: Soy Burgers, Soy Energy Bars and “Frankensoy” Products
Soy burgers and soy energy bars are not your best choice. Why? Because these foods are made of processed forms of soy. Look for the words “soy protein” on the label – this means the soy it contains is processed. When soy is processed, the nutrients are stripped away. When it comes to this, nutritionists consider it to be a “ghost” of a health food.
Other highly processed "frankensoy" products look and taste just like frankfurters, steak strips, cheese and other foods. Avoid these. Foods like these are also likely to be loaded with added sugars, fats and refined flours.