Foods which may adversely affect your thyroid

Many commonly eaten, otherwise nutritious foods, have been reported to have an adverse affect on thyroid functioning. I think it is helpful to be aware of this possibility, even if you've eaten these foods for many years.

The most effective (and least expensive) way to test whether you may be sensitive to these foods is through an elimination diet. This requires that you avoid the suspect food for at least a month and then eat it several times in a week and carefully note whether you had an adverse reaction when you added it back into your diet.

Cabbage family veges.

The foods most widely reported to supress thyroid functioning are vegetables in the cabbage family. (This implies that people with hypothyroidism should eat cabbage family foods in moderation or even avoid them. However, people with hyperthyroidism may actually benefit from the thyroid-suppressing effect of the cabbage family.) Here is an explanation from a book with the cheerful title Eat Right or Die Young by Dr. Cass Ingram:

"Certain foods contain chemicals which block the production of thyroid hormone, particularly cabbage, broccoli, rutabaga, cauliflower, kale, Brussels sprouts, watercress, and peanuts. Cooking partially inactivates the interfering chemical, known medically as a goitrogen. Thus, in most cases it is wise to eat these foods cooked. Raw peanuts or soybeans should never be eaten. Fortunately, peanut butter is heated to a high enough degree that the goitrogens are destroyed."

Milk and dairy products.

God designed cow's milk to turn a scrawny baby calf into a 1,000+ pound steer in a few months. In spite of the propaganda of the Dairy industry, many nutritionists warn that milk is hard on the human body! In his book, Fit for Life, Harvey Diamond states that milk is a major contributing factor to thyroid problems, especially since modern dairy products often contain traces of antibiotics such as penicillin and hormones which place an even greater burden on your endocrine system. Dr. Norman Walker, M.D., in his book Become Younger, explains the impact of dairy as follows:

"Among the elements or ingredients which the Thyroid uses to make thyroxine is a protein known as casein. The body manufactures its own casein out of the atoms present in our food, in the same manner that the cow generates the casein in her milk from her feed. Casein is one of the important components of milk, but when cow's milk is used by humans of any age, it is not digested properly or completely under any circumstances. That is the reason why the use of milk not only creates a great amount of mucus in the system, but also has the tendency to disrupt the function of the Thyroid gland. The casein in cow's milk is 300% more concentrated than that in mother's milk. When cow's milk is pasteurized or cooked by boiling, the casein is changed still worse than in its raw state."

I had always loved milk and regularly drank several glasses a day. So I was reluctant to drop dairy. But almost two years after I had made other diet changes, I quit eating cheese and substituted rice milk on my cereal. The difference was real! My stuffy nose cleared and my monthly cramps vastly improved. (Dairy is also reputed to be a factor in asthma.) Why not experiment by dropping dairy for at least two weeks? It may make a real improvement in your health!

Soy products.

Following a tip from Prevention magazine, I began in October to eat 3 ounces of tofu daily, mixed with orange juice. While the soy's natural estrogen may have helped my late 40's women issues, I believe it had an unexpected side effect: I went hypothyroid. Soy is a goitrogen known to depress thyroid functioning. I eat tofu only occasionally now.

Soy Online Service (SOS) is a website from New Zealand which publishes several articles which warns of the effects of soy consumption on the thyroid.

For more information on soy, the Soy Connection (a soy industry newsletter) has published several articles.

Kelp and other sea vegetables

While a small amount of seaweed can be beneficial to the thyroid, an excess can damage thyroid functioning. According to Annemarie Colbin, in her excellent book, Food and Healing:

"Thyroid problems can arise from an excess of iodine as much as from a deficiency. Considering that we are already ingesting large quantities of this mineral because of its presence in fertilizers and table salt, the situation definitely bears watching. Early warning symptoms of an excess of iodine might include underweight, hyperactivity, rough skin, acne, mental and emotional imbalances, and a 'spaced-out' feeling."

Refined sugar.

Like many people with thyroid dysfunction, my body seems to be especially sensitive to refined sugar. Even a small piece of cake or candy sets my cheeks burning as my body reacts with alarm to almost any sugar I eat. In his book, Eat Right or Die Young, Dr. Cass Ingram explains that high sugar intake can indeed adversely affect the thyroid:

"At (a high) level of sugar intake, there is a risk of damaging or even destroying the adrenal and thyroid glands. These delicate glands must work overtime to help the body deal with excess sugar. After awhile under the pressure of constant bombardment of refined sugar, these glands literally burn out. To be sure, the glands are capable of regenerating and their function can return if you make the appropriate dietary changes and get off the sugar. There is a risk for permanent damage if you continue your sugar consumption. The more sugar consumed over the years, the more likely it is that you will have burned out a portion of your adrenal and thyroid glands."

My Favorite Books
I read a lot, but these are the books I trust. If you're feeling lousy and are confused about food choices, these books will give you hope and new direction. If this web site has been helpful to you, you can help us by ordering a book now through Amazon. Here's wishing you good health!

Prescription for Nutritional Healing is a wonderful reference book, written by an MD and a certified nutritional consultant. The book suggests sound nutritional strategies for coping with more than 250 diseases, including hypothyroidism. You'll turn to this book again and again!

In the Complete Book of Juicing, Dr. Michael T. Murray (one of the world's leading authorities on natural medicines) reveals how fresh fruit and vegetable juices can help combat cancer, aging, arthritis, high cholesterol, high blood pressure, kidney stones, ulcers, and other health conditions. Over 150 easy recipes included.

I love the balanced approach presented by Annemarie Colbin in Food and Healing. She analyzes the strengths and weaknesses of a number of alternative diets, explains the remarkable healing qualities of specific foods, and describes how to tailor a diet approach that is right for you.

Fit for Life changed the way I think about food. If you're confused about what to eat, you'll appreciate the simple, natural advice in this book. This is the book I buy and give to friends who ask me the secret of my good health.

Living Well with Hypothyroidism is a great resource for those of us dealing with the condition. In her book Mary Shomon discusses symptoms, conventional treatments and alternative treatments, including new research on the value of adding T3 to the more traditional T4 hormone replacement. Very helpful!

Fresh Vegetable and Fruit Juices is the first and still the best book on why and how juicing restores health. The book was written by Dr. Norman Walker, who literally invented juicing and reportedly lived well past 100. This affordable little book contains very specific advice for treating hypothyroidism and many other conditions, and is available in most health food stores.


The Thyroid Health Homepage has provided this material for informational purposes only. We do not prescribe and we do not diagnose. If you use the information on this website without the approval of a health professional, you prescribe for yourself, which remains your constitutional right, but neither the author nor the Thyroid Health Homepage assume any responsibility.

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