Cruciferous Vegetables for Thyroid Health

Have you ever heard of the cruciferous family of vegetables? You might not recognize the name, but I’m sure you’ll know the vegetables in the family.

I’ve received a lot of questions recently about cruciferous vegetables and how they tie into the thyroid’s health. So, I decided to give my thoughts on this family of veggies and how they fit into a healthy thyroid program.

The Cabbage Family

Cruciferous vegetables are related to cabbage and include:

  • kale
  • collard greens
  • Brussels sprouts
  • broccoli
  • cauliflower
  • bokchoy
  • turnip
  • rutabaga
  • horseradish
  • mustard (the seed, not the sauce!)
  • arugula
  • watercress
  • maca
  • radish
  • cabbage(of course)1

The great thing about these vegetables is the number of nutrients they contain, including carotenoids (like beta-carotene, lutein, and zeoxanthin), vitamin C, vitamin E, vitamin K, folic acid,minerals, and fibre2.

But what’s even more impressive is their content of sulphur-containing compounds called glucosinolates3. After we eat them, these chemicals get broken down into many other beneficial ones – indoles, nitriles, thiocyanates, and isothiocyanates4. The most-studied compounds include indole-3-carbonol (anindole) and sulforaphane (an isothiocyanate). You may not have heard of these before, but they provide some huge benefits!

Anti-Cancer Properties

The beneficial chemicals that we get when we eat cruciferous veggies have been shown in lab studies to have anti-cancer activity5. This is thought to happen because these compounds protect DNA from damage, inhibit carcinogens, cause apoptosis of cancer cells (programmed cell death), stop new blood vessel growth (which feeds the cancer cells), and stop cancer from spreading6.

Studies in humans have shown a benefit from consuming cruciferous vegetables in the prevention of prostate, colorectal, lung, and breast cancers7.

Thyroid Health

All over the internet, you can find references to how cruciferous vegetables are “goitrogenic”8. A goitrogen is a food or chemical that inhibits thyroid gland function. This can lead to an enlargement of the thyroid called “goiter”.

Cruciferous veggies are classified as goitrogens based on speculation and on one study, done on animals in 19839.

The animals that were fed large amounts of cruciferous vegetables had an increased incidence of hypothyroidism (underactive thyroid). What is often not mentioned is that this only occurred with animals that had a deficiency in iodine in the first place!

Animals with normal iodine levels did not get hypothyroidism, even with high cruciferous consumption. Further studies in humans have not been able to demonstrate increased risk of goiter or thyroid cancer from high cruciferous intake10.

The Best of Both Worlds

If you have issues with your thyroid but would like to take advantage of the awesome benefits of the cabbage family, there are two things to consider:

  • Are you low in iodine?
  • How can you prepare cruciferous veggies to minimize any potential goitrogens?

It’s possible to get tested for iodine to see if you’re low, but to maintain a healthy level, consumption of kelp, seafood, and eggs can help. For more information on the benefits of iodine, check out my last article11, 12. Making sure that you have adequate iodine will help prevent thyroid problems from high cruciferous intake.

Cooking your cruciferous veggies will prevent the glucosinolates in them from getting broken down. This will prevent these compounds from negatively affecting your thyroid, but it will also stop you from getting the anti-cancer benefit13. To get the most anti-cancer benefit out of these veggies, eat them raw or lightly steamed. If you find that you eat them a lot (several times each day), you may want to cook some of them more thoroughly as a precaution. Some of these veggies, like kale, collard greens, and mustard greens, contain compounds in them called oxalates, which can block mineral absorption14. Cooking them breaks down the oxalates and allows you to get your minerals.

The cabbage family offers us amazing health benefits. If we take a calm look at them, they are a great addition to the diet, even for those with thyroid problems.

If you enjoyed this article and think that others would benefit from it, please share, like, and/or leave your comments.

And for more daily news, articles, and videos on health topics from myself and other experts, please follow me on Facebook.

Until next time, this is Dr. Pat Nardini, ND, putting “Your Wellness First!

 

  1. http://en.wikipedia.org/wiki/Cruciferous_vegetables
  2. http://www.cancer.gov/cancertopics/factsheet/diet/cruciferous-vegetables
  3. http://en.wikipedia.org/wiki/Glucosinolate
  4. http://www.ncbi.nlm.nih.gov/pubmed/18458837
  5. http://www.ncbi.nlm.nih.gov/pubmed/11139137
  6. http://www.cancer.gov/cancertopics/factsheet/diet/cruciferous-vegetables
  7. http://lpi.oregonstate.edu/infocenter/foods/cruciferous/
  8. http://en.wikipedia.org/wiki/Goitrogen
  9. http://www.sciencedirect.com/science/article/pii/0308814683900742
  10. http://link.springer.com/article/10.1023%2FA%3A1020243527152
  11. http://www.healthscopepathology.com.au/index.php/functional-pathology/tests/urinary-iodine/
  12. http://foodwatch.com.au/blog/medical-diets/item/q-can-i-eat-cruciferous-vegetables-eg-cabbage-cauliflower-broccoli-if-i-ve-had-my-thyroid-removed-or-are-taking-thyroxin-tablets.html
  13. http://www.ncbi.nlm.nih.gov/pubmed/2419242?dopt=Abstract
  14. http://en.wikipedia.org/wiki/Oxalate

 

If you have questions about naturopathic medicine, or you’d like to take your first step into the world of naturopathy, contact us at Nardini Naturopathic, and let’s book an appointment.

Yours in health,

Dr. Pat Nardini, Naturopathic Doctor

320 Danforth Ave suite 206,
Toronto, ON, M4K 1N8

-https://g.page/NardiniNaturopathicDanforth

Dr. Pat Nardini, ND is a licensed doctor of naturopathic medicine in Toronto, Ontario. He offers science based natural health solutions with a special focus on thyroid conditions.