Is Kale Bad for You? – What You Should Know

Published:

August 13, 2020

Image via Shutterstock.

Nina Zorfass, IIN Content Editor

How much kale is too much?

In general, kale is considered a healthy food when eaten in moderation and in balance with other foods and food groups. This leafy green can be enjoyed sautéed in olive oil, blended into smoothies, tossed in a kale salad, or even baked into kale chips!

Because of its versatility, it’s not difficult to consume kale for breakfast, lunch, and dinner, but it’s important to consider that the amount of kale you consume may impact your health, depending on any health conditions you have and how your digestive system tolerates this cruciferous vegetable. 

What to look for when eating kale

Kale has become hugely popular – and for good reason! Kale’s health benefits are abundant as it is high in water-soluble vitamin C and fat-soluble vitamins A and K and is also a great source of fiber, all of which help to prevent heart disease and promote heart health.

Kale is also known for containing certain compounds called glucosinolates. These sulfur-containing compounds are found in all cruciferous vegetables, and research has demonstrated that they can offer protective qualities against cancer, such as protecting against damage by free radicals. However, these compounds are only found in raw cruciferous vegetables, like raw kale, and are degraded upon heating and cooking.

When you eat raw kale, glucosinolates are broken down into a compound called thiocyanate. This compound can interfere with the thyroid’s ability to take in iodine, which is required for proper thyroid function. Another compound found in raw cruciferous vegetables is progoitrin, which can interfere with thyroid hormone synthesis, impacting important functions of the thyroid, such as blood sugar control and regulating your metabolism.

For those with hypothyroidism, it’s recommended to watch the amount of raw kale and other cruciferous vegetables you’re consuming. If you have a heart condition that requires a blood thinner, you may want to be mindful of your vitamin K intake. Vitamin K promotes blood clotting, while blood thinners work to slow blood clotting. This means that consuming high amounts of vitamin K, such as kale, spinach, and Brussels sprouts, can interfere with this medication.

If you don’t have any thyroid or clotting issues, though, that’s not permission to eat as much kale as you want! However, you would need to eat a whole lot over a long period of time to see these kinds of negative effects on your health.

Should I eat raw or cooked kale?

Raw kale is entirely safe to eat, but make sure it’s rinsed and dried thoroughly before eating! Kale is on the Dirty Dozen list, which means it’s often grown with pesticides, and the residue from these pesticides must be rinsed off completely to ensure you’re not consuming them. Also, as with any fresh fruit or vegetable, there’s always the possibility of human contamination during harvesting and transporting, so it’s best practice to rinse your produce before eating. 

Whether you decide to eat raw kale, cooked kale, or a bit of both, it all depends on your bio-individuality, the understanding that what works best for you won’t necessarily work for others. This applies to all areas of life, but it’s especially true when it comes to diet and which foods work for your body.

If you experience hypothyroidism, it may be enough for you to say, “I’m never eating raw kale and only eating cooked kale.” If you don’t experience hypothyroidism but have other health issues, such as leaky gut syndrome or general gut dysfunction, eating high amounts of this fibrous vegetable can be tough on your gut lining and digestion, especially when raw.

Many people tolerate this kind of vegetable better when it’s cooked, which still packs a nutritional punch! Here are some ways you can prepare cooked kale: 

  • Bake it – Kale becomes crisp and crunchy in the oven to make a much healthier version of chips!
  • Sauté it in a healthy fat – Kale contains fat-soluble vitamins A and K, which means they are best absorbed when paired with fat. Throw kale into a pan with olive oil, ghee, or avocado oil to create a simple side dish for your next dinner.
  • Add it to your favorite soups or stews – Kale is a perfect leafy green to add because it softens quickly while still maintaining its consistency, making it an easy and delicious way to get more greens into your diet!

Pros and cons of raw vs. cooked kale

Determining the pros and cons of eating raw or cooked kale will also come down to your bio-individuality, but here are some of the most common:

Pros of eating raw kale

  • It’s quicker to prepare.
  • It adds bulk to smoothies and salads.
  • Glucosinolates – cancer-preventing properties – are still intact.

Cons of eating raw kale

  • It can potentially exacerbate existing thyroid problems, leading to blood sugar control and metabolism issues.
  • It can potentially exacerbate existing blood clotting issues or lessen the impact of certain medications.
  • It can potentially cause stomach pain, constipation, or bloating.

Pros of eating cooked kale

  • It’s easier on the digestive system and gut.
  • Fiber content remains intact.
  • Fat-soluble vitamins are better absorbed (if cooked with fat).

Cons of eating cooked kale

  • It takes longer to prepare.
  • Glucosinolates are degraded. 

So is kale bad for you?

Only you can answer that! When it comes to living a healthy life, this is only a small piece of the larger picture. In addition to kale – or any other leafy green you consume – it’s best to focus on eating a balanced diet full of foods from other food groups, such as complex carbohydrates, healthy fats, and quality protein (plant- or animal-based)!

Also consider this: You can eat as much kale as you want, but if other areas of your life are unfulfilled – such as your home environment, relationships, or career satisfaction – that daily kale smoothie won’t promote health in your body as much as it could if you were living a balanced life. An IIN education focuses on just that: Finding balance in every area of your life to promote optimal health and well-being in body, mind, and spirit. Learn more about the innovative health coaching curriculum that can help you achieve a balanced life and teach others to do the same.

Curriculum Guide - Blog Page

Get The Document

GET OUR CURRICULUM GUIDE

By clicking 'Get The Guide', I consent to Integrative Nutrition and its affiliates contacting me by email at the address provided and/or by telephone at the number provided (by live, automated, or prerecorded phone calls or text messages) about its courses. I understand that my consent is not required for enrollment and may be withdrawn.