Posted in Nutrition 101, Nutrition

Unless you’ve spent the last few years hanging out with nomadic tribes in Africa, you’ll know that green smoothies are well and truly a thing. In fact it’s almost impossible not to walk into a café without there being some sort of green smoothie on the menu. But are they really good for you?

Green smoothies vary in intensity from your tropical, easy-drinking green, to your more hard-core ginger, turmeric and whole lemon variety. But one thing they all have in common is that they typically have a base of raw spinach, rocket, celery and parsley – oxalate rich foods that could be playing havoc with your health.

So what are oxalates?

Oxalates are small molecules that look and feel like crystals, and are extremely acidic. Oxalate and its most acidic form oxalic acid are organic acids that are formed through the foods we eat, from fungal infections or from poor metabolism or digestion. All of which is compounded, if you are one of the 20-25 per cent of the population who have a genetic tendency to naturally produce them.

Why are oxalates a problem?

They are painful. Often excruciatingly so. Too many oxalates in the system results in a pain that is similar to having glass shards in the body. Think kidney stones. It is estimated that up to 90 per cent of kidney stones are due to high oxalates in the diet, with one in ten people suffering from kidney stones at some point in their lives.

But oxalates can lodge themselves in other parts of the body as well in our bones, our teeth, our eyes, our arteries, our lungs, the thyroid and even in our brain. Usually this occurs without us knowing that this is the problem.

Aside from the pain they cause they also act to bind metals, particularly mercury and lead, trapping the toxins in the body and preventing elimination for years, even decades.

So is it safe just to avoid raw spinach? Unfortunately no. Seeds, nuts, blueberries and chocolate all contain high levels of oxalates. And, cooking your leafy greens won’t make much difference either, as it has a relatively small impact on the oxalate content of foods.

What can we do about it?

First of all be mindful of the amount of oxalate rich foods you eat. The odd green smoothie is certainly not going to kill you, in fact it’s a great way to up your nutrients, but our bodies probably weren’t designed to have one every day. Enjoy green leafy vegetables in moderation, and think about making those almond milk lattes a treat, not a daily occurrence.

For proper elimination of oxalates to occur we must maintain a good digestive system, which means maintaining good gut health by incorporating fermented foods and/or probiotics into our diet.

If you feel your body could be dealing with too many oxalates, then it is important to consult with your health practitioner. They can guide you on how best to completely remove the oxalates from your system, and can recommend a low-oxalate diet for on-going health.

You can learn more about the potentially harmful effects of green smoothies, and the specific greens that are the culprit, here.

If you think your favorite green smoothie could be playing havoc with your health, try something new. Check out some spinach-free smoothie options here.

Angela Merrie

Angela Merrie is the founder of Pretty Damn Good For You, inspiring people to live better through nutritionally balanced, whole food, plant-based recipes. Angela is on the board of several companies that invest in environmental projects globally. She holds a degree in Fine Art, and recently graduated from the Institute for Integrative Nutrition (IIN) in New York as a Health Coach and Holistic Nutritionist. Find out more at and follow @angela_merrie on Instagram.

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