There are a number of green smoothie benefits that often seem too good to be true. Can they really improve your health as much as the claims state? Or is it a load of exaggerated internet marketing that’s spiralled into fiction?


In this article – we review the scientific evidence and summarise the nutritional facts so you can decide for yourself whether they live up to the hype…


Kale and spinach smoothie benefits are often said to be increased energy levels, clearer skin, and weight loss.  These bold health claims along with the many celebrity fans have helped convince thousands of people to consume more leafy greens. Because let’s face it, who doesn’t want to feel more energised and look glowing to boot?


But in a world full of miracle health promises, clever marketing campaigns, and magical supplements, it’s easy to become cynical. So, when it comes to green smoothie health benefits, let’s separate nutrition fact from fiction…


Kale Smoothie Benefits

Kale is packed with vitamin K – 50g (less than a cup) provides over 5x our daily needs. Adding a handful of these leafy greens to a smoothie will smash your requirements. This nutrient keeps bones strong and helps wounds to heal quickly as well as aiding calcium absorption.


It’s also rich in vitamin A – just five kale leaves provide over 2x the recommended daily allowance (RDA). As well as containing antioxidant properties, it’s also good for our eyes, skin, and hair. Vitamin A is important for sebum and natural oil production, which keeps hair moisturised and looking shiny.  It also helps collagen production, which helps keep our skins looking fresh and youthful. This may be why green smoothie fans report clear and glowing skin.


A cup of kale (50g) also contains 100% of your Vitamin C needs. Although it has antioxidant properties, Vitamin C (also known as Ascorbic acid) is more renowned for supporting the immune system.


Spinach Smoothie Benefits

Spinach isn’t as rich in vitamins as kale but it’s still highly nutritious. A 50g serving would provide 3x your vitamin K needs, 98% of vitamin A, and 23% of vitamin C. This makes it a healthy addition to any smoothie.


Spinach is also a good source of folate (aka folic acid) providing 49% of your RDA. This nutrient supports growth at the most basic level – DNA. Whilst it’s well known for being an essential vitamin for pregnant women, it also releases serotonin, acting like a mild but natural antidepressant. However, kale isn’t a big source of this nutrient containing around 8 times less than spinach.


Ten spinach leaves contain 10% of our RDA of Iron. This probably isn’t as much as the Popeye endorsements would have you believe but it does contribute to keeping your blood cells healthy. These, in turn, keep everything else in the body healthy. Kale has about half the amount of iron as spinach does so isn’t a great source of this either.


Now let’s look at green smoothie benefits relating to energy levels, weight loss, and skin.


Do Green Smoothies Increase Energy?

Is there such a thing as an energy-boosting green smoothie? Many people rave about all the extra energy they get from drinking spinach and kale smoothies. But a single leaf of spinach contains just 2 calories which equates to barely any energy. So how does that work?


Well, calories aren’t the only thing that matter. Green smoothies are bursting with vitamins and minerals which support functions like converting carbs and fat into useable energy. Without sufficient micronutrient levels, we can feel tired or lethargic.


Despite eating three meals a day, many people are deficient in these essential vitamins and minerals.  Modern western diets often lack key nutrients, so blending up some leafy greens into our smoothies can help rebalance this. But so could adding a portion of veggies to your dinner or swapping that lunchtime sandwich for a salad.


Green smoothies also tend to contain fruit which plays a big role in fuelling our bodies.  The sugars from banana, mango, pineapple, etc are easily absorbed and can quickly boost our energy levels. So, while this may be beneficial for people who often feel tired, it’s something that simply eating more fruit would help with.


Love geeking out on nutritional info? Then check out our infographic about the health benefits of banana smoothies.


Benefits of Green Smoothies for Weight Loss

Is there any point in consuming a kale or spinach drink for weight loss? Well, green smoothies aren’t a miracle solution but they may help people to lose weight as part of a balanced diet and active lifestyle. Here are some of the possible ways they can help…


  • Increases fibre consumption – which helps people feel fuller so they’re less likely to overeat.
  • Can lower calorie intake – when used as a meal replacement, people can reduce their calorie intake while still consuming vitamins and minerals.
  • May reduced cravings – consuming a wide range of nutrients can make people feel more satisfied and reduce their tendency to overeat.
  • Less bloating – consuming more plant-based foods instead of processed alternatives can reduce stomach bloating which makes people appear slimmer.


These are some of the possible ways that green smoothies may aid weight loss. One study did find a link between green smoothie consumption and decreased waist circumference. However, it involved a very small number of participants (29) so more research is needed to establish proof.


How About Skin-Related Benefits?

One of the most commonly reported green smoothie benefits is better skin. Clearer, brighter, more glowing skin. However, there isn’t any scientific evidence to support this.


One study evaluated the effect of daily smoothie consumption on skin appearance. A small group of 34 participants consumed a smoothie containing 25mg of carotenoids per day for 4 weeks. Before and after photos were taken, then a separate group was asked to choose which photos looked healthier. However, they didn’t find a significant difference in the results which indicates there was no skin benefit.


If you’re someone who doesn’t consume much fruit and veg, then your skin may benefit from a green smoothie. But we wouldn’t recommend green smoothies for acne as the extra sugar may make things worse rather than better. A pure vegetable smoothie should be ok but since there’s no proven benefit, you’re better off sticking with evidence-based approaches.


Green Smoothies Vs Raw Vegetables

In a perfect world, whole veggies are the ideal. Research has found that eating whole foods is more filling than blended equivalents, so you’re less likely to snack later in the day. But we live in the real world – a time-poor and nutrient-starved one.


If you don’t have the time or inclination to prep and eat fresh veggies, then green smoothies are a quick and easy way of upping your intake of leafy greens and other good stuff. We don’t need to be perfect, we just need to be better.


What’s The Deal With Oxalates?

You may have heard green smoothies linked with kidney stones or similar stone formations in the body. It’s true that spinach has higher oxalate levels than other leafy greens, but this doesn’t mean drinking green smoothies will cause oxalate build up. There are a variety of factors like genetic predisposition and gut health that influence this.


However, it’s a great reminder that we should consume everything in moderation.  Kale has much lower levels of oxalate, so rotate your greens, and use veggies that are in-season to add variety.


Kale & Spinach Smoothie Benefits