10% off £25 OR 15% off £35


10% off £25 OR 15% off £35


Use code:JOY

women pouring a smoothie

What is the smoothie diet?

11 Nov 2021 • 4 min read

Heard of the smoothie diet but not sure what all the hype is about?

Interested in giving it a go but not sure if it’s good for you? Find out all the information you need to know in our guide.

In this article, you’ll learn about

  • What the smoothie diet is
  • If the smoothie diet is healthy
  • If smoothies are a good way to lose weight
  • What the 21 day smoothie diet is
  • If you can drink two smoothies a day
  • Benefits of the smoothie diet
  • Ways to make sure you’re doing it right
  • Smoothie recipe ideas
  • If the smoothie diet is suitable for everyone

What is the smoothie diet?

The smoothie diet is generally where two out of three meals a day are smoothies.

Supposedly, the smoothie diet should be done on a 21 day cycle, with one week where ‘normal’ eating may resume – aka, three meals a day that aren’t a drink.

8 benefits of the smoothie diet

So, what are some of the benefits of the smoothie diet?

From potential nutritional benefits to lifestyle enhancements, find out some of the reasons people go on the smoothie diet below.

  1. May be high in antioxidants

Fortunately, a lot of fruits and vegetables contain antioxidants, which are beneficial for helping your body defend against free radicals, which can cause cell damage.

These fruits and vegetables are particularly worth adding to your smoothies for this reason:

  • Blueberries
  • Strawberries
  • Goji berries
  • Raspberries
  • Kale
  • Red cabbage
  • Green broad beans
  • Beetroot
  • Spinach1
  1. You may consume more vitamin C

Another benefit of the smoothie diet is the vitamin C you will consume from the fruits and vegetables used in the smoothies.

Here are some of the best ingredients to add to your super smoothies to give them a boost of vitamin C:

  • Blackcurrants
  • Oranges
  • Limes
  • Lemons
  • Berries
  • Kiwi fruit2
  1. High fibre intake

Not only do you get antioxidants and vitamin C from smoothies, but you also get plenty of fibre!

This is super important for keeping our digestive system healthy and preventing constipation.

As well as this, high fibre diets have been associated with a lower risk of heart disease, stroke, type 2 diabetes and bowel cancer.3,4

Foods especially rich in fibre that you could add to your smoothies include:

  • Wholegrain oats
  • Berries
  • Pears
  • Melon
  • Oranges
  • Broccoli
  • Carrots
  • Nuts
  • Seeds5
  1. Phytonutrients from fruit and vegetables

Not sure what they are?

Essentially, phytonutrients are natural plant compounds that are produced to keep them healthy, as well as protecting themselves from the heat of the sun and insects.

But they can also support us humans too.

Phytonutrients have been found to have both antioxidant and anti-inflammatory properties that can benefit our immune system, eye health, heart health, and detoxification.6,7

  1. Easy to follow

Another benefit of the smoothie diet that has increased its popularity is how easy it is to follow – especially since modern life can be so busy and complicated.

You just have to educate yourself on the nutrients you need to add to your smoothies and then make sure to get any other nutrients you can in your regular meal of the day.

  1. Quick to prepare

In a similar vein, another benefit of this particular diet is that it is quick and easy to prepare.

Once you’ve chosen your key ingredients, washed and prepared them, all you need to do is whizz it all up in a blender and then drink it – happy days!

  1. Less calorie counting than other diets

In addition, diets that are largely focused on calorie counting can be time-consuming and confusing.

Whereas with the smoothie diet, you’ll know that you’ll be taking in fewer calories without having to measure everything out and keep it logged.

  1. Pre-made shopping lists

If you decide to go with the original 21 day smoothie diet book, you’ll also have access to pre-made shopping lists, saving you more time and energy throughout the week.

4 ways to make sure you’re doing it right

Read on to make sure you are getting the smoothie diet right...

  1. Make sure to have one nutritious meal a day

Although you can get a lot, you can’t get all the essential nutrients to fuel your body in a smoothie.

This makes it super important to ensure the one proper meal you do have a day is packed with plenty of nutrients.

Be sure to include a good quality source of protein, whether that’s lean meat, eggs or tofu, for example, a serving of unrefined carbohydrates, some healthy fats and plenty of veggies!

  1. Watch your sugar intake

While the majority of your meals will contain natural sugars, be sure to watch out for any added sugars.

This is because consuming a high level of sugar everyday can lead to blood sugar spikes and potentially even fat storage – according to Rob Danoff, a family medical physician.8

One solution to this could be to avoid adding more than one cup of fruit to each smoothie, and to use unsweetened milk or water as the liquid.

In addition to this, if you’re adding protein powder, try to use one that is low in sugar.

  1. Get enough protein in

As well as low calorie diets being effective for weight loss, high protein diets have also been highlighted as effective by various different scientific studies.9,10

So why not capitalise on both?

To take advantage of this, try adding some protein powder to your smoothies, as well as using milks that are naturally high in protein.

Or if you’d like to shake things up a tad, why not add some oats to your smoothie? They’re considered a source of low-cost protein with additional nutritional value.11

  1. Add some healthy fats

And finally, it’s important to include some healthy fats in your smoothies as well.

Fat is especially beneficial for absorbing certain vitamins, like vitamin A, vitamin D and vitamin E.12

Interestingly, swapping out saturated fats for unsaturated fats can help to lower your cholesterol levels too.13

So for the best kinds of fats in your smoothies, here’s what to choose:

  • Avocados
  • Nuts
  • Nut butters
  • Flaxseed
  • Walnuts
  • Soymilk
  • Tofu14

Is the smoothie diet suitable for everyone?

While the smoothie diet should generally be safe for people to try, there are risks for people with certain conditions or people taking certain medications.

For example, since this diet is higher in sugar than some other diets, it is not recommended for people with diabetes.15

Equally, if you’re looking to build or maintain muscle, this may not be the diet for you as it could lead to a loss of muscle mass.

6 smoothie ideas

Find out our top smoothie recipes.

  1. Vibrant tropical smoothie


  • 1 banana, cut into chunks and frozen (at least overnight)
  • 3 tbsp mango chunks
  • 3 tbsp pineapple chunks (can be canned in juice, drained)
  • ½ tsp turmeric
  • Pinch of freshly grated or ground ginger
  • 250ml coconut milk

How to make the vibrant tropical smoothie


Place all of the ingredients in a blender or food processor and whizz up for at least 30 seconds until smooth.


Pour into a mason jar or glass and drink straight away while chilled.


  • 2 cups spinach
  • 1 banana
  • 1 orange
  • 1 beetroot
  • 1 tsp honey

How to make a beetroot & spinach smoothie


Blend all ingredients together until smooth.


Add a handful of ice will make the smoothie thicker as well as the perfect chilled temperature to enjoy immediately.


  • 1 banana
  • 4 strawberries
  • 50g of blueberries
  • 1 tbsp of oats
  • 30g of cashews
  • 200ml of almond milk

How to make the deliciously Ella smoothie


Simply blend all the ingredients until smooth and creamy!


Try using frozen banana or berries for a nice cold smoothie.


  • 200g blueberries
  • 1 tsp oat bran
  • 2 tbsp Greek yoghurt
  • 150ml milk (or dairy free alternative)
  • 2 tbsp Manuka Honey
  • 2 tsp bee pollen

How to make a manuka honey & blueberry smoothie


Place all the ingredients except the bee pollen in a blender and blitz until smooth.


Divide between two glasses and top each with a teaspoon of bee pollen. Serve immediately.


  • 50g spinach
  • 1 kiwi (peeled)
  • 1 banana (peeled and chopped)
  • 400ml apple juice

How to make a spinach & kiwi smoothie


In a blender, combine the spinach, chopped kiwi and banana and fill with the apple juice.


Blitz until smooth.


  • 1 aloe vera stem, with the green skin removed
  • 4 heaped tbsp blueberries
  • 4 heaped tbsp kale (equivalent to a big handful)
  • ½ a frozen banana
  • Squeeze of fresh lemon/lime juice

How to make an aloe vera, kale & blueberry skin smoothie


Blitz ingredients in a blender or food processor until the mixture is completely smooth. Add water until it’s a liquid consistency.


You could also add a few ice cubes to make the smoothie icy-cold and ready to drink or add a splash of coconut water before blending for extra sweetness.

The final say

Whether you’re looking for weight loss smoothies, you’re embarking on the smoothie diet yourself or you’re just looking for smoothie inspiration – we hope you found what you were looking for in our guide.

You also asked...

Is the smoothie diet good for us?


Are smoothies a good way to lose weight?


Can I drink 2 smoothies a day?

The advice in this article is for information only and should not replace medical care. Please check with your GP or healthcare professional before trying any supplements, treatments or remedies. Food supplements must not be used as a substitute for a varied and balanced diet and a healthy lifestyle.

Last updated: 1 November 2021



Author: Bhupesh PanchalSenior Regulatory Affairs Associate

Joined Holland & Barrett: Apr 2019

Masters Degree in Toxicology and BSc Hons in Medical Biochemistry

Bhupesh started his career as a Clinical Toxicologist for Public Health England, advising healthcare professionals all around the country on how to manage clinical cases of adverse exposure to supplements, pharmaceuticals, cosmetics, industrial chemicals and agricultural products.

After 7 years in this role and a further year working as a drug safety officer in the pharmaceutical industry, Bhupesh joined Holland & Barrett as a Senior Regulatory Affairs Associate in 2019.

Read more
  • Visa
  • MasterCard
  • PayPal
  • AmericanExpress
  • ApplePay
  • ClearPay
  • AliPay
  • Instagram
  • Pinterest
  • Facebook
  • Twitter
Copyright © Holland & Barrett Retail Limited, 2023. All rights reserved. hollandandbarrett.com is a trading name of Holland & Barrett Retail Limited,. Registered office: Samuel Ryder House, Barling Way, Nuneaton, Warwickshire CV10 7RH. Registered in England: company no. 2758955. Registered VAT no. 211727395.