Smoothies and Weight Loss – What’s the Deal?

  • Written by Kelly Harris
  • September 12, 2021
  • 6 min read
smoothies and weight loss

We are all susceptible to a bit of weight gain every now and then. Nutritionists are no exception to this rule. I, for one, had a bit of a shock on the scales the other day at the doctor’s office. How could one ten-day quarantine period have done so much damage to my waistline?

After your 20’s and 30’s, weight loss can become increasingly difficult, as I have unfortunately found, but your tummy and taste buds will be pleased to know that smoothies can be a delicious and filling part of a healthy and sustainable weight loss strategy.

weight loss

Smoothies are a very versatile form of food to suit a wide variety of dietary needs. As they are essentially just blended fruits and vegetables, they can be very easy to digest. It’s equally as easy to make a smoothie with a high caloric density for people who need to gain weight/consume extra calories (such as athletes) as it is to make a smoothie with a low caloric density – for people who wish to lose weight.

I am not a big fan of calorie counting, but it can be helpful from time to time, just to remind you of how much you should be eating in a day. It only takes an extra 100 or 200 calories a day to end up gradually packing on the pounds and before you know it, you can’t button your jeans anymore. If you have a history of eating disorders, you should skip the calorie counting advice and use an alternative method to sense check your food intake, such as the NHS Eat Well Guide.  But otherwise, I find that a couple of weeks of logging calories on a food and fitness tracking app like My Fitness Pal or Cronometer really helps to get my portions back on track. I eat an extremely healthy diet, but my downfall is that my portions can get out of control if I’m not careful.


Weight Loss-friendly Smoothie Ideas

The secret to making a weight loss-friendly smoothie is to get the right balance of:

Low-calorie density fruits and vegetables, to bulk out your smoothie with sweet flavour and filling fibre
High-quality protein, to boost metabolism and regulate appetite
Just enough fat to keep you fuller for longer and help you absorb your fat-soluble vitamins

weight loss smoothies


1) Fruits and Vegetables

There are plenty of fruits and vegetables you can use to bulk out your smoothie. This is not the time for adding delicious medjool dates or fresh coconut chunks to your smoothie. By all means, include those in your diet, but keeping higher calorie elements out of your smoothie will mean you can enjoy them as a treat or a snack later in the day when you’ll really appreciate their delicious flavour and nourishing energy.

frozen blueberries

Personally, I like a smoothie that is still a bit dessert-like, so I tend to rely on blueberries and strawberries to bulk out my smoothies. They are sweet tasting and full of flavour but still low in sugars and rich in fibre with plenty of anti-inflammatory antioxidants. In the autumn, I’ll often make delicious low-calorie pumpkin spiced smoothies using canned pumpkin which I freeze in ice cube trays (an excellent source of fibre) blended with a bit of frozen sweet potato or half a frozen banana and some cinnamon. For my age, weight, body frame and activity level, I try to keep the fruit and vegetable portion of my breakfast smoothie to around 100 calories but you should adjust this to whatever is appropriate for your body’s needs. For example, 100 calories will get you:

– 1 small-medium banana
– 300 grams of frozen strawberries
– 200 grams of frozen blueberries
– 300 grams of canned pumpkin
– 15 cups of chopped spinach (but please don’t eat that much at once!)
– 3 whole cucumbers
– 2 heads of lettuce
– 3 carrots
– 120 grams of sweet potato
– 250 grams of butternut squash

So mix and match all of these delicious fruits and veggies until you find a flavour combo that works for you.


2) Protein

For the protein part of your smoothie, choose a high-quality protein source. I personally opt for a stevia-sweetened plant-based vanilla protein powder because vanilla enhances the natural sweetness of the fruit and I happen to think it’s delicious! But there are plenty of other protein sources you can use. Just make sure they haven’t added any sugar or artificial sweeteners (which can also sabotage your weight loss). As an example, I try to keep the protein content of my smoothie limited to around 80-100 calories. Here are a few protein-rich food ideas below of what you can have for 100 calories (although be aware they will vary in protein content):

– 25 grams of pure whey protein
– 25 grams of no sugar added peanut butter powder
– 100 grams of firm raw tofu
– ½ a can of cannellini beans
– ½ a cup of butter beans
– 70 grams of black beans
– 70 grams of chickpeas
– ¾ cup of frozen peas

protein powders


3) Fat

I know this is a weight loss smoothie, but if you don’t have a little fat with your breakfast, you are going to be hungry in an hour and when that croissant at the Pret A Manger counter starts winking at you, you’ll need the fortitude to spurn its advances. This is the part of your smoothie where a little bit goes a long way. As I like to keep my smoothie around the 300 calorie mark, I include around 60-70 calories worth of fat-rich foods in it. As I mentioned before, you might need to scale this up to suit your body’s needs and your own activity levels. Here are some examples of 70 calories worth of fat-rich foods.

– 10 grams of unsweetened natural peanut butter
– 10 grams of almond butter
– 40 grams of avocado flesh
– 2 tsp MCT (Medium Chain Triglyceride) oil

peanut butter shot


4) Liquid

Finally, you’ll need to add some liquid to your smoothie and here it is really up to you. I happen to love using the liquid part of my smoothie to sneak in some extra protein and nutrients. Be aware that some liquids can be high in sugars and calories so make sure that if you’re using a plant milk, that it is an unsweetened variety. I tend to use around 300 ml of liquid in my smoothie, and around 200 ml of that will be an unsweetened almond milk, cashew milk, pea milk or tiger nut milk. The rest is water.

almond milk shot

If you’re strapped for time, you can always order some Soil Association certified organic weight-loss-friendly smoothies from right here at The Honestly Good Smoothie Company which arrive frozen at your door, ready to pop into the blender. I’d recommend these ones if you’re wanting to keep to a lower calorie count:

The Hearty Healthy One

The Whirling Dervish

The Choc Banana Sundae

The Mexican One

The Almond Tart One


The Glowing One

The Vitamin Sea One

Wake Me Up

The Smoothie Spice

The Waldorf Cool

Berry Nice

The Grass is Greener

We hope you enjoyed this blog post. You may also like 15 Tips to Lose Your Lockdown Pounds.



Written by
Kelly Harris
Nutritional Therapist
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