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Why Smoothies Can Sabotage Your Healthy Eating Goals

Smoothies have always been related to weight loss and healthy eating, as they are often perceived as low calorie, full of nutrients and easy to grab and go. Is this really the full picture though?

Sure, smoothies contain fruit and sometimes vegetables. Protein powder can be added to help make them more filling. Additionally a whole host of 'superfoods' and supplements can be included to pack a nutritional punch to your favourite shake.

So what's not to love? They are portable, refreshing and contain tons of these healthy ingredients...right?

Of course some of those ingredients can definitely benefit your health, but smoothies as a whole can also play some tricks and can actually get in the way of your goals when compared to consuming whole foods. Let me explain:

1. Smoothies are often just fruit

It is very common for a smoothie or shake to contain a mixture of several pureed fruits and nothing more. Perhaps if you go to a fancier smoothie bar they may give the option of adding things like frozen yogurt, protein powder or greens for an additional cost, but if you go to your local juice bar, many of their famous smoothies are simply fruit based.

Why is this an issue?

While a great source of vitamins and minerals, fruit is also very high in simple carbohydrates, which digest quickly and raise our blood sugar fairly quickly as well. Furthermore, when you make a smoothie, you are consuming many more fruits than you normally would when eating them whole because you are pureeing them up. With this comes excess calories, a high spike in blood sugar and an end product that is not very filling.

2. They don't keep you full

There are a number of reasons why smoothies don't leave you feeling very satisfied.

a) As mentioned before, fruit is digested quickly and faster digestion means that the energy from that food is available more readily and can thus be used up quicker by the body. Through not having to work so hard to break the food down and using up that energy at a faster pace, your hunger will come back sooner than something that was a bit slower to digest.

b) There is often no fibre added. This removes another slow-digesting component that will increase fullness.

c) Lack of protein. This is the most filling of the macronutrients (carbohydrates, fats and protein)

d) Lack of satiating and slow digesting fats

e) They are pureed, or, in other words, digested for us already. So even if they have some more filling components to them (fibre, fat or protein), our body still doesn't have to do much work to digest them so we will be hungrier sooner.

f) Most don't perceive fluids to be as filling at whole foods (Read more here). Psychology comes into play here as these smoothies are seen as 'less food like' and often leave us wanting more sooner.

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Why is this an issue?

If they don't keep you full for long, your energy levels may be sent on a roller coaster as your blood sugar rises quickly when you drink it to suddenly fall just as fast as you digest and absorb it quickly. These steep climbs and falls can leave us irritable, tired, unable to concentrate and even give us headaches. On top of that, these quick dips in energy can leave us craving certain foods, often sweets, as we look to find another energy source.

If your goal is to lose weight, one of the biggest things you want to ensure is satiety or fullness. The more full you are from a given meal, the less likely you will be to overeat between meals or at the next meal of the day. If a smoothie packs in a large number of calories and doesn't keep you full for very long you may find yourself eating more calories than you regularly do or want to.

3. They may have hidden ingredients

If you are not making a smoothie at home yourself you may not know 100% what is going into your shake. Many commercial companies and stores will add more sugars, artificial sweeteners, and higher calorie products in order to make it more appealing to our tastebuds.

Why is this an issue?

Although it may be tasty, it may not serve to benefit us and our health goals, as there is a big difference between puree fruit and a milkshake. If your goal is to lose weight and your smoothie connoisseur places a full fat and overly sweetened bar of frozen yogurt into your shake without your knowing, he is not helping you keep within your calorie goals. What could be more problematic is if you have an allergy and one of their ingredients contains that allergen and you get sick.

4. They can make you bloated and gassy

Having a large volume of simple carbohydrates, such as fruit, can cause a degree of bloating as some of those sugars will find their way to the colon and begin fermenting. This processes can lead to extra gas and discomfort in some people. Furthermore, some of the add-on ingredients, such as milk based protein powders, greens formulas and sweeteners, may not be digested well for some and can lead to stomach upset.

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Why is this an issue?

If your goal is to feel energized and confident in your own skin, consuming something that will cause you to feel distended, uncomfortable and sluggish is not ideal.


Smoothies appear to have a 'health halo' around them that may not actually be a deserving title. Liquid calories are often not as filling as they should be and thus can leave us hungry and wanting more food despite us consuming a normal meal's worth (or more) of calories already. Even if your goal is does not include being overly mindful of calories, most don't like the feeling of quick energy bursts with equally quick energy crashes, so still smoothies appear not to be the best option.

What is found to be the best option is to consume whole foods in a balanced meal. This provides you with all of the nutrients you need in a good ratio so that you have long lasting energy, are satisfied and don't end up over consuming calories (if that is your goal).

Can there be a better smoothie option?

Now, it is understandable that people are busy and sometimes smoothies are just convenient and easy to be able to get in a quick meal on the go or in a rush. If a whole food meal is not an option, take these tips for making your smoothie as filling, balanced and satisfying as it can possibly be.

Tip 1: Add fruit, but watch the quantity. stick to 1/2 to 1 cup of fruit for a serving. Berries are great as they are high in fibre, antioxidants and provide a sweetness naturally.

Tip 2: Add a protein source. This will keep you fuller for longer and slow the digestion of the fruit down. Some options could be a whey or plant based protein powder, a full serving of greek yogurt, cottage cheese or silken tofu.

Tip 3: Add a fibre source. This also helps to slow digestion and keep you filler. Try chia seeds, hemp hearts, flax meal or even a greens powder if you have one.

Tip 4: Remember a healthy fat. These are satiating and slow digesting. Try adding 1 tbsp of natural peanut or almond butter, 2 tbsp of seeds, 1/4 of an avocado, 1/2 tbsp coconut oil

Tip 5: Avoid too many added simple carbohydrates/sugars. Sweeten to your tastes, but test it out first before you add too much honey, maple syrup or other sweeteners as you may do it out of habit and don't actually need the added sugars.

Tip 6: Avoid the juice base. These are high calorie and high in simple sugars that will just lead to a sugar rush and crash. Stick to things like milk, dairy-free beverages, teas, etc that will provide some nutrients and leave the carbohydrates to the added fruits.

*These are just general tips, if you follow a certain dietary lifestyle or have different needs/restrictions (gaining weight, athlete, allergies, etc) you may need to change the balance of your smoothie based on those.

Do you enjoy smoothies? What's you favourite blend?