About eight years ago I would have considered a smoothie a healthy snack or breakfast. It didn’t really matter what type of smoothie, at that point I lumped them all together in the “health” category. I know I’m not the only one because smoothie bars are popping up everywhere and patients are often reporting smoothies as part of their regular diet.
From working out to eating breakfast on the run, you probably have been encouraged to have smoothies as part of your daily routine. It is an easy way to increase your protein intake, which is necessary for muscle growth. What could be easier? Add protein powder to some blended fruit, yogurt, and/or fruit juice. After some investigation I now know this could be a huge problem and here’s why:
- Smoothies are a reservoir of hidden sugar
Unless your smoothie is 75 percent or more vegetables, it is mostly hidden sugar coming from fruit. We all know fruit is a source of natural sugar. Think about how many servings of fruit get added to a smoothie…two…three…four? Would you eat this many fruits whole in one sitting? Of course not! It is way too much sugar. In fact, a Nutrition Facts label from Booster Juice, listed sugar at 56 grams per single serving and total carbohydrates at 68 grams. Wow!
- Smoothies have more sugar than protein
Smoothies are always advertised as high in protein. The problem is that even though they may be high in protein, they are usually higher in sugar. Let’s check out a couple of examples to illustrate.
The first example is the Spinach Smoothie, again from the popular franchise Booster Juice. You many think you are getting a protein/spinach smoothie but when you check out the amount of protein it is only 3g!
Another popular pre-made smoothie comes from Body Systems Nutrition and is made with frozen yogurt:
| Calories | 350 | Sodium | 0 mg |
| Total Fat | 5 g | Potassium | 0 mg |
| Saturated | 0 g | Total Carbs | 50 g |
| Polyunsaturated | 0 g | Dietary Fiber | 0 g |
| Monounsaturated | 0 g | Sugars | 0 g |
| Trans | 0 g | Protein | 25 g |
| Cholesterol | 0 mg | ||
| Vitamin A | 0% | Calcium | 0% |
| Vitamin C | 0% | Iron | 0% |
You may think, “Well this one is great, look at all the protein!” Sure protein is listed at 25 grams and sugar is listed at 0 grams. We need to dig a little deeper though. This is how labels can trick you! You also have to look at the amount of total carbs listed and then subtract the fiber. This will give you a more accurate measurement of the hidden sugar. In this smoothie the amount of fiber is zero and the carbs are 50g! This means you are consuming twice as much sugar as you are protein.
- Smoothies can make you gain weight
How is this possible? I’ll give you a hint…it has to do with sugar. Whenever you consume sugar or starch your body produces insulin. Insulin is your fat storage hormone. Let me say that again, insulin is your fat storage hormone. Whenever you secrete insulin your body will store those calories in your fat cells. The only exception to this is if you are running a marathon or you haven’t eaten in two days and how often does that happen?
Armed with this information I hope you can now make an informed decision about your smoothie choices.
Ingredients matter. Don’t be fooled into thinking all smoothies are healthy.
Dr. Michelle Durkin is a Naturopathic Doctor at the Quinte Naturopathic Centre and resident health expert for the Eat Real Food Academy.
if I used one banana, a couple of scoops of pain yoghurt and a splash of almond milk, is that a healthy smoothie? I had a friend say she added a bit of cocoa powder to make it chocolatey….
Hi Anne! Thanks for your great question. The answer is “it depends”. One medium banana will have about 27g of carbohydrate, aka sugar. Plain yogurt will have about 12g per cup and the splash of almond milk with cocoa powder would be negligible. So in the smoothie you describe you are getting about 40g of carbohydrate. IF your goal is to keep your insulin & inflammatory signals in check this might be a little too much for one meal. I usually encourage patients if they need fruit in a smoothie to use fruits like berries instead of a banana. They are more colourful than a banana therefore they have more nutrients per gram of carbohydrate. Also, as a comparison, 1 cup of strawberries provides 12g of carbohydrate versus 27g in the banana. Avocado can also be used to make your smoothie creamy for anyone who needs, or wants to avoid the yogurt (dairy intolerance people, that means you!)
Funny….bananas are now a treat. I used to have a smoothie most mornings using a banana and frozen blueberries and lots of spinach and some water and a protein powder. I really prefer to crunch my breakfast now….seems to keep me full longer. Frozen strawberries, an avocado, coco powder and a splash of vanilla blended are now a special dessert?
Isn’t it interesting that once you are away from sugar, fruit tastes so much sweeter? Last week I told my niece that the corn on the cob we were having was dessert. It didn’t even phase her 🙂
Hi Anne,I use a medium banana, 1.5cups of mixed berries, 3tbsp of hemp heart seeds, 1cup chopped kale and water. Is this healthy because I have been doing this every morning for about a week with the goal of losing some weight
Hi Ann,
Keep with the kale and hemp hearts – the banana and mixed berries are going to give you 49g of sugar. This will undermine your weight loss goals. As a start I would ditch the banana and add in some avocado instead.