What makes a healthy smoothie?

Frozen Berry Smoothie

A dietitian’s guide to making a healthy smoothie.

By Simone Austin Advanced Sports Dietitian

Who doesn’t like the look of a pretty pink berry smoothie or the thought of the goodness in a green one? Smoothies are very popular and it’s no surprise, given how you can add your fruit and vegetables in along with other ingredients to make them so delicious, but how about nutritious too? What makes a smoothie healthy? How can you make a healthy smoothie, let’s take a look?

Sugar in a smoothie

My smoothie has fruit and maybe even some vegetables in it so it must be healthy right? Wrong. A smoothie sure can be healthy but it can also be a trap packed with more than a day’s recommended intake of sugar and a meal or more worth of kilojoules packed into one glass.

When you add your food into the blender to create your glass of goodness, it becomes liquid or semi liquid, chopping up the cells and breaking the food down, it basically speeds up the digestion process for you. It is easier now for the body to digest the food or drink and release the nutrients into the blood stream. One of these nutrients is sugar. Think of fruit, possibly oats or other cereal, these contain carbohydrate which when digested is broken down to smaller sugar molecules such as glucose and  fructose that we absorb. This doesn’t include sugar that also comes from honey or other syrups you might add and even dairy such as yoghurt and milk add the sugar lactose. It is about finding the balance and adding ingredients that will also provide other valuable nutrients in addition to the carbohydrate and sugar.

By comparison, when you eat fruit whole, the body needs to break down the skin and flesh before it can access the sugar inside. This has the benefit of the sugar entering the blood stream more slowly, aiding the body to keep its blood glucose level within the desired range. Research has shown it also helps with keeping us full for longer, as the food takes time to be digested and absorbed. Conversely, when you add a lot of fruit to a smoothie, it means your body is receiving an immediate and large sugar hit. You can help reduce this issue by moderating the quantity of fruit used and adding some ingredients to slow the digestion.

Key steps to make your healthy smoothie

Having the spread of macronutrients, protein, carbohydrate and healthy fats are key criteria for making a healthy smoothie. Meeting your individual nutrition needs is also important as what is healthy for you might not be what suits someone else. Here are the components to consider.

1. Portion

Place all the ingredients you plan to add to the smoothie on a plate. Take a look, is this more than you would eat in one sitting? If yes, then it is more than you need to add to the smoothie, unless you are trying to pack the energy into a smaller volume by blending to help you gain weight, take on more energy in one hit.

2. Protein

Add in a serve of protein as this is often forgotten in a smoothie and is a crucial part of every meal and snack. Protein will help slow the digestion of the whole smoothie, lowering the glycaemic index (GI- how quickly the sugar is released into the blood stream). Spaced out over the day protein will help with maintaining and repairing your muscle mass.

The protein part of the smoothie will often be part of the liquid which is best to add at the beginning for the benefit of the longevity of your blender blades (versus adding in solid rock frozen fruit first)! It could be cow’s milk, Rokeby Farms Probiotic Filmjolk, plant milks (choose those higher in protein- read labels) or yoghurt.

To boost protein further 100% nut butter, nuts, seeds and even oats add protein.

3. Fruit

Use a fist-size portion of fruit – you wouldn’t eat a whole banana, ½ a punnet of berries, ½ apple plus the other ingredients you may add to the smoothie all in one sitting, so the same goes when drinking them.

Keep the skin on fruit or better still blend the whole fruit where possible, for extra nutrients.

4. Vegetables

Add in vegetables, which are lower in sugar and packed with nutrients. Cucumber, and green leafy vegetables such as spinach, silverbeet and kale, are all great options. As these are bitter start small and grow! You still want to enjoy the taste of the smoothie.

5. Wholegrain

Don’t be afraid of carbs. Yes we want to manage the sugar load of the smoothie but we also want to vary the nutrients and boost the fibre. Wholegrains such as oats, barley or buckwheat you could try. These slower-release carbohydrates will increase the vitamin, mineral and phytonutrient content and provide dietary fibre. Research shows including regular wholegrains in your diet can reduce the risk of chronic disease and they are particular important for our gut health and regularity. By blending them in the smoothie it does make the carbohydrate more easy to digest, like that from the fruit, and release the sugar more quickly however the fibre and nutrient benefit is still there. If you have just been or are about to exercise the benefit of the carbohydrate release more quickly can be of benefit for fuel.

6. Healthy Fats

We need fat, of the healthy kind. They not only add flavor and texture they help absorb fat soluble nutrients, vitamins A, D, E and K. They come with the benefit of monounsaturated and polyunsaturated fats (including omega 3) for our heart and brain health. Consider avocado, nuts, seeds, yoghurt or milk and even a dash of extra virgin olive oil can make the smoothie creamy and boost the nutritional value.

7. Herbs and spices

Anything goes it seems these days. Herbs or spices are packed with antioxidants and although we have them in small amounts it all adds up over time plus they come with great flavour. Try cinnamon, fresh grated turmeric, parsley, basil, cumin seeds, nutmeg or fennel seeds.

There may be times when your body benefits from sugar and more of it quickly, such as during a long stint of exercise or for recovery after, when your muscle glycogen stores are getting low and you need to replenish them ready to go again. In this case you may want to up the quantity of fruit suggested to more than a fist size or upsize altogether. What ever your energy needs these smoothie making tips will help you make the perfect smoothie snack or meal!

All there is left to do now is blend, pour and drink!

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