Are smoothies really healthy?
For most of our history as a species, humans evolved with a very high intake of plants in the diet. Yet most people today do not eat a whole lot of fruits and vegetables. Very few Americans even meet the relatively meager federal recommendations.
This is a bummer, because there are a whole lot of uniquely good things in edible plants. Maybe the most interesting thing about plants are their phytochemicals, like carotenoids and polyphenols. These compounds have a wide range of astounding health-promoting effects when we eat them, including:
- Fighting cancer
- Keeping arteries healthy
- Scavenging free radicals
- Stopping inflammation
- Controlling blood sugar levels
- Feeding good gut bacteria
- Blocking pathogenic microbes
- Protecting against cognitive decline
One easy and convenient way to get more fruits and veggies in your diet is to blend them, like into a tasty soup or smoothie.
But some people have questioned whether that is such a great idea. When you blend food, is it possible that you’re also disrupting some of the nutrients that make them good for you? It’s a reasonable question, especially for those of us who eat smoothies every day.
It’s not what you eat, it’s what you absorb
Let’s take a closer look at plant chemicals like beta carotene (the orange pigment in carrots and sweet potatoes) or lycopene (the red pigment in tomatoes and watermelon). These compounds are floating around inside the cell walls of fruits and vegetables.
In order for these nutrients to be accessed by our bodies, the walls need to be broken. Our teeth do a pretty good job at this. However, blenders do a much better job than any amount of chewing could ever possibly achieve. When you process plant matter into itty bitty particles, these beneficial plant compounds are not lost. In fact, they become several times more accessible to the body. As an example, lycopene is 2–3 times more bioavailable from tomato paste than it is from fresh tomatoes.
Another interesting aspect of this is fiber. Our ancient ancestors took in between 70–120g of fiber per day. Currently on average, Americans only get between 13–17 grams a day.
When you blend veggies into a smoothie, the fiber is left intact, which is awesome because fiber is really good for us. But even better, keeping the fiber intact also means that you may be getting more healthy polyphenols — which are often bound to fiber. This is likely part of the reason why a study found that apple smoothies provide way more polyphenols than apple juice. This is also why smoothies are usually a better bet for health than drinking juice.
So what’s the verdict?
The blender can break things down way better than our teeth (no matter how good of a chewer you are). This means that you may be able to access and absorb components of food more efficiently. Pretty cool.
But…great absorption is not automatically a good thing. Coca Cola is also absorbed rapidly, but it does our body no favors!
So you want to use quality ingredients. Use mostly whole fruits and veggies. If you’re looking for vitamins, minerals, fiber, and phytonutrients, greens are your best bet, and berries are pretty awesome too. Add in some frozen bananas and you’ve got a creamy delicious smoothie packed full of nutrients.
Overall, the science suggests that food processing isn’t automatically a bad thing. Ancient hunter-gatherers obviously did not have Vitamixes, but it is possible that intelligently devised smoothies could help us get closer to ancestral eating patterns. It could help ensure that we get more fruits and vegetables in our diet, while living in an era where that seems more challenging to pull off.
