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Fruit Smoothie Question

My son doesn’t like to eat fruit, but he makes fresh fruit smoothies every day with some plain yogurt added. Should I be worried about how much (natural) sugar he’s ingesting with berries, apples, OJ, pineapple? 

With the war against sugar ever-expanding, even fruit has found itself in the spotlight. Cyclists eat fruits like bananas, dried fruit, and it is common to drink a fruit smoothie after a long ride.

Fruit contains three types of sugar: fructose, glucose, and a combination of the two, called sucrose. Sucrose makes up table sugar. How does that relate to fruit, though? The main thing to remember is that sugar is sugar. Whether the sugar comes from fruit or a can, the body treats it the same. Sugar is a type of carbohydrate, and research has shown that excess sugar is linked to an increased risk of heart disease, obesity, fatty liver disease, and type 2 diabetes. A study published in JAMA Internal Medicine found that people who consumed 25 percent or more of their daily calories from sugar were nearly three times as likely to die of heart disease than those who took in less than 10 percent of their daily calories from added sugars.

It is useful to look at the nutritional profiles. A can of soda, for example, is 140 calories of sugar and nothing else. A banana has about 70 calories of sugar. But fruit isn’t just sugar – it also provides vitamins, minerals, and fiber, which helps digestion. So overall, the sugar from fruit is much better for you than a can of coke.

But the story does not end there. Fructose, the other type of sugar, deserves mention. Fructose is mainly found in fruit. It is also artificially produced and used in many processed foods. Fructose is much sweeter than glucose. For example, compare a piece of fruit to a potato. More importantly, fructose promotes energy storage for later use, than giving us energy, like glucose. Fructose shoots straight to the liver and is turned into fat for storage. This is one reason drinking fruit juice or even consuming too much fruit can lead to weight gain.

Is it better to eat or drink your fruit?

This is where the rubber meets the road. Drinking a fruit smoothie gives the body a sugar bolus, much like drinking a coke. Sure, smoothies have some fiber and vitamins, but they do not do much after being pulverized in a blender. Drinking fruit smoothies exposes us to big sugar spikes. These sugar spikes contain a lot of fructose and eventually leads to weight gain. This is the reason you should not drink your calories.

Drinking a fruit smoothie every day is probably not the healthful act it seems to be. When you are young and your metabolism is not broken, the effect of drinking sugar bombs does not readily show itself. But do this for several years, and your body will start to show signs of metabolic damage, weight gain, and fatigue. This happens from exposing the body to high sugar loads every day, multiple times a day. Eventually, our cells become resistant to sugar and produce fat. Think of loading a suitcase. Once it is overloaded, the suitcase cannot close and hold its contents properly. Cells overloaded with sugar can only hold so much, and the excess sugar spills over into the blood and goes to the liver, where it is turned into fat. When you start gaining weight, this is late in the game.

A short word about dried fruit: dried fruit is loaded with fructose and has preservatives, which are probably not good for you. Eat a half a bag of dried pineapple, and, along with risking GI trouble, you’ll also take in 800 calories and 168 grams of sugar—and that’s a lot of extra calories. Agave is pure fructose and used in a lot of yogurts and drinks.

If you are going to eat fruit, it is better to eat it whole and in moderation. That’s not to say you should avoid dried fruit entirely, though. Carrying a few pieces on your long rides can help keep your sugar levels up and avoid bonking.


For more information about fructose and sugar, read the book – The Sugar Fix: The High-Fructose Fallout That Is Making You Fat and Sick by Richard Johnson MD