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Are fruits bad for you?

Can you eat too much fruit?

Or is fruit too full of sugar and destined to hurt you in the long run?

In other words, is that famous apple a day REALLY going to keep the doctor away?

Today we’re going to talk about fruit and clarify some of the misunderstandings which swirl around these beautiful gifts of nature.

What Exactly Is Fructose?

To talk about fruit is to talk about fructose.

Fructose is a natural sugar found in fruits, vegetables and even honey. However, fructose can also be created artificially as a sweetener made of processed corn for example. You can find fructose sweeteners in different forms: crystalline (which is 100% fructose), table sugar (with 50% fructose and 50% glucose) or high-fructose corn syrup (HFCS) with different proportions of fructose – e.g. HFCS-42 and HFCS-55, which correspond to the percentage of synthesized fructose present in the syrup. These industrial forms of fructose are what you can find in soft drinks, juices, processed foods and baked goods.

A lot of people talk about how fructose is bad for you and is one of the main factors that has plunged us into an epidemic of obesity. Furthermore, people have also jumped to the conclusion that if fructose is bad for you, then that must mean that fruit also is bad.

Nothing could be farther from the truth.

Fruit should not be a victim of the sugar wars. Let’s take a look why…

Is There a Difference Between the Fructose in Fruit and the Fructose in Table Sugar?

One of the first questions we must ask is “Should we treat all fructose the same?”

More specifically, does industrial fructose have the same effect on your body as the fructose that you ingest when you eat a piece of fruit?

The simple answer is NO.

One of the main differences between fructose in fruit and the fructose added to drinks or foods is their fiber content.

Fruit has a lot of fiber. Table sugar and related products have none.

So what exactly is it about fiber that makes the difference?

Table sugar and other fructose sweeteners don’t have fiber to slow digestion, and the ‘sugars’ hit the bloodstream immediately. Repeated spikes in blood sugar overwork the pancreas, setting the body up for insulin resistance and the health problems that come with it – like type 2 diabetes.

But because the fruit does have fiber, the fructose acts differently; in effect the fiber helps keep the cell walls intact and the sugar therefore remains inside the fruit’s cells.   It thus takes a much longer time for the digestive tract to break down the cells, the sugars enter the bloodstream slowly and the liver has more time to metabolize them.

There are also non-extractable polyphenols (NEPP) that are bound to fiber.  Some of the health benefits associated with the intake of dietary fiber may be due to the presence of these polyphenolic compounds. Moreover, polyphenols found in apples can decrease the absorption of sugars by the cells lining our intestines.

An additional benefit to fiber is that it prevents us from overeating. Fiber satiates; you feel full faster and longer.

In the end, fructose is not ‘bad’ from all sources. Fructose in fruit, combined with the fruit’s high phytonutrient and high fiber content, is assimilated completely different by the body than its manufactured table sugar.

But What About Fructose Toxicity?

Another argument critics make when it comes to fructose is that it is toxic.

Simply stated, fructose becomes toxic when the body isn’t able to process it. Toxicity can lead to metabolic disease, obesity and other health problems.

Dr. Robert Lustig, professor of pediatrics at the University of California, San Francisco argues that the threshold for fructose toxicity for adults is about 50 grams a day. Alarmingly, due to the huge intake of added sugars and table sugar, 50 grams a day is the average intake for most adults in the U.S. while adolescents consume a whopping 75 grams!

The medical community is clear about the fact that –once again–the fructose in whole fruits acts differently and does not lead to toxicity.

Researchers emphasize that consuming lots of fruits has never been linked with any negative health effects. In fact, repeated observational studies reveal that fruit consumption can actually lower body weight and therefore the risk of obesity-associated diseases.

An Apple a Day Really Does Keep the Doctor Away!

So back to our original question.

Is it really true –as the old saying goes—that an apple a day really does keep the doctor away?

The fact of the matter is that whole fruits with their fiber intact have a high satiety level and are full of nutrients your body really needs.

Like other fruits, apples are excellent for your health as they contain a boatload of antioxidant-rich health-promoting polyphenols.

So What’s the Bottom Line?

The truth about fructose is simple.

When it’s stripped from its source, processed and added to foods and drinks, it’s a recipe for metabolic disaster.

But when it’s packaged inside the perfect, whole fruit, it’s just plain good for you – in any amount.  

Science is PROVING the truth of the old adage: eat your apple to keep the doctor away.

Rosane Oliveira, DVM, PhD

President & CEO, Plant-Based Life Foundation | Dr. Rosane Oliveira combines a lifelong passion for nutrition with 25 years of genetics research to create programs that help people develop healthy habits on their journey towards a more plant-based lifestyle. She is a Visiting Clinical Professor in Public Health Sciences and was the founding director of the first Integrative Medicine program at the UC Davis School of Medicine. She completed her postgraduate studies in Brazil and did her postdoctoral training in immunogenetics and functional genomics at the University of Illinois at Urbana-Champaign.