Eating fruit is not so healthy?

Question

I've noticed many articles claiming that fructose is worse for person's health than glucose, leading to various health problems in the long run.

For example, this article suggests that:

While much of the research into this question is obscure, a growing body of research suggests that greater than 50 grams of fructose a day is detrimental and may start to cause Metabolic Syndrome and all the consequent problems.

However, some suggest that 25 grams should be the limit, and for people with known Metabolic Syndrome or it’s risk factors, 15 grams of fructose a day.

There is also a table below which shows the amount of fructose in common fruits:

• Lemons, 1 medium, 0.6 grams of fructose
• Strawberries, 1 cup, 3.8 grams of fructose
• Banana, 1 medium, 7.1 grams of fructose
• Apple, 1 medium, 9.5 grams of fructose
• Figs, dried, 1 cup, 23.0 grams of fructose

Ok, don't eat dried fruits, I get it, but I was surprised by how high in the list an ordinary apple is. I always had an impression apples are among the healthiest fruits, with lots of fiber and (what I believed) not so much sugar!

Now it turns out that eating, say, 2 apples and 1 banana adds up to ~26 grams of fructose, and actually breaks the (slightly more conservative) "healthy" threshold of 25 grams a day?

Answer 1

First, a couple of facts:

• Fructose is not only in fruits, but also in table sugar (sucrose), which is glucose + fructose, and thus in many sweetened foods.

• Various fruits contain fructose, glucose and sucrose in various proportions. Fruits high in fructose are apples, pears, mangoes, grapes, agave, watermelon and others (check on Nutrientsreview.com)

Conclusions of some studies:

1. Fructose and metabolic syndrome: Metabolic Effects of Fructose and the Worldwide Increase in Obesity (Physiological Reviews, 2010)

...fructose intake >50 g/day...was associated with increased postprandial triglyceride excursions...

There is, however, no unequivocal evidence that fructose intake at moderate doses is directly related with adverse metabolic effects.

So, >50 g/day of fructose can raise triglycerides, but this alone is not already metabolic syndrome.

2. Fructose and obesity. A critical examination of the evidence relating high fructose corn syrup and weight gain. (PubMed, 2007)

Based on the currently available evidence, the expert panel concluded that HFCS does not appear to contribute to overweight and obesity any differently than do other energy sources

I posted only 2 studies, which represent what I believe: Fructose does not contribute to metabolic syndrome and obesity (significantly) more than glucose or other energy sources (proteins, fats).