The Sugar in Fruit: Is the sugar in fruit bad for you?
Fruit, regardless of the fact that it is a "natural" sugar, can still lead to a number of diseases. There is an epidemic right now in this country of insulin resistance and metabolic syndrome, which are associated with poor processing of sugar, increased blood sugar, and the conversion of sugar into fat. We know that this can lead to heart disease, strokes, dementia, cancer, and, of course, diabetes. Now, some have argued that the sugar in fruit is somehow processed differently than other types of sugar and while this might be true to an extent, the sugar in fruit might actually be worse. There are 3 types of sugar: fructose, glucose and sucrose. The main sugar in fruit is fructose, but there is some glucose as well as other sugars like sorbitol. Glucose also comes from complex carbohydrates that get converted into glucose and glucose is what supports our blood sugar. Sucrose is table sugar and is a combination of fructose and glucose.
Our cells metabolize each type of sugar differently. Fructose is metabolized in the liver and converted directly into triglycerides. The buildup of triglycerides can lead to fatty liver disease as well as an increase in "belly fat.” The other lesser known fact is that fructose gets converted into chemical compounds called purines, which then get converted into uric acid. Uric acid can cause gout and has been associated with heart disease. While gout has traditionally been thought to be due to the intake of rich foods like red meat, beer and shellfish, excess fruit consumption can actually lead to a gout attack.
When thinking about the risks and benefits of eating fruit, the other thing I like to consider is the anthropological perspective. Thousands of years ago, fruit was not available in the quantities it is today. There was a seasonal cycle to the fruit we had access to and we ate a lot during the times it was available. However, there were many months in a row when there was no fruit available. We probably ate fruit during the summer and fall to build up fat stores so that we could survive during the harsh winters. But do we need those excess fat stores now? In supermarkets across the country, we have access to almost any fruit we want year-round. What if our bodies are not designed to deal with this much sugar all the time? There is something to be said about eating seasonally and listening to our bodies as to what we need when we need it. To me, eating watermelon in January doesn't really make sense but eating watermelon in July does.
There are certainly benefits to eating fruit, namely the phytonutrients and antioxidants they contain. Eating fruit containing the highest level of nutrients but the lowest amount of fructose is ideal.