Why some people need to eat apples in moderation. I love apples but this is really enlightening.

Some People May Need to Eat Apples in Moderation

The other variable we haven't yet covered is fructose, a type of sugar that is linked to many chronic health problems when consumed in excess. I believe most will benefit from restricting their fructose to 25 grams a day, and as little as 15 grams a day if you have insulin or leptin resistance.


This includes fructose from whole fruits like apples. Apples are a relatively high-fructose fruit, with 9.5 grams in a medium-sized apple. Apple juice will contain considerably more, which is another reason why you're better off eating apples in their whole form.
It is also important to time your eating of fructose-rich foods like apple correctly. One of the tricks that I personally use is to time my fruit intake. Eating one after a calorie-rich meal for 'dessert' will not have the same effect as if you eat it after a glycogen-depleting workout.

In the former case, the apple's fructose is more likely to contribute to weight gain and insulin resistance; in the latter case, it will harmlessly replenish your glycogen stores within your muscles or be burned directly during your workout. I have actually been able to lose weight by increasing my fruit intake in this fashion. This works far better if you are metabolically adapted to burn fat as your primary fuel. 
If you're insulin or leptin resistant (are overweight, diabetic, hypertensive, or have high cholesterol), which includes about 80 percent of Americans, then it would be advisable for you to limit your fruit intake to about 15 grams per day, which would be equivalent  

to eating approximately one apple and a handful of blueberries -- unless you timed the fruit consumption as described above and were doing fairly significant exercise in which you were burning a few hundred calories.
If you are not insulin/leptin resistant, (are normal weight without diabetes, hypertension or high cholesterol) and regularly engage in strenuous physical activity or manual labor, then higher fructose intake is unlikely to cause any health problems. In this case, you can probably eat more fruit without giving it much thought.

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