Too Much Fruit?
Many popular commentators suggest that we limit fruit intake to two pieces of fruit a day due to the fructose content. However, there is a big difference between consuming fructose in fruit and consuming fructose added to foods in products such as high-fructose corn syrup.
Dr. Bruce Bistrian, a professor at Harvard Medical School explains in a the role of fruit in a Harvard newsletter, Rethinking fructose in your diet. 1
The newsletter concludes with the following advice:
However, this recommendation is incorrect by 6 teaspoons of sugar a day for women and 9 teaspoons of sugar a day for men.
David Jenkins (the originator of the Glycemic Index) and colleagues compared three diets over a two week period.2
- high vegetable diet: leafy and low-calorie vegetables with an emphasis on leafy vegetables and pods, fruits, and nuts with 20 servings of fruit and 40 servings vegetables
- high starch diet: whole-grain cereals, legumes, low-fat dairy products, olives, and olive oil and 11 servings per day of fresh fruit and vegetables
- low saturated fat diet: low-fiber starchy foods, skim milk dairy products, olive, and safflower oils, together with 5 servings per day of fruit
The 20 servings of fruit on the high vegetable diet could easily contain more than 200g of fructose – equivalent to about 6 cans of cola.
There were no ill effects on any of the diets. The average body weight, total cholesterol and LDL cholesterol were reduced on all three diets with the greatest reduction in cholesterol occurring in the high-vegetable diet.