That being said, in vegetables and fruits, the fructose is mixed in with fiber, vitamins, minerals, enzymes, and beneficial phytonutrients, all of which help moderate the negative metabolic effects. If you are healthy, eating small amounts of whole fruits is fine and potentially beneficial.
However, if you suffer with any fructose-related health issues, such as insulin resistance, metabolic syndrome, heart disease, obesity, or cancer, you would be wise to limit your total fructose consumption to 15 grams of fructose per day. This includes fructose from ALL sources, including whole fruit.
If you are not insulin resistant, you may increase this to 25 grams of total fructose per day on average. Let me restate my recommendations on fruit and fructose consumption as simply as possible:
- If you're insulin or leptin resistant (are overweight, diabetic, hypertensive, or have high cholesterol), then it would be advisable for you to limit your fruit intake. As a general rule, I recommend limiting your fructose intake to a maximum of 15 grams of fructose per day from ALL sources, including whole fruit.
- 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.
- However, if you are in category two above, you might benefit from a further refinement. Fruit will still increase your blood sugar and many experts believe this will increase your protein glycosylation. So my approach is to consume the fruit typically after a workout as your body will use the sugar as fuel rather than raise your blood sugar.
- Additionally, if you're an endurance athlete, you can probably get away with eating fairly large amounts of fruits, since your body will use most of the glucose during exercise, so it won't be stored as fat.
- If you're still unsure of just how stringent you need to be, get your uric acid levels checked and use that as a guide. See below for details…
Measuring Your Uric Acid Level Can Help Determine How Much Fruit Is Right for You
The higher your uric acid, the more sensitive you are to the effects of fructose. The safest range of uric acid appears to be between 3 and 5.5 milligrams per deciliter (mg/dl), and there appears to be a steady relationship between uric acid levels and blood pressure and cardiovascular risk, even down to the range of 3 to 4 mg/dl.
According to Dr. Richard Johnson, the ideal uric acid level is probably around 4 mg/dl for men and 3.5 mg/dl for women. If you are one of those who believes fruit is healthy no matter how much you eat, I would strongly encourage you to have your uric acid level checked to find out how sensitive you are to fructose. Eat the amount of fruit you feel is right for you for a few weeks and then check your uric acid level and see if your levels are healthy.
If they are elevated, you might try reducing the fruit to recommended levels and rechecking your uric acid level. Many who are overweight likely have uric acid levels well above 5.5. Some may even be closer to 10 or above. Measuring your uric acid levels is a very practical way to determine just how strict you need to be when it comes to your fructose – and fruit -- consumption
Article written by Dr. Mercola.