Everybody loves fruits juice and many people think it’s a staple for their refrigerator. Orange juice is often served for breakfast for its Vitamin C nutrients. For that reason, some people prefer to drink orange juice over water. However, obesity expert, Dr. David Ludwig, says that even the 100 percent, all natural, no-sugar-added fruit juices are as bad as soda. “All of these beverages are largely the same. They are 100 percent sugar”, Dr. Ludwig added. (1)
What’s bad in fruit juice? Fructose – a monosaccharide, a simple sugar is not what you may think. It is known that Fructose doesn’t trigger insulin like glucose. So, the term “low-glycemic” is often used with high fructose products, like agave nectar. However, it doesn’t mean they are good for you. It may not put any glucose into the bloodstream; however, fructose does go directly to the liver to be metabolized.
Dr Robert Lustig, Professor of Pediatric Endocrinology at the University of California, San Francisco, explains how it reacts in the body. “…the only organ in your body that can take up fructose is your liver. Glucose, the standard sugar, can be taken up by every organ in the body, only 20% of glucose load ends up at your liver. So let’s take 120 calories of glucose, that’s two slices of white bread as an example, only 24 of those 120 calories will be metabolized by the liver, the rest of it will be metabolized by your muscles, by your brain, by your kidneys, by your heart etc. directly with no interference. Now let’s take 120 calories of orange juice, same 120 calories but now 60 of those calories are going to be fructose because fructose is half of sucrose and sucrose is what’s in orange juice. So it’s going to be all the fructose, that’s 60 calories plus 20% of the glucose, so that’s another 12 out of 60 – so in other words 72 out of the 120 calories will hit the liver, three times the substrate as when it was just glucose alone.” (2)
When it metabolizes in the liver, fructose elevates uric acid, which increases inflammation, and also causes high blood pressure. This reaction potentially damages your kidneys. Also fructose contributes to fatty liver deposits much in the same way alcohol does. A fatty liver is one of the major causes of insulin resistance, as the liver is the first tissue to become resistant. Moreover, fructose suppresses leptin (which would tell you if you were full) and does not suppress ghrelin (which makes you think you’re hungry). The end result: Fructose has you eat more. Not only causing hypertension, other researches show that fructose feeds cancer cells and contributes to symptoms of irritable bowel syndrome (IBS)
Marlene Merritt, DOM, Lac comments another fact on fructose, “Fructose is also seven times more likely than glucose to make AGE’s — Advanced Glycation Endproducts. They are named AGE’s for a reason — they cause you to age faster. You know how if you cook sugar long enough it caramelizes? That’s basically what happens in your body with glucose and fructose. When proteins in your body are caramelized like that (glycated), they are permanently damaged and can never recover. And AGE’s are implicated quite strongly in Alzheimer’s, cardiovascular disease, stroke, cataracts, nephropathy, heart attacks, atherosclerosis, arthritis, etc. The list is quite long. This is one of the main reasons diabetics have such health problems.” (3)
So, do we need to stop eating fruits? No, we still can eat fruit in whole form, not juice form. Whole fruits contain fiber which reduces some of the negative effects of fructose consumption. However, you can’t eat a lot of fruits either. Some experts suggest an intake below 25 grams per day is relatively safe. If you eat 3 medium sized apples, your fructose intake is more than 27 grams. Please take look at the Dr. Richard J. Johnson’s fructose chart below and use them as reference. Moderation, as always, is key.