That’s right. When you ingest sucrose, half of your intake is fructose. So, you can’t just avoid fructose by specifically looking for it on the ingredient list. Pretty much every sugar used in processed food will have fructose.
This is another important factor when comparing the different sugar levels in fruit. Since fruit is now the only source of sugar in my diet, I can’t JUST look for fructose content. I must also look for sucrose content and add half that value to the amount of fructose. Let’s now point out some differences in glucose and fructose, since that is what we are really comparing when we look at sucrose and fructose.
Both fructose and glucose are simple sugars, but that is about where there commonalities end. Glucose is used by EVERY cell in the body as well as by most organisms on earth. Why is it that the body (and almost all other organisms) use glucose over fructose? One theory is that because fructose is more likely to undergo glycation (form AGEs) it has more potential harm! AGEs build up and cause damage to the body over time, and can lead to heart disease, diabetes, and aging. If you haven’t read my many posts about AGEs, now would be a good time to start because they will only multiply. Ha. I am not finished with that topic yet, I’m just taking a tangential detour.
Glucose stimulates an insulin release, but fructose does not. So fructose is good for sugar, right? NO! Since fructose does net even begin to be digested by the body until it reaches the small intestine and thus does not have the blood sugar and subsequent insulin release that glucose causes, fructose has been marketed at a low GI healthy sugar. However, since fructose is much more likely to form AGEs, increase visceral fat, raise bad LDL, and cause hypertension, it is really the last thing anyone needs, health conscious or not.
What effect does fructose have on appetite in comparison to glucose? Since fructose does not cause an insulin release like glucose, when ingesting a meal with a high fructose content, less leptin (an endogenous hunger suppressant) will be released, likely leading to a higher food intake. Lower amounts of leptin has been correlated to a higher body fat percentage. Also, with a higher fructose intake, ghrelin (an endogenous hunger stimulant) levels rise. These changes in leptin and ghrelin were not observed with glucose. Considering the obesity epidemic the USA is facing, maybe a little more emphasis should be placed on lowering dietary sugar, especially high fructose corn syrup.
Since fructose leads to high triglycerides in the blood, which interfere with insulin signaling, high fructose consumption can also lead to insulin resistance problems; yet another reason people at risk for or already diagnoses with diabetes need to stay away from fructose. This also has an effect on brain functioning and plasticity!
Fructose acts as destructive poison in our bodies rather than a beneficial resource, but it is in almost all processed foods! In a whole foods diet, fructose (and total sugar) intake is dramatically reduced from that of a standard American unless a person is binging on dates or something. For most people, limiting fructose intake to that only of fruit is a positive big step, and I am by no means down playing that decision. However, for my own goals, I am taking this a step further and will only be eating high fructose fruits rarely. In my next post, I am going to do a fruit sugar content comparative for my most used fruits.
