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How sugar impacts the brain and body

For years, nutritionists have been pushing Americans to eat more vegetables and fewer desserts. But emerging research is increasingly showing the damage eating too much sugar can do to our health. This week on WRVO's health and wellness show "Take Care," hosts Lorraine Rapp and Linda Lowen speak with James DiNicolantonio, a cardiovascular research scientist at St. Luke’s Mid America Heart Institute in Kansas City and a leading authority on the effects of sugar on the body.

Lorraine Rapp: So what is it about sugar that makes it so harmful?

James DiNicolantonio: Well the reward from sugar is actually faster than drugs of abuse. You might be asking ‘how can sugar reward the brain quicker than IV use of drugs or inhaling certain drugs of abuse?’ And that’s because the brain is directly innervated with our taste preceptors so it’s an immediate intense reward surpassing that of drugs of abuse. It’s actually an evolutionary advantage why the substance is causing such a reward and that’s because fructose, which is an added sugar as I’m talking about table sugar, also known as sucrose or high fructose corn syrup, it helps us store fat. So, if we got a better reward from it, we would seek it out, we’d eat it more and we are able to get through periods of food scarcity. The only way we would seek it out and consume it is if we got a massive reward from it. But, unfortunately, we stripped out all the fiber and the phytonutrients from whole foods and we refined it to a pure white crystal, just like we refined cocaine into a pure white crystal. And so, it’s this pure form that’s so unnatural that it provides a tremendous reward and it overrides our self-control mechanisms and we can’t stop ingesting it.

Rapp: Which type of sugars are the worst offenders?

DiNicolantonio: So the two added sugars that are much more detrimental than even other types of carbohydrates -- there’s fructose, which is contained in high fructose corn syrup, and also table sugar, also known as sucrose. Those two added sugars are the really harmful ones because they’re bringing on fructose plus glucose and it’s the fructose part that’s extremely detrimental in the fact that it’s mostly metabolized by the liver. That leads to different metabolic harms than glucose, because every cell in the body can utilize glucose. So, the overall sugar load is dissipated by all the cells that are taking it up and it’s also regulated. So, only a certain amount can enter the cell, it’s being controlled by insulin. Not the case with fructose. Fructose is like a freight train and it’s coming into the liver almost 80 percent of the entire load and it’s unregulated. You get this tremendous hit on the liver and it’s causing oxidated stress and inflammation. And so it’s leading to all these chronic health problems and no one’s really talking about treating sugar addiction as our best approach to treat not only obesity but Type 2 diabetes.

Rapp:What are some suggestions for our listeners if we want to satisfy a sweet tooth but we don’t want to damage our health.

DiNicolantonio: Well, if you want to satisfy your sweet tooth, you first need to be satiated. I always go for an apple, or dark chocolate with some almonds to provide a little protein for some satiation. You can eat things that have sugar in it, but a whole food is the best way you want to get that sweet tooth fix.

Linda Lowen: Are you saying then that if you consume sugar you really never reach a level of satiety? You’ll still want more and more?

DiNicolantonio: In fact, it drives hunger. Fructose being metabolized differently than glucose in the body, actually stimulates hunger. And in the long run it promotes something called leptin resistance. And leptin is the signal from your fat cells to your brain telling your brain you have enough fat stores and you can stop eating. It blunts that signal. So now you’re always hungry. We used to blame people for overeating as they don’t have any self-control. In fact their biochemistry is out of whack because of the sugars they’ve been eating. It’s not their fault. And of course when you’re always hungry and you feel like you’re starved, you don’t want to exercise, your body is saying, wait a second, you don’t have enough food to exercise. So the overeating and underexercise – it’s a consequence of over-consuming added sugar. 

More of this interview can be heard on "Take Care," WRVO's health and wellness show Sunday at 6:30 p.m. Support for this story comes from the Health Foundation for Western and Central New York.