• strawberries


• peaches


• cantaloupe

• bananas


• apples


• mangos

Dr. Sanjay Gupta: If you limit your sugar you decrease your chances of developing cancer?

Lewis Cantley, PhD: Absolutely.

Cantley, a Harvard professor and the head of the Beth Israel Deaconess Cancer Center, says when we eat or drink sugar, it causes a sudden spike in the hormone insulin, which can serve as a catalyst to fuel certain types of cancers.

Lewis Cantley: What we're beginning to learn is that insulin can cause adverse effects in the various tissues. And of particular concern is cancer.

Why? Nearly a third of some common cancers -- including breast and colon cancers -- have something called insulin receptors on their surface. Insulin binds to these receptors and signals the tumor to start consuming glucose [which allows it to grow].

Lewis Cantley: Every cell in our body needs glucose to survive. But the trouble is, these cancer cells also use it to grow. So if you happen to have the tumor that has insulin receptors on it then it will get stimulated to take up the glucose that's in the bloodstream rather than go into fat or muscle, the glucose goes into the tumor. And the tumor uses it to grow.

Lewis Cantley's research team is working on developing drugs that will cut off the glucose supply to cancer cells and keep them from growing. But until there's a breakthrough, Cantley's advice? Don't eat sugar. And if you must, keep it to a minimum.

Cantley, a Harvard professor and the head of the Beth Israel Deaconess Cancer Center, says when we eat or drink sugar, it causes a sudden spike in the hormone insulin, which can serve as a catalyst to fuel certain types of cancers.

Lewis Cantley: What we're beginning to learn is that insulin can cause adverse effects in the various tissues. And of particular concern is cancer.

Why? Nearly a third of some common cancers -- including breast and colon cancers -- have something called insulin receptors on their surface. Insulin binds to these receptors and signals the tumor to start consuming glucose [which allows it to grow].

Lewis Cantley: Every cell in our body needs glucose to survive. But the trouble is, these cancer cells also use it to grow. So if you happen to have the tumor that has insulin receptors on it then it will get stimulated to take up the glucose that's in the bloodstream rather than go into fat or muscle, the glucose goes into the tumor. And the tumor uses it to grow.

"The chances are good that sugar is a bigger part of your daily diet than you may realize which is why our story tonight is so important," Dr. Sanjay Gupta noted on the television show '60 Minutes' on April 1, 2012.

"New research coming out of some of America's most respected institutions is starting to find that sugar, the way many people are eating it today, is a toxin and could be a driving force behind some of this country's leading killers, including heart disease."

Dr. Sanjay Gupta: What are all these various diseases that you say are linked to sugar?

Dr. Robert Lustig: Obesity, type II diabetes, hypertension, and heart disease itself.

Lustig says the American lifestyle is killing us.

Dr. Sanjay Gupta: And most of it you say is preventable?

Dr. Robert Lustig: Seventy-five percent of it is preventable.

Dr. Sanjay Gupta: Is it worse than just table sugar?

Dr. Robert Lustig: No. 'Cause it's the exact same. They are basically equivalent. The problem is they're both bad. They're both equally toxic.

Since the 1970s, sugar consumption has gone down nearly 40 percent, but high fructose corn syrup has more than made up the difference. Dr. Lustig says they are both toxic because they both contain fructose -- that's what makes them sweet and irresistible.

"First of all, people can't eat less, and people can't exercise more," Lustig continues.

Lustig says that he believes that there are biochemical forces driving people to overeat and under-exercise, and he believes that one of the major forces is excess insulin caused by excess fructose consumption.