As if we needed another reason not to consume high-sugar food and drink, a new study from UCLA shows that cancer cells actually prefer fructose to glucose when it comes to making new DNA. The study raises more concerns about high-fructose corn syrup (HFCS), the notoriously bad-for-you sweetener, which is a mix of fructose and glucose, and continues to get a bad rap as more research unfolds.

Cancer cells use sugar to proliferate, but till now it was unclear whether they "preferred" one type of sugar over another. To determine whether there were any differences in how cancer cells use glucose and fructose, Anthony Heaney and colleagues took pancreatic cancer cells from patients and placed the cells in petri dishes, surrounded by one of the two kinds of sugar. The researchers labeled the sugar molecules so that they could look at exactly what the cancer cells were doing with them.

The team found that the cells actually used fructose "preferentially" over glucose in a pathway that produces nucleic acids, which are the building blocks for DNA. This means that the cells were using fructose as fuel to multiply.

The results are especially noteworthy "given the significant dietary change that has occurred in human fructose consumption since the mid-20th century". In other words, Americans are consuming more fructose than ever, largely in the form of HFCS. According to the university news release, between the years 1970 and 1990, HFCS consumption rose by a whopping 1000% in this country.

There is particular concern that cancer patients may be taking in high levels of fructose in their regular diets, and that this could work against their treatment and recovery. The authors do suggest that down the road it may be possible to "inhibit fructose-mediated actions" in cancer cells (i.e., interfere with the pathways that use fructose), in order to stop their growth.

"The bottom line is the modern diet contains a lot of refined sugar including fructose, and it's a hidden danger implicated in a lot of modern diseases, such as obesity, diabetes and fatty liver," said Heaney. "This paper has a lot of public health implications. Hopefully, at the federal level, there will be some effort to step back on the amount of HFCS in our diets."

While we should certainly not quit eating fruit, which has much lower levels of fructose and many additional health benefits, it won't hurt to cut down on the sugary processed foods and drink, including soda. Your body will thank you.

The study was published in the July 20, 2010 online issue of Cancer Research.