MUSC News Center
Make this simple New Year's resolution for a healthier you
By Dawn Brazell | MUSC News Center | January 8, 2014
Consider learning about AGE before chomping down on that next bit of bacon or other fried food.
Here’s an easy New Year’s resolution to create a healthier you.
Add the word AGE or advanced glycation end product to your vocabulary. It’s one you’ll be hearing about more this year, especially if David P. Turner, Ph.D., has anything to do with it.
The hard part, though, is what to do when you know what it is. For Turner, who is an assistant professor in the Department of Pathology and Laboratory Medicine at the Medical University of South Carolina (MUSC), it meant giving up bacon. However, before anyone panics, there are other changes he recommends that can have a significant impact on creating a healthier diet.
His recommendations stem from what he’s learned in doing cancer health disparities studies in ethnic minorities.
One of those studies was presented last month at the sixth American Association for Cancer Research in Cancer Health Disparities conference. It is known that African-American men are 1.5 times more likely to develop prostate cancer and more than twice as likely to die from the disease compared with non-Hispanic white men.
“We found that AGE levels were highest in African-American men with prostate cancer,” said Turner, “Because obesity, poor eating habits, and an inactive lifestyle all promote AGE accumulation, and these factors are often more evident in African-Americans, we hypothesize that there is a link between these factors that could help explain why African-American men are more likely to develop prostate cancer and die from the disease.”
Turner and colleagues examined circulating AGE levels as well as those within tumors in African American and non-Hispanic white men with prostate cancer. They found that AGE levels were higher in serum from cancer patients compared with individuals without cancer. When analyzing AGE levels in prostate tumor samples, levels were highest in tumor samples from African-American patients.
It’s an important finding that warrants future research, and adds to existing evidence that Turner and colleagues want to educate the community about AGEs and how to reduce the effects.
“As our bodies use the sugars that we consume for energy they generate waste products, or metabolites, including molecules called advanced glycation end products, or AGEs,” Turner said, explaining there’s no way to completely eliminate AGEs. “AGEs naturally accumulate in our tissue as we grow older, and they have been implicated in diseases associated with aging such as diabetes, heart disease, and Alzheimer’s disease. They can also cause increased inflammation and the generation of potentially harmful chemicals known as reaction oxygen species, which both promote cancer.”
A common source of the AGEs that accumulate in the body comes from foods that are eaten and how they are prepared, which has significant implications for cancer health disparity and overall health, he said. “AGE content in the Western Diet has consistently increased over the last 50 years due to increased consumption of sugar-laden and cheap, processed, manufactured foods which are high in reactive AGE metabolites and can promote obesity.”
So what are sample AGE levels?
Studies have shown that one hundred grams of carrots have an AGE kilounit of 10. Raw chicken has an AGE level of 800, compared to poached chicken at 1,000 and fried chicken at 8,000. Bacon, fried for five minutes with no oil, racks up a tally of 91,577 AGE kilounits/100g.
Turner said he has people beg him during educational community talks he presents not to reveal what’s in a Big Mac or other popular fast food fare. “They don’t want me to ruin it for them. It’s the usual suspects – the high sugar, the high fat – the red meats,” he said of foods that score high. “Where it stands out, though, is the way we cook our foods that has the real impact on the AGE we find in the food.”
One hundred grams of a steak, for instance, has around 800 kilounits of these AGEs. “You fry it and it actually goes up to 8,000 because frying drives the reaction and further AGE formation.”
Research is being done on the effect of exercise on AGEs. It is thought to slow down the accumulation of these products and may actually reduce them slightly, he said. Diet is where the most impact can be made, though.
“These AGE products are involved with diseases of old age, diabetes, Alzheimer’s, stroke, cancer and cardiovascular problems. We want to get out the message that if you can cut down your child’s AGE content in three or four meals a week, over a lifetime, that’s a lot of AGEs you can reduce down, and you may be a lot less likely to get the diseases associated with old age.”
Their recent study focused on African-Americans within South Carolina. Research shows that more than 50 percent of African-Americans live below the poverty line and exercise very little. “We know that low poverty drives the use of low cost processed foods, which are unhealthy and are generally higher in AGEs. We saw these AGE accumulation levels were higher in African-Americans than they are in European-Americans. It was our hypothesis that we would see a difference, but the extent of the difference was a surprise. It’s significantly higher in African Americans.”
Turner wants to confirm his results in another study using a larger group that also examines the impact of poverty. Higher socio-economic groups tend to eat healthier foods. “It could be a low-income factor as much as it is a race issue when it comes to these glycation products."
Another promising area of research is the role of exercise in counteracting AGE accumulation. Turner is involved with a feasibility study with breast cancer survivors who will participate in a cardiac rehabilitation program for 12 weeks. Researchers will take blood samples and analyze AGE markers as well as other markers of breast cancer.
“We’re going to see if they’re indicative of recurrence in these breast cancer patients. In cardiac rehab you can get all this with insurance, but there’s nothing like this for cancer patients. This might turn into a landmark study if we can show this in the feasibility study and then in a larger grant. Maybe in the long-term, we can get some type of exercise intervention for all cancer patients, as well.”
Turner also will be studying if AGE levels can be biomarkers – powerful diagnostic tools – for physicians in treating cancer. For example, with prostate cancer, around 75 percent of patients won’t develop an aggressive type. However, 25 percent will need treatment. “We need biomarkers that will indicate the level of treatment needed so we can say your glycation products are low so that probably indicates your cancer isn’t aggressive. We’d need a lot of further studies to be able to say that though.”
In the meantime, Turner and colleagues are focusing on what they do know, such as the AGE-RAGE signaling pathway that can promote cancer. RAGE, or the receptor for advanced glycation end products, can get switched on by AGE metabolites in the body, he said.
“When RAGE is switched on, it alters what genes are actually expressed so we produce these proteins. These proteins that are activated increase the inflammation within our bodies. This is what is involved in the diseases associated with growing older. It also increases stress responses. If you have a more inflammatory cancer, it tends to be more aggressive. So when AGE activates RAGE, it increases all these inflammatory proteins in our bodies and may promote cancer.”
Turner, who provides community outreach with Hollings Cancer Center’s Cancer Disparities Program, loves leaving his lab to translate this information into practical terms for the lay public. “The take-home message is that these advanced glycation end products or reactive metabolites seem to be elevated in cancer. They seem to be particularly elevated in African-American prostate cancer patients. This might be across all cancers, but at the moment, we have mainly looked at prostate.”
Because of the community outreach, Turner has been getting regular requests for dietary information, which he sees as a good sign. It means the message is getting out.
“I might be a basic scientist, but I like working with cancer disparities groups. The more this gets out there, the better. It’s actually a lot of fun. It reminds me why I’m in the lab.”
(This study, a partnership with MUSC and S.C. State University, was funded in part by the National Institutes of Health as part of the South Carolina Cancer Disparities Research Center. Turner declares no conflicts of interest.)