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Your Brain On Carbs: Study Suggests How Sugary, Starchy Foods May Lead to Addiction

Published on July 3, 2013,

A new study published in The American Journal of Clinical Nutrition found that the brain responds differently to some types of carbohydrates than others — and some sugary foods trigger the same reward mechanisms as drug and alcohol addiction. This is from the New York Daily Post…

Milk Shake

In the study, researchers observed the brain activity of 12 overweight or obese men

between the ages of 18 and 35 in the hours after they consumed milkshake meals. The milkshakes were identical in taste as well as calories, nutrients and carbohydrates, but one set of shakes was made with high-glycemic carbs, such as the kind found in white bread, white rice and processed sweets, that spike blood sugar more quickly. The other set contained low-glycemic carbs such as those found in whole wheat bread and brown rice that cause a more gradual rise in blood sugar.

Predictably, when subjects drank the high-glycemic shakes, their blood sugar levels rose more quickly, and several hours later had dipped lower than when they drank the low-glycemic version. They also reported feeling hungrier.

But researchers also noticed substantially more activity in the parts of the brain that regulate reward and craving, the same areas activated in addicts, four hours after the men drank the high-glycemic shakes.

Lead study author Dr. David Ludwig, director of the obesity research center at Boston Children’s Hospital, said the brain activity may suggest why some people get stuck in a cycle of reaching for — and overeating — sugary, starchy foods.

“Beyond reward and craving, this part of the brain is also linked to substance abuse and dependence, which raises the question as to whether certain foods might be addictive,” Ludwig said in a statement.

“Limiting high-glycemic index carbohydrates like white bread and potatoes could help obese individuals reduce cravings and control the urge to overeat.”

Eating too many high-glycemic foods isn’t good for anyone, but the bigger picture of whether a person can become addicted to food — or to specific type of food like high-glycemic carbs — is more complicated, said Dr. Lisa Young, RD, PhD, adjunct professor of nutrition at New York University.

“I wouldn’t jump so fast to call it addiction, but it’s possible in a certain subset of people,” Young told the Daily News. “There are other factors you need to look at, at the same time. When some people eat a cookie they can’t stop, but other people can stop. You’re dealing with psychological behavior.”

More at:  Your brain on carbs: Study suggests how sugary, starchy foods may lead to addiction

Just one fizzy drink a day raises men’s risk of aggressive prostate cancer by 40%

Published on December 3, 2012,

Scientists from Lund University in Sweden have published a study in the American Journal of Clinical Nutrition suggesting that just one sugary soft drink a day could raise a man’s odds of developing prostate cancer. This is from the UK’s Daily Mail…

Soft drinks on shelves in a Woolworths superma...

Soft drinks on shelves in a supermarket (Photo credit: Wikipedia)

A 15-year study found those who drank 300ml of a fizzy drink a day – slightly less than a standard can – were 40 per cent more likely to develop the disease than those who never consumed the drinks.

Worryingly, the risk applied not to early-stage disease that was spotted via blood tests but to cancers that had progressed enough to cause symptoms.

This is significant as faster-growing forms of prostate cancer are more likely to be fatal.

It is thought that sugar triggers the release of the hormone insulin, which feeds tumours.

Prostate cancer is the most common type in British men, affecting almost 41,000 a year and killing more than 10,000.

The study, published in the respected American Journal of Clinical Nutrition, is far from the first to link the sugary soft drinks enjoyed by millions of Britons every day to poor health. Previous research has flagged up heart attacks, diabetes, weight gain, brittle bones, pancreatic cancer, muscle weakness and paralysis as potential risks.

The Swedish scientists behind the latest work said that while more research is needed before the link with prostate cancer can be confirmed, there are already ‘plenty of reasons’ to cut back on soft drinks.

For the study, they tracked the health of more than 8,000 men aged 45 to 73 for an average of 15 years. The men, who were in good health at the start of the study, were also quizzed about what they liked to eat and drink.

At the end of the study, they compared the dietary habits of the men who had been diagnosed with prostate cancer with those who remained healthy and found a clear link between sugary drinks and the disease.

Lund University researcher Isabel Drake said: ‘Among the men who drank a lot of soft drinks  we saw an increased risk of prostate cancer of around 40 per cent.’ The analysis also linked large amounts of rice and pasta, cakes and biscuits, and sugary breakfast cereals with a less serious form of the disease.

There was no link with fruit juice. Diet drinks, and tea and coffee with sugar, were not included in the study.

More at:  Just one fizzy drink a day raises men’s risk of aggressive prostate cancer by 40%

High-carb diet tied to possible breast cancer risk for some

Published on August 2, 2012,

Reuters has a report on a new study suggesting older women who eat a lot of starchy and sweet carbohydrates may be at increased risk of a less common but deadlier form of breast cancer.

The findings, from a study of nearly 335,000 European women, do not prove that your French fries, sweets and white bread contribute to breast cancer.

But they do hint at a potential factor in a little understood form of breast cancer, according to a researcher not involved in the work.

Specifically, the study found a connection between high “glycemic load” and breast cancers that lack receptors for the female sex hormone estrogen.

A high glycemic load essentially means a diet heavy in foods that cause a rapid spike in blood sugar. The usual culprits include processed foods made from white flour, potatoes and sweets. A sweet, juicy piece of fruit can also raise blood sugar quickly. But since fruits are low in calories, they don’t contribute as much to your diet’s glycemic load.

So-called estrogen receptor (ER)-negative tumors account for about one-quarter of breast cancers. They typically have a poorer prognosis than ER-positive cancers because they tend to grow faster and are not sensitive to hormone-based therapies.

In this study, postmenopausal women whose diets were very high in glycemic load had a 36-percent higher risk of ER-negative breast cancer, compared with women whose diets had the lightest load.

In general, a diet with a high glycemic load is not a particularly healthy one, noted Christina Clarke, a research scientist at the Cancer Prevention Institute of California in Fremont, and a consulting assistant professor at Stanford University.

“These types of diets have been associated with many negative health outcomes,” said Clarke, who was not involved in the study.

So although the current findings do not prove cause-and-effect, they can give women another reason to make healthier diet choices, according to Clarke.

Lead researcher Isabelle Romieu, of the International Agency for Research on Cancer in Lyon, France, did not respond to an email request for an interview.

From a scientific standpoint, Clarke said the results are interesting because so little is known about what causes ER-negative breast cancers. Most breast tumors – the ER-positive ones – have their growth fueled by estrogen.

“We really don’t know anything about what causes (ER-negative) tumors,” Clarke said. “This study gives us a really important clue for future research.”

Diets with a high glycemic load are associated with a bigger secretion of insulin, a hormone that regulates blood sugar. High insulin levels, in turn, have been linked to certain cancers, possibly because insulin helps tumors grow.

The current findings hint at a role for “insulin pathways” in ER-negative breast cancer, according to Clarke. “But there’s definitely more work that needs to be done,” she said.

The findings, which appear in the American Journal of Clinical Nutrition, are based on a long-running European study on nutrition factors and cancer risk.

Of nearly 335,000 women in the study, 11,576 developed breast cancer over a dozen years. Overall, there was no link between breast cancer risk and glycemic load – estimated from diet questionnaires the women completed at the study’s start.

But the picture changed when the researchers focused on postmenopausal women with ER-negative cancer. Among women in the top 20 percent for glycemic load, there were 158 cases of breast cancer, versus 111 cases in the bottom 20 percent.

When breast tumors also lacked receptors for the hormone progesterone, the gap was a bit more pronounced.

Still, the numbers “weren’t huge,” Clarke noted. And there are many other factors that could be different between those groups of women, although the study did account for some of them, including weight, exercise habits, calorie intake and smoking.

Clarke pointed out that there is no single factor in any woman’s risk of breast cancer. But, she said, the findings offer more incentive to eat a balanced diet that limits refined carbs in favor of healthier fare – like lean protein, vegetables, “good” fats and high-fiber grains.

“Really, you want to avoid these (high glycemic load) diets anyway,” Clarke said.

More at: High-carb diet tied to breast cancer risk for some

Original source: American Journal of Clinical Nutrition, online July 3, 2012.

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