The Type, Not Just the Amount, of Sugar Consumption Matters in Risk of Health Problems

 Long-term fructose consumption impairs vascular and liver function in rats

Newswise, February 15, 2017 —The type of sugar you eat—and not just calorie count—may determine your risk for chronic disease. A new study is the first of its kind to compare the effects of two types of sugar on metabolic and vascular function. 

The paper is published ahead of print in the American Journal of Physiology—Heart and Circulatory Physiology.

Female rats were given a liquid solution of either glucose (a form of sugar found naturally in the body after carbohydrates are broken down) or fructose (sugar found in fruit and fruit juices) in addition to their normal diet of solid food.

The rats received the sweetened solutions for eight weeks, roughly equivalent to a person eating large amounts of sugar for six years. The sugar-fed rats were compared with a control group that received plain drinking water in addition to their food supply.

Researchers found that although both sugar-fed groups consumed more calories than the control group, the total calorie intake of the glucose-fed rats was higher than the rats that were given fructose.

Another surprising observation was that “despite this difference, only the fructose group exhibited a significant increase in final body weight,” wrote the research team.

In addition to higher weight gain, the fructose group showed more markers of vascular disease and liver damage than the glucose group.

These included high triglycerides, increased liver weight, decreased fat burning in the liver (a factor that can contribute to fatty liver) and impaired relaxation of the aorta, which can affect blood pressure.

These findings suggest that an increase in the amount of calories consumed due to sweeteners is not the only factor involved in long-term health risks.

The type of sugar may also play a role in increasing risk factors for heart disease, diabetes and other chronic diseases.

Read the full article, “Type of Supplemented Simple Sugar, Not Merely Calorie Intake, Determines Adverse Effects on Metabolism and Aortic Function in Female Rats,” published ahead of print in the American Journal of Physiology—Heart and Circulatory Physiology.

Foods Rich in Resistant Starch May Benefit Health

Newswise, February 13, 2017 — A new comprehensive review examines the potential health benefits of resistant starch, a form of starch that is not digested in the small intestine and is therefore considered a type of dietary fibre.

Some forms of resistant starch occur naturally in foods such as bananas, potatoes, grains, and legumes, and some are produced or modified commercially and incorporated into food products.

There has been increasing research interest in resistant starch, with a large number of human studies published over the last 10 years looking at a variety of different health outcomes such as postprandial glycaemia, satiety, and gut health.

The review summarises reported effects and explores the potential mechanisms of action that underpin them.

For example, there is consistent evidence that consumption of resistant starch can aid blood sugar control. It has also been suggested that resistant starch can support gut health and enhance satiety via increased production of short chain fatty acids.

“We know that adequate fibre intake—at least 30 g per day—is important for achieving a healthy, balanced diet, which reduces the risk of developing a range of chronic diseases. Resistant starch is a type of dietary fibre that increases the production of short chain fatty acids in the gut, and there have been numerous human studies reporting its impact on different health outcomes,” said Dr. Stacey Lockyer, co-author of the Nutrition Bulletin review.

“Whilst findings support positive effects on some markers, further research is needed in most areas to establish whether consuming resistant starch can confer significant benefits that are relevant to the general population; however this is definitely an exciting area of nutritional research for the future.”

Mediterranean Diet May Have Lasting Effects on Brain Health

Newswise, February 13, 2017 — MINNEAPOLIS – A new study shows that older people who followed a Mediterranean diet retained more brain volume over a three-year period than those who did not follow the diet as closely.

The study is published in the January 4, 2017, online issue of Neurology®, the medical journal of the American Academy of Neurology. But contrary to earlier studies, eating more fish and less meat was not related to changes in the brain.

The Mediterranean diet includes large amounts of fruits, vegetables, olive oil, beans and cereal grains such as wheat and rice, moderate amounts of fish, dairy and wine, and limited red meat and poultry. 

“As we age, the brain shrinks and we lose brain cells which can affect learning and memory,” said study author Michelle Luciano, PhD, of the University of Edinburgh in Scotland.

“This study adds to the body of evidence that suggests the Mediterranean diet has a positive impact on brain health.”

Researchers gathered information on the eating habits of 967 Scottish people around age 70 who did not have dementia. Of those people, 562 had an MRI brain scan around age 73 to measure overall brain volume, gray matter volume and thickness of the cortex, which is the outer layer of the brain.

From that group, 401 people then returned for a second MRI at age 76. These measurements were compared to how closely participants followed the Mediterranean diet.

The participants varied in how closely their dietary habits followed the Mediterranean diet principles. People who didn’t follow as closely to the Mediterranean diet were more likely to have a higher loss of total brain volume over the three years than people who followed the diet more closely.

The difference in diet explained 0.5 percent of the variation in total brain volume, an effect that was half the size of that due to normal aging.

The results were the same when researchers adjusted for other factors that could affect brain volume, such as age, education and having diabetes or high blood pressure.

There was no relationship between grey matter volume or cortical thickness and the Mediterranean diet.

The researchers also found that fish and meat consumption were not related to brain changes, which is contrary to earlier studies.

“It’s possible that other components of the Mediterranean diet are responsible for this relationship, or that it’s due to all of the components in combination,” Luciano said.

Luciano noted that earlier studies looked at brain measurements at one point in time, whereas the current study followed people over time.

“In our study, eating habits were measured before brain volume was, which suggests that the diet may be able to provide long-term protection to the brain,” said Luciano. “Still, larger studies are needed to confirm these results.”

The study was supported by Age UK, the UK Biotechnology and Biological Sciences Research Council, the UK Medical Research Council and the Scottish Funding Council SINAPSE Collaboration.

To learn more about brain health, visit www.aan.com/patients.

The American Academy of Neurology is the world’s largest association of neurologists and neuroscience professionals, with 30,000 members. The AAN is dedicated to promoting the highest quality patient-centered neurologic care.

A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, stroke, migraine, multiple sclerosis, concussion, Parkinson’s disease and epilepsy.

For more information about the American Academy of Neurology, visit http://www.aan.com or find us on Facebook, Twitter, Google+, LinkedIn and YouTube.