Mouse Study Hints at How Mediterranean Diet Protects the Heart

By Kathleen Doheny
HealthDay ReporterLatest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity Crisis Has Scaled Even the HimalayasObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

MONDAY, May 19, 2014 (HealthDay News) -- Study after study has shown that a Mediterranean-style diet rich in fish, nuts, vegetables and fruits seems to lower your risk of heart trouble.

Now, a new mouse study hints at why.

"When unsaturated fatty acids, found in olive, nuts and fish oils, are eaten together with a source of nitrate or nitrite, found in vegetables such as beetroot and those with green leaves, they form nitro fatty acids in the body," explained lead researcher Philip Eaton, a professor of cardiovascular biochemistry at Kings College London. Those fatty acids then lower blood pressure by inhibiting a particular enzyme.

The study is published online May 19 in the Proceedings of the National Academy of Sciences.

While the finding was made in animals and such results often can't be duplicated in humans, Eaton thinks it would also happen in people because they have the same enzyme.

Eaton noted that although the finding is new, there is evidence that drugs that inhibit the enzyme might lower blood pressure and some pharmaceutical companies are working on developing such medications.

For the study, the researchers' aim was to find out if inhibiting the enzyme was enough to lower blood pressure in the animals studied. They first created mice with a mutation that made the enzyme resistant to the effects of nitro fatty acids.

When they gave the mice an enzyme inhibitor, blood pressure decreased in wild mice but not in the mice with the resistant version of the enzyme. The inhibitor protected the wild mice from heart damage in a mouse model of high blood pressure, but did not protect the re-engineered mice. When they fed the mice the food in the Mediterranean diet that combine to make nitro fatty acids, the enzyme was again inhibited in the wild mice, but not the re-engineered mice.

"This study provides insights on the mechanics behind how eating vegetables aids in the reduction of risk of

Study Disputes Notion That Breakfast Is Key to Weight Control

Latest Diet & Weight Management NewsIs Breakfast the Key to Weight Control?Health Tip: If You Aren't Hungry, Don't EatDiabetes Drug Spurs Weight Loss in NondiabeticsObesity Crisis Has Scaled Even the HimalayasObesity, Overweight Rates Jump Worldwide, ReportWant More News? Sign Up for MedicineNet Newsletters!

THURSDAY, June 5, 2014 (HealthDay News) -- New research refutes the common belief that skipping breakfast could contribute to obesity.

Instead, researchers at the University of Alabama at Birmingham (UAB) found that passing on the first meal of the day doesn't help or hinder efforts to lose weight.

"The field of obesity and weight loss is full of commonly held beliefs that have not been subjected to rigorous testing; we have now found that one such belief does not seem to hold up when tested," senior investigator David Allison, director of the UAB Nutrition Obesity Research Center, said in a university news release. "This should be a wake-up call for all of us to always ask for evidence about the recommendations we hear so widely offered."

The study involved 309 overweight and obese adults between the ages of 20 and 65. The otherwise healthy participants were randomly told to eat breakfast or skip the meal. The study also included a control group that was given healthy nutrition information, but not any specific instructions about breakfast. People in this control group included those who ate breakfast and those who skipped breakfast.

The researchers analyzed the effects of eating or skipping breakfast on weight loss. They also examined how changing breakfast habits could influence efforts to shed unwanted pounds.

"Previous studies have mostly demonstrated correlation, but not necessarily causation," study author Emily Dhurandhar, an assistant professor in UAB's department of health behavior, said in the news release. "In contrast, we used a large, randomized, controlled trial to examine whether or not breakfast recommendations have a causative effect on weight loss, with weight change as our primary outcome."

The study, published online June 4 in the American Journal of Clinical Nutrition, revealed there was no difference in weight loss among the various groups.

"We should try to understand why eating or skipping breakfast did not influence weight loss, despite evidence that breakfast may influence appetite and metabolism," Dhurandhar noted.

Also, the findings only included body weight and did not examine the effects of breakfast habits on people's appetite, body fat and metabolism, she said.

"In addition, our study was 16 weeks in duration, which is longer than many previous studies; but it is not clear whether an effect of the recommendation would be clearer from an even longer duration study," Dhurandhar added. "Finally, we gave subjects a recommendation of what a healthy breakfast is, but left their choices of breakfast foods up to their discretion."

-- Mary Elizabeth Dallas