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“Eating three portions of wholegrain foods such as porridge every day protects your heart by slashing blood pressure levels,” reported the Daily Express. It said this could be as effective as taking medication.

The study behind this story demonstrates that wholegrain foods give a slight reduction in blood pressure in middle-aged individuals without cardiovascular disease. The study did not assess the effect of porridge itself on health, but compared a diet containing both wholewheat food and oats with a diet high in wholegrain wheat and a diet high in refined grains.

This was a well-conducted randomised controlled trial. Overall, the results support health advice that a diet containing recommended amounts of wholegrains can have a positive effect on blood pressure, which is an important marker of cardiovascular health. This positive effect on blood pressure can be expected to translate into benefits in terms of risk of coronary artery disease and strokes, although this study did not measure such health outcomes.

Where did the story come from?

The study was carried out by researchers from the University of Aberdeen. Funding was provided by the Food Standards Agency and the Scottish Government. Any oat cakes used in the study were provided by Paterson Arran Ltd. The study was published in The American Journal of Clinical Nutrition.

What kind of research was this?

This research assessed how three daily servings of wholegrain foods (either wheat or a mixture of wheat and oats) affected certain markers of cardiovascular disease risk in relatively high-risk individuals.

Evidence has built up over time that eating a diet high in wholegrain foods is associated with a reduced risk of chronic diseases such as diabetes, high blood pressure and coronary artery disease. The evidence is mainly from cohort studies, with one large meta-analysis of cohort studies concluding that three servings of wholegrains a day may protect the heart.

The researchers noted that evidence from a large intervention study was needed, which is why they carried out this randomised controlled trial.

What did the research involve?

Men and women aged between 40 and 65 years from Aberdeen volunteered to take part between September 2005 and December 2008. The participants’ BMIs ranged from 18.5 to 35 (from healthy weight to obese). Of these, the researchers included only people who were either sedentary or moderately active, and who had signs of metabolic syndrome or moderately high blood cholesterol. Those with diagnosed cardiovascular disease, diabetes, high blood pressure or thyroid conditions were excluded. People who habitually ate a lot of wholegrain fibres or took supplements were also excluded. This process resulted in 233 participants for the study.

The participants were randomly allocated to one of three treatment groups for 12 weeks: refined diet, wheat, or oats plus wheat. Apart from these dietary restrictions, the participants were allowed to eat normally. Before they began taking the treatment foods, they were asked to eat only refined cereals and food containing cereals that had been refined and white bread for four weeks) so that everyone was eating the same initially.

The main difference between the three groups was the type of refined cereals and bread being eaten. Those in the refined food group ate only refined cereals and white bread. The wheat group ate only wholemeal bread and wholegrain cereals, while those in the oat and wheat group had a mix of wholewheat foods and oats. Each group ate three servings of the treatment food a day. In total, the recommended servings for the day equalled the amount recommended by the Food Standards Agency for levels of nonstarch polysaccharides (18g/day). The researchers report that the participants were provided with refined, wheat- or oat-based whole grain foods that are widely available in UK shops. They do not specify further which types. Aside from the food that the researchers supplied, the volunteers were able to select their own foods to eat and advice on what to substitute was tailored to individual participant’s diets.

Several measurements, including weight, health, level of exercise, use of medications and anthropometric measures such as blood pressure, arterial stiffness and blood lipids were taken four times during the trial (before the run-in period, and at the start, end and during the trial). The participants kept seven-day food diaries before the study started as well as during the trial. At the end, the authors assessed whether there was an association between the experimental diet and the markers of health that they had measured.

What were the basic results?

In total, 206 participants completed the study and were available for analyses. As expected, at the end of the study, those in the wheat and the wheat plus oats groups were eating more nonstarch polysaccharides. Intakes of vitamin B6 and vitamin D were lower in the wheat plus oats group compared with the refined group, while zinc and magnesium were greater in both wholegrain groups.

After six weeks of their assigned diet, people in the wheat plus oats group had significantly reduced systolic blood pressure compared with the refined group (a reduction of 5mmHg versus 1.3mmHg) and by 12 weeks this improvement was seen in both wholegrain groups. Diastolic blood pressure did not change. There was also significantly reduced pulse pressure in both wholegrain groups (pulse pressure is the numerical difference between systolic and diastolic readings so if systolic readings are going down we would expect pulse pressure to go down too). There were no changes in blood fats except that in the refined food group, ‘bad’ cholesterol (LDL cholesterol) reduced significantly as did total cholesterol. There was no apparent effect of the diet on other markers of cardiovascular health including C-reactive protein, interleukin-6 and markers of insulin problems, including glucose levels.

How did the researchers interpret the results?

The authors conclude that daily consumption of three portions of wholegrain fibre significantly reduces systolic blood pressure and pulse pressure in middle-aged, healthy, overweight men and women. They note that the observed reduction “was similar to” that seen in drug trials and that such levels could reduce the incidence of coronary heart disease and stroke by more than 15% and 25%, respectively.

Conclusion

This was a well-conducted randomised controlled trial, the results of which appear to show that eating wholegrains influences certain markers of cardiovascular health. The findings raise several issues:

The researchers say this study is the first of its kind to demonstrate a positive effect of wholegrains on blood pressure. They discuss a similar study, the WHOLEheart study, which found beneficial effects in terms of blood lipids and insulin, but which did not find any effect of wholegrains on blood pressure. The researchers discuss the possible reasons for this, suggesting that their study is more robust when it comes to measuring the effects of wholegrain on blood pressure.

The study measured only indirect outcomes (proxy outcomes) of cardiovascular health. This means that while the researchers claim that the reductions they have seen here equate to the level of effect that would reduce the risk of stroke and cardiovascular disease, this study cannot prove that wholegrains would have such an effect.

The effect on blood pressure was only on systolic blood pressure, not diastolic. Blood pressure is a measure of the force of your blood in the blood vessels as the heart beats. A blood pressure reading constitutes two measurements: systolic when the heart pumps and the pressure is at its highest and diastolic when the heart relaxes and the pressure is lowest. Both are recorded during a single heartbeat. When interpreting blood pressure both systolic and diastolic levels need to be taken into consideration together, as both are indicators of cardiovascular health. This study noted a small (about 4-5mmHg) improvement in systolic blood pressure with wheat, but the medical benefits of this are difficult to generalise and they are likely to depend on a person’s blood pressure at the start. People in this study did not have high blood pressure. Generally, above 140mmHg systolic and above 90mmHg diastolic is considered to be high. The average systolic blood pressure of participants in this study was around 130mmHg.

While on its own the study cannot prove that wholegrains reduce the risk of stroke and cardiovascular disease, overall, the findings support existing evidence that wholegrains in the diet are important for cardiovascular health. They are recommended as part of a healthy, balanced diet and along with recommended levels of physical activity may help to prevent cardiovascular disease. The study did not compare the effects of whole grains with drugs for blood pressure lowering so any claims that this change to diet achieves the same as drugs do is premature.

 

Don't bother forcing whole wheat pasta down your throat; white pasta is just as good for you, says Jennie Brand-Miller, one of the world's foremost authorities on the glycemic index.

White bread is, indeed, as wicked as everyone thinks it is -- but so are a lot of whole-grain breads and brown rice, said Brand-Miller, in Vancouver recently to promote the fourth edition of her book, The Low GI Handbook: Guide to the Long-term Health Benefits of Low GI Eating, and for meetings with a research client looking to market an edible-fibre product.

The glycemic index is a tool for measuring the impact of food carbohydrates on blood sugar.

Foods with a high-glycemic-index rating (70 and above) are digested quickly and cause blood-sugar levels to soar and ultimately crash, while low-glycemic-index (GI) foods (55 and below) are digested more slowly and produce small blood sugar fluctuations.

Eating low-GI foods has many health benefits including greater satiation -- good news for people looking to lose weight.

But knowing which foods have a low-GI rating is not always easy.

"A common misconception is that low-GI foods are always high in fibre, that they are the 'brown' version of foods, as in brown pasta or brown rice," said Brand-Miller, a University of Sydney human-nutrition professor who has specialized in GI and carbohydrate research for almost 30 years.

"Fibre content is not a guide to the glycemic index of a food," she said. "There are a lot of whole-grain breads that have a high GI. The simple reason is they've been cooked and processed, the particles are small, the starch is fully hydrated during processing and [digestive] enzymes can attack quite quickly. The only way you tell the GI of a food is to actually test it."

Brand-Miller's lab conducts rigorous tests to determine the glycemic rating of individual foods.

"There is nothing crude about the GI. It's probably the most precise measure we have in nutrition," she said.

"Most potatoes are high GI, most white rices, most breads whether brown or white will be high GI but, on the other hand, I can say most pasta will be low GI, as will most legumes such as lentils and chick peas. Even canned lentils and canned chick peas are still low GI," she said.

Strangely enough, Uncle Ben's brown rice has a low GI.

"They make a lot of their rices in a sachet. Two-minute rices. They've had to do a whole lot of research to come up with varieties of rice that don't go all soggy and sticky,' Brand-Miller said. "They've actually chosen varieties where the starch stays quite hard."

Be suspicious of anything that melts in your mouth.

"If you want a really quick, on-the-spot guide to the glycemic index, just hold the food in your mouth and see if it disappears quickly," she said.

"Compare a piece of white bread and white pasta. If you eat white bread, half the carbohydrates will be digested or dissolved before you swallow it, but the shape of that pasta will still be evident in your mouth after two minutes. It's not the pasta itself that makes you fat."

As for whole wheat pasta, it has a glycemic index of 40 compared to white pasta's 45.

"It's not really worth the trouble," Brand-Miller said.

Meanwhile, white bread has a glycemic index of 70, while some puffed, salty, low-fat snack foods come in at an astronomical 90.

"You may as well be eating pure glucose," she said.

"Blood-sugar levels or, more correctly, our blood-glucose levels, are linked to just about every disease process," she said.

"Whether it's diabetes or cardiovascular disease or cancer, or weight gain with time, blood glucose has something critical to do with it."

Brand-Miller said solid evidence shows a low-glycemic-index diet helps prevent Type 2 diabetes. It also appears to protect against cardiovascular disease.

"In North America, your lifetime risk of getting diabetes is one in three. A low-glycemic-index diet can reduce that risk by about 50 per cent -- or from 33-in-100 people, to 16."

As for heart disease, "the wrong sort of carbohydrate calories [such as those found in bread] are producing just as much harm as saturated fat calories," she said.

"We actually haven't moved forward in terms of dietary management of heart disease in the last 25 years," Brand-Miller said.

"People are still dying of heart disease which is related closely to what they eat. We might be helping people to survive a heart attack, but we're not actually reducing the rate of heart attack.

"The problem is these [refined] carbohydrate calories that have replaced saturated fat have been shown over and over again to have increased cardiovascular disease because, when your glucose levels get very high, you create oxidative stress and that is what causes inflammation -- and inflammation of the lining of the blood vessels is what creates the thickening of the blood vessels. That means blood vessels are less responsive and the heart has to work harder."

Australia has a not-for-profit glycemic-index symbol program run by the diabetes organization in that country. Foods with a low GI rating are permitted to make that claim and use the low GI symbol.

"I would really like to see that symbol become international," Brand-Miller said. "Juvenile diabetes organizations around the world could adopt it."

In general, most modern, starchy foods have a high-glycemic rating, while most fruit and vegetables, with the exception of potatoes, have a low rating. But it isn't as simple as that. Foods with more fat tend to have lower GI ratings, as do foods that contain acids.

 

At her Melbourne home, there won't be 19 different kinds of cookies. The tree won't be trimmed this year. And the peanut butter and chocolate fudge will have to wait.

Dashing her family's hopes of freedom before Christmas, an investigator with the Florida Parole Commission set a tentative release date of March 17 for longtime fugitive Paula Carroll.

The 56-year-old grandmother recently was sentenced to another year in prison for escaping from her Ocala cell in 1975 and eluding authorities for more than 34 years. That further delayed her parole release on the original charge: concealing stolen property.

"I was hoping that one of the spirits of Christmas would come visit me," said her husband, 65-year-old Ray Brown, who knew the fugitive as Sharon Brown. "I feel like Scrooge. It's not going to be a holiday without her."

The St. Patrick's Day release date was devised to allow time for the commission to again hear her case.

Commission members already are aware of Carroll's years of dedication to her community as a Boy Scout leader and school volunteer. Her defense attorney, however, said they must go through the typical approval process, which entails two hearings in Tallahassee, before she's freed.

"It's the same bureaucratic nonsense where they have the meetings and the voting," said John Eagen, her Tallahassee lawyer. "That's the reason the date was set 90 days from now."

But during those hearings, which likely will last no more than a few minutes, the commission will have the option to adjust the date. That leaves open the possibility that Carroll could be freed earlier.

"I really started getting a good feeling when the parole commission said they knew what a good person she really is and that she deserves to be out helping people," Brown said. "Now, I just don't know what to do."

In a jailhouse interview with FLORIDA TODAY last month, Carroll said she would look at the bright side of delayed freedom: There would be much less holiday cooking to do and no need to catch up on the shopping she typically does throughout the year leading up to Christmas.

"She's OK with it," Eagen said. "She's taking it in stride because she knows it's going to end."

Brown recalled past years when his family would watch the Melbourne Christmas parade, and his wife would make cookies and hot chocolate for the young attendees. During today's parade, however, Brown will visit his wife at Lowell Correctional Institution in Ocala.

"My Christmas will start when I see her walk through the door," he said, "and I see the sparkle in her eye, and I see her smile."