Health Benefits of Fiber: Heart Disease

Fiber protects against cardiovascular disease -- especially in women

Foods high in fibre provide good protection against cardiovascular disease, and the effect is particularly marked in women. This is shown in a new study from Lund University in Sweden.

The study, which was recently published in the scientific journal PLOS One, involved the study of the eating habits of over 20 000 residents of the Swedish city of Malmö, with a focus on the risk of cardiovascular disease. The importance of 13 different nutrient variables (aspects of fibre, fats, proteins and carbohydrates) was analysed.

"Women who ate a diet high in fibre had an almost 25 per cent lower risk of suffering from cardiovascular disease compared with women who ate a low-fibre diet. In men the effect was less pronounced. However, the results confirmed that a high-fibre diet does at least protect men from stroke", says Peter Wallström, a researcher at Lund University and the primary author of the article.

The exact reason for the difference between the sexes is unclear. However, a probable explanation is that women consume fibre from healthier food sources than men do. Women ate a lot of fibre in the form of fruit and vegetables, whereas the most important source of fibre for men was bread.

"The difference in the results for men and women shows that we need to pay more attention to gender when we conduct research on diet", says Peter Wallström.

However, the researchers did not identify any definite links between the other nutrients in the study and cardiovascular disease, for example the proportion of saturated fat or sugar in the diet.

"These results should be interpreted with a certain amount of caution. Almost everyone eats more saturated fat than recommended, including the participants in many other population studies. It is therefore difficult to compare recommended and high fat intake. Other types of study that have been carried out have shown that those who limit their fat and sugar intake are at lower risk of cardiovascular disease", says Peter Wallström.

Peter Wallström is sceptical of 'extreme' diets and says that the dietary recommendations from the National Food Administration are good, despite having received criticism:

"The National Food Administration's dietary advice, which is based on extensive research, is well balanced. In the short term, most weight-loss diets achieve their aim as long as you follow them. However, we know too little about the long-term effects to be able to recommend more drastic changes to one's diet", says Peter Wallström.

Data for the study has been taken from the Malmö Diet and Cancer population study, which has involved 30 000 Malmö residents since the start of the 1990s. The participants have given blood samples and detailed information about their diet.

Fiber-Rich Foods May Cut Your Risk of Heart Disease

Boosting the amount of fiber in your diet may lower your risk for heart disease, a new study finds.

"With so much controversy causing many to avoid carbohydrates and grains, this trial reassures us of the importance of fiber in the prevention of cardiovascular disease," said one expert not connected to the study, Dr. Suzanne Steinbaum, a preventive cardiologist at Lenox Hill Hospital, in New York City.

In the study, researchers led by Diane Threapleton, of the School of Food Science and Nutrition at the University of Leeds, in England, analyzed data from the United States, Australia, Europe and Japan to assess different kinds of fiber intake.

Her team looked at total fiber; insoluble fiber (such as that found in whole grains, potato skins) soluble fiber (found in legumes, nuts, oats, barley); cereal; fruits and vegetables and other sources.

The study also looked at two categories of heart disease. One, "coronary heart disease" refers to plaque buildup in the heart's arteries that could lead to a heart attack, according to the American Heart Association. The second type of heart trouble is called "cardiovascular disease" -- an umbrella term for heart and blood vessel conditions that include heart attack, stroke, heart failure and other problems, the AHA explains.

The more total, insoluble, and fruit and vegetable fiber that people consumed, the lower their risk of both types of heart disease, the study found. Increased consumption of soluble fiber led to a greater reduction in cardiovascular disease risk than coronary heart disease risk. Meanwhile, cereal fiber reduced the risk of coronary heart disease more than the risk of cardiovascular disease, researchers found.

For every additional 7 grams per day of fiber consumed, there was a significantly lower risk of both types of disease, according to the study published online in BMJ.

Sports dietitian Dana Angelo White said the findings are in line with what nutritionists have long known about the importance of a high-fiber diet.

"The tricky part is finding ways to get Americans to eat more [fiber]," said White, who is also an assistant clinical professor at Quinnipiac University in Hamden, Conn. "The daily recommendation ranges from 20 to 38 grams per day. This may seem like a tall order for most folks, but can be achieved by making some small dietary changes."

The British study found that adding just 7 grams per day of fiber to the diet boosts heart health. According to White, people can get that amount of fiber from the following:

* 1 1/2 cups of cooked oatmeal (7 grams)

* 1 1/4 cups of shredded wheat cereal (8 grams)

* Two slices of whole-wheat bread (6 to 7 grams)

* One large pear (8 grams)

* 1 cup raspberries (8 grams)

* 1/2 cup black beans (7.5 grams)

The study authors said their findings support current recommendations for increased fiber intake and that the reduced heart disease risk associated with consuming more fiber could potentially benefit "many thousands" of people, according to a journal news release.

Steinbaum added that "it's critical that people understand that whole grains -- such as barley, bulgur, millet, quinoa, brown rice, rye, oats and whole wheat, along with fruits, vegetables, nuts and seeds -- are part of a heart-healthy diet."

Study strengthens link between low dietary fiber intake and increased cardiovascular risk

A new study published in the December, 2013 issue of The American Journal of Medicine shows a significant association between low dietary fiber intake and cardiometabolic risks including metabolic syndrome, cardiovascular inflammation, and obesity. Surveillance data from 23,168 subjects in the National Health and Nutrition Examination Survey (NHANES) 1999-2010 was used to examine the role dietary fiber plays in heart health.

In the current study investigators have taken a closer look at possible sex, age, racial/ethnic, and socioeconomic disparities in dietary fiber consumption, as well as examined the association between dietary fiber intake and various cardiometabolic risk factors.

Dietary fiber, which previous studies have shown may assist in lowering blood pressure, cholesterol levels, and inflammation, is thought to play an important role in reducing cardiovascular risk. Despite this knowledge, investigators found that dietary fiber intake was consistently below recommended intake levels for NHANES participants.

The Institute of Medicine defines recommended intake levels according to age and sex: 38g per day for men aged 19-50 years, 30g per day for men 50 and over, 25g for women aged 19-50 years, and 21g per day for women over 50. Using data from NHANES 1999-2010, the study reveals that the mean dietary fiber intake was only 16.2g per day across all demographics during that time period.

"Our findings indicate that, among a nationally representative sample of nonpregnant US adults in NHANES 1999-2010, the consumption of dietary fiber was consistently below the recommended total adequate intake levels across survey years," says senior investigator Cheryl R. Clark, MD, ScD, Center for Community Health and Health Equity, Brigham and Women's Hospital and Harvard Medical School, Boston. "Our study also confirms persistent differences in dietary fiber intake among socioeconomic status and racial/ethnic subpopulations over time."

The research team found variations according to race and ethnicity, with Mexican-Americans consuming higher amounts of dietary fiber and non-Hispanic blacks consuming lower amounts of dietary fiber compared with non-Hispanic whites.

The study highlights the importance of increasing dietary fiber intake for US adults by showing a correlation between low dietary fiber and an increased risk for cardiovascular risk. Participants with the highest prevalence of metabolic syndrome, inflammation, and obesity were in the lowest quintile of dietary fiber intake.

"Overall, the prevalence of the metabolic syndrome, inflammation, and obesity each decreased with increasing quintiles of dietary fiber intake," comments Clark. "Compared with participants in the lowest quintile of dietary fiber intake, participants in the highest quintile of dietary fiber intake had a statistically significant lower risk of having the metabolic syndrome, inflammation, and obesity."

This new data analysis emphasizes the importance of getting adults across diverse ethnicities to increase their dietary fiber intake in order to try and mitigate the risk for cardiovascular damage.

"Low dietary fiber intake from 1999-2010 in the US and associations between higher dietary fiber and a lower prevalence of cardiometabolic risks suggest the need to develop new strategies and policies to increase dietary fiber intake," adds Clark. "Additional research is needed to determine effective clinical and population-based strategies for improving fiber intake trends in diverse groups."

Eating more fiber may lower risk of first-time stroke

Study Highlights:

- Eating foods with more fiber was linked to a lower risk of first-time stroke.

- Every seven-gram increase in total dietary fiber was associated with a 7 percent lower risk of first-time stroke.

- The results reinforce the importance of a diet that includes at least 25 grams of fiber daily.

Eating more fiber may decrease your risk of first-time stroke, according to new research in the American Heart Association journal Stroke.

Dietary fiber is the part of the plant that the body doesn’t absorb during digestion. Fiber can be soluble, which means it dissolves in water, or insoluble.

Previous research has shown that dietary fiber may help reduce risk factors for stroke, including high blood pressure and high blood levels of low-density lipoprotein (LDL) “bad” cholesterol.

In the new study, researchers found that each seven-gram increase in total daily fiber intake was associated with a 7 percent decrease in first-time stroke risk. One serving of whole wheat pasta, plus two servings of fruits or vegetables, provides about 7 grams of fiber, researchers said.

“Greater intake of fiber-rich foods – such as whole-grains, fruits, vegetables and nuts – are important for everyone, and especially for those with stroke risk factors like being overweight, smoking and having high blood pressure,” Diane Threapleton, M.Sc., and Ph.D. candidate at the University of Leeds’ School of Food Science & Nutrition in Leeds, United Kingdom.

Researchers analyzed eight studies published between 1990-2012. Studies reported on all types of stroke with four specifically examining the risk of ischemic stroke, which occurs when a clot blocks a blood vessel to the brain. Three assessed hemorrhagic stroke, which occurs when a blood vessel bleeds into the brain or on its surface.

Findings from the observational studies were combined and accounted for other stroke risk factors like age and smoking.

The results were based on total dietary fiber. Researchers did not find an association with soluble fiber and stroke risk, and lacked enough data on insoluble fiber to make any conclusions.

The average daily fiber intake among U.S. adults is lower than the American Heart Association’s recommendation of at least 25 grams per day. Six to eight servings of grains and eight to 10 servings of fruits and vegetables can provide the recommended amount.

Most people do not get the recommended level of fiber, and increasing fiber may contribute to lower risk for strokes,” Threapleton said. “We must educate consumers on the continued importance of increasing fiber intake and help them learn how to increase fiber in their diet.”

In the United States, stroke is the fourth leading cause of death, killing more than 137,000 people annually. Among survivors, the disease is a leading cause of disability.

In addition to following a nutritious diet, the American Heart Association recommends being physically active and avoiding tobacco to help prevent stroke and other heart and blood vessel diseases.