Researchers and public health organizations have long praised the benefits of fiber, but how much fiber should we consume? As quoted in Medical News Today, this question has prompted the World Health Organization (WHO) to conduct a new study.
The results were published in the journal The Lancet. The new study aims to help develop new guidelines for consumption of dietary fiber, and reveals which carbohydrates protect the most from non-communicable diseases and can prevent weight gain.
Non-communicable diseases are also called chronic diseases. They usually last for a long time and develop slowly. According to WHO, there are four main types of non-communicable diseases, namely cardiovascular disease, cancer, chronic respiratory disease, and diabetes.
Jim Mann from the University of Otago in New Zealand is the research writer, whereas Andrew Reynolds at the Dunedin Medical School, Otago, was the first author of this paper.
Mann explained the motivation for this study by saying, previous reviews and meta-analyzes usually examined one indicator of the quality of carbohydrates and a number of diseases so that it was impossible to determine which foods were recommended to protect against various conditions.
To find out, the researchers conducted a meta-analysis of observational studies and clinical trials. Daily intake of 25-29 grams of fiber is ideal. Reynolds and colleagues examined data included in 185 observational studies totaling 135 million people per year and 58 clinical trials that recruited more than 4,600 people. The study analyzed lasted almost 40 years.
Scientists investigate the incidence of certain chronic diseases, as well as the early death rates due to the disease. These conditions are coronary heart disease, cardiovascular disease, stroke, type 2 diabetes, colon cancer, and various cancers related to obesity, such as breast cancer, endometrial cancer, esophageal cancer, and prostate cancer.
Overall, the study found people who consumed the most fiber in their diet were 15-30 percent less likely to die prematurely due to any cause or cardiovascular condition, compared with those who consumed the least fiber.
Eating fiber-rich foods is associated with a lower risk of coronary heart disease, stroke, type 2 diabetes, and colon cancer. Fiber-rich foods include whole grains, vegetables, fruits, and nuts, such as peas, beans, lentils, and beans.
The analysis also revealed that the amount of fiber that people should consume every day to get these health benefits is 25-29 grams. For comparison, adults in the United States consume an average of 15 grams of fiber every day.
The authors also suggest consuming more than 29 grams of fiber per day can produce more health benefits. However, they cautioned, while the study itself found no detrimental health effects from consuming fiber, eating too much could damage people who lack iron or minerals.
“Eating large amounts of seeds can further deplete iron from the body,” the researchers said.
Finally, the clinical trials included in this study also revealed that consuming more fiber was strongly associated with lower body weight and lower cholesterol levels.
Why is fiber so good?
“The health benefits of fiber are supported by more than 100 years of research on chemistry, physical properties, physiology, and their effects on metabolism,” Mann said.
He also explained that whole foods are high in fiber which requires chewing and maintaining a lot of structure in the intestine can increase satiety and help control weight and can positively affect fat and glucose levels.
The breakdown of fibers in the large intestine by occupying bacteria has extensive additional effects including protection from colorectal cancer. “Our findings provide convincing evidence for nutrition guidelines to focus on increasing dietary fiber and replacing processed grains with whole grains.
“This reduces the risk of incidents and deaths from a variety of important diseases,” said Jim Mann.