Pleasant Stone Farm Clinical Reports

A shift in gut microbial composition may explain the rising prevalence of chronic stomach upsets and even obesity among children in developed nations, suggests new research.

Diets high in fat, sugar and protein, and low in fiber have been associated with increased incidence of noninfectious intestinal diseases all over the world.

Researchers writing in the Proceedings of the National Academy of Science (PNAS), examined differences in gut microbiota in 14 healthy children in rural Burkina Faso and 15 healthy children in urban Italy in an effort to explain the role of gut bacteria in some of these chronic illnesses.

The Burkina Faso children ate a diet high in starch, fiber and plant polysaccharides, and low in fat and animal protein – a diet thought to be similar to that of early human settlements at the time of the birth of agriculture. The Italian children’s diet was typical of the developed world – high in animal protein, sugar, starch, and fat, and low in fiber.

The researchers, from the University of Florence, compared intestinal bacteria in the two populations and found that significant differences developed from the time that breast feeding ceased.

“Our results suggest that diet has a dominant role over other possible variables such as ethnicity, sanitation, hygiene, geography, and climate, in shaping the gut microbiota,” the authors wrote.

“We can hypothesize that the reduction in richness we observe in EU compared with BF children, could indicate how the consumption of sugar, animal fat, and calorie-dense foods in industrialized countries is rapidly limiting the adaptive potential of the microbiota.”

The Burkina Faso children’s diet was based on millet, sorghum, black eyed peas and vegetables, and contributed nearly twice as much fiber as the Italian children’s diet, leading the researchers to suggest that high fiber intake could play a central role in shaping gut microbiota.

And the ratios of gut bacteria for the Italian children have previously been linked to increased risk of obesity – perhaps providing a useful obesity biomarker, the researchers wrote.

They said that the study could prompt further research looking to clarify the relationship between differences in gut microbiota, health and disease, and could also lead to the development of novel probiotic products.

“Both in the Western world and in developing countries diets rich in fat, protein and sugar, together with reduced intake of unabsorbable fibers, are associated with a rapid increase in the incidence of noninfectious intestinal diseases,” they wrote. “…Reduction in microbial richness is possibly one of the undesirable effects of globalization and of eating generic, nutrient-rich, uncontaminated foods.”

Higher intake of both soluble and insoluble dietary fibers may reduce the risk of death from cardiovascular disease amongst Japanese men and women, according to a new study.

The study, which appears in the August issue of The Journal of Nutrition, followed 23,119 Japanese men and 35,611 women aged 40-79 years without a medical history of strokes or heart disease between 1988 and 1990.

All participants completed an initial 40-item food frequency questionnaire and had their soluble, insoluble and total dietary fiber and nutrient intake levels estimated. They were then grouped into five equal quartiles or groups depending on their estimated daily consumption of dietary fiber. The lowest-consuming first quartile ate a median of 6.8 g/d of total dietary fiber (TDF), while the highest fifth quarter consumed a median of 14 g/d.

Significant results

During a 14-year follow-up period the relation between dietary fiber intake and CVD was documented, with 2,080 of total participants dying from CVD – 983 from strokes, 422 from coronary heart disease (CHD) and 675 from other CVDs.

The study found that men and women consuming the most fiber were 18 percent less likely to die from cardiovascular disease than those consuming the least during the course of the study. The results were more striking when in specific relation to CHD, with men and women who consumed the most fruit fiber 58 percent and 45 percent less likely to die. Similar trends were noted for cereal-derived but not vegetable fibers over the same period.

“Our results constitute supporting evidence that higher intake of both insoluble and soluble fiber, especially fruit and cereal fibers, may contribute to the prevention of coronary heart disease in Japanese men and women,” the authors wrote.

They pointed out that epidemiologic studies in the west suggest that dietary fiber intake offers protection against cardiovascular disease. Mean Japanese dietary fiber intake (around 14 g/d) is similar to that of some western countries, but until now like studies have been rare in Asia, making their study interesting in a comparative context.

Research limitations

Statistical adjustments were made to account for other variables, given that men and women in the fifth quartile with the highest TDF intake were more likely than the first quartile to have better general diets, be around six to nine years older, be better educated, take more exercise and less likely to drink alcohol and smoke.

Nonetheless, the authors did not rule out the possibility that these other factors may have influenced disease incidence: The apparent protective effect of fiber on risk of CHD may be due to other health-related habits, such as regular exercise, no smoking and a high fish intake by persons who consume greater amounts of dietary fiber.”

Moreover, they conceded that some participants may have changed their diets over the years following the questionnaire in such a way that results were affected: “Multiple evaluations of diet over time are important to reduce measurement errors.”

Source: The Journal of Nutrition (140:1445-1453, 2010)
“Dietary Fiber Intake is Associated with Reduced Risk of Mortality from Cardiovascular Disease among Japanese Men and Women.”
Authors: E-S. Ehab, I. Hiroyasu, D.Chigusa, K.Shogo, T.Akiko, W.Yoshiyuki, W.Yasuhiko, W.Kenji, JACC Study Group.

Increased intakes of whole grains, and bran in particular, may reduce the incidence of hypertension in men, according to new findings from Harvard.

Data from over 30,000 men participating in the Health Professionals Follow-Up Study indicated that increased intakes of whole grains are associated with a 19 per cent lower incidence of hypertension.

The researchers, led by Alan Flint from Harvard School of Public Health, report their findings online in the American Journal of Clinical Nutrition.

“These findings have implications for future dietary guidelines and prevention of hypertension,” they wrote.

High blood pressure (hypertension),defined as having a systolic and diastolic blood pressure (BP) greater than 140 and 90 mmHg, is a major risk factor for cardiovascular disease (CVD) – a disease that causes almost 50 per cent of deaths in Europe, and reported to cost the EU economy an estimated €169bn ($202bn) per year.

While the potential heart health benefits of whole grains have been reported before, the Harvard researchers note that no studies have reported if the total grams of whole grains are linked to the risk of hypertension.

The 31,684 male health professionals aged between 40 and 75 without known hypertension, cancer, stroke, or heart disease were followed for 18 years. During this time, 9,227 cases of incident hypertension were documented.

Comparing the highest intakes of whole grains to the lowest intakes, the researchers calculated that whole grains were associated with a 19 per cent reduction in the incidence of hypertension.

When they subsequently looked at total bran, a 15 per cent reduction in the incidence of hypertension was observed for men with the highest intakes, compared to the lowest.

“In summary, we found an independent inverse association between intake of whole grains and incident hypertension in men,” wrote the researchers. “Bran may play an important role in this association,” they concluded.

Source: American Journal of Clinical Nutrition
Published online ahead of print, doi:10.3945/ajcn.2009.27460
“Whole grains and incident hypertension in men”
Authors: A.J. Flint, F.B. Hu, R.J. Glynn, M.K. Jensen, M. Franz, L. Sampson, E.B. Rimm