The prevalence of diabetes is increasing dramatically and the disease has become a global health problem. Worldwide, 387 million people have diabetes, 8.3 percent of the world population, and prevalence is expected to rise to 592 million by 2035 (International Diabetes Federation, 2014). Furthermore, an additional 316 million people have impaired glucose tolerance. The International Diabetes Federation estimates that 179 million people with diabetes are undiagnosed. Diabetes impacts health in the U.S., the country with the third highest prevalence after China and India, at an estimated cost of $245 billion for diabetes-related health expenditures (American Diabetes Association, 2012).
Diet strongly influences risk factors for non-communicable diseases (NCDs) such as diabetes, obesity, and coronary heart disease by impacting blood glucose and lipid levels. According to the World Health Organization, NCDs, led by cardiovascular diseases, cancers, respiratory diseases, and diabetes, kill 38 million people annually, with these top four accounting for over 80 percent of all NCD deaths (WHO, 2015). Dietary measures can reduce hyperglycemia and impact not only diabetes incidence but also incidence of cardiovascular and other disease for which diabetes is a risk factor.
Consistent with U.S. and international dietary guidelines, carbohydrates contribute the highest percentage of calories in a typical American diet. Carbohydrates directly affect post-prandial blood glucose and insulin levels as a function of their digestibility and absorption properties. Hence, products with more fiber and less sugar can lead to a lower rise in blood sugar. Blood glucose and insulin can be expected to rise most after a meal that provides a large quantity of readily digestible carbohydrates, setting off a cascade of metabolic responses that cause the body to store rather than expend fat calories. These metabolic responses include increased use of carbohydrates as fuel in the muscle, increased fat generation in the liver, and increased fat deposition in fat stores.
A 2013 scientific consensus summit examined the health benefits of reducing blood sugar levels and the resultant insulin response. Attended by research leaders in the field of glycemic index (GI) and glycemic load (GL), the conference generated a consensus statement acknowledging that reducing postprandial glycemic response has beneficial physiological effects (Augustin et al, 2015). The summit concluded that evidence supports a role for diets low in GI/GL to improve glycemic control in people with type two and type one diabetes, thereby reducing the risk of type two diabetes and coronary heart disease. The consensus statement also notes probable evidence that diets low in GI/GL reduce total body fat mass and support body weight management. Reduction in postprandial glycemic response can be accomplished by including in the diet carbohydrate foods with a low rather than high GI and/or GL.
Considerations in Blood Glucose Management
Blood glucose management is relevant for all age groups and encompasses short- and long-term factors. Short-term, i.e., post-prandial, several factors, namely, foods consumed and blood glucose response to those foods, insulin release, the ratio of carbohydrate and fat oxidation, and the second meal effect, impact the rise and fall of blood sugar levels. Longer-term factors include blood glucose control, insulin sensitivity, lipid metabolism, energy storage, weight management, and body composition, including fat distribution.
Carbohydrate quantity, quality, and the food matrix, including fat content, affect glycemic response to carbohydrate-based foods. Fully digestible, “glycemic” carbohydrates are highly available for digestion and absorption in the small intestine. They supply energy and directly impact blood glucose levels; the vast majority of glycemic carbohydrates have a high to very high glycemic response. (an excemption is isomaltulose (Palatinose™)). Non-digestible, “non-glycemic” carbohydrates such as inulin-type fructans from chicory root travel virtually intact into the colon. They do not trigger a blood glucose rise and, in fact, lower the blood glucose response of the given food they are in.
Consumers present a potential challenge to health professionals and educators because they choose foods first on taste, followed by price and then healthfulness (IFIC, 2015). While nearly two-thirds of respondents to a HealthFocus International survey say they have a great deal of control over future health, only one-third choose healthy foods and beverages to ensure future good health (HealthFocus, 2015). Similar percentages are extremely or very concerned about diabetes and/or watch their sugar intake or take steps to lose weight. One in 10 switches the type of carbohydrates they eat.
Blood sugar management requires motivating consumers to make different food choices. Replacing some of the highly available carbohydrates in foods with the inulin-type fructans inulin and/or oligofructose can improve carbohydrate quality, reducing glucose release into the body, lowering GI/GL, and dampening blood glucose and insulin responses. Taste and cost, however, remain important for acceptance.
Studies Support a Role for Chicory
Inulin-type fructans from chicory root as a partial replacement for sugars have been shown to improve measures of blood glucose management in several human intervention studies and trials, including two studies conducted on behalf of BENEO following the EFSA Guideline gold standard methodology. Dose response relationship is linear and the lowest measured dose so far was at 20% replacement with sucrose. Evaluation of the relevant data by EFSA resulted in a positive opinion (EFSA, 2014). . Studies by Cani et al (2009), Russo et al (2010), Dehghan et al (2013), Pourghassem Gargari et al (2013), Dewulf et al (2013), and Dehghan et al (2014) all showed that supplementation with 10-11 g/day inulin or 16 g/day Orafti® Synergy1, a 50:50 combination of inulin and oligofructose, reduced fasting or post-prandial blood glucose as compared to control. The subjects in the Dehghan studies had type 2 diabetes. The systematic review and meta-analysis by Kellow and colleagues (2014) demonstrates significantly reduced postprandial glucose and insulin concentrations from daily supplementation with inulin-type fructans (Kellow et al, 2014).
New research is examining whether oligofructose (Orafti® P95) might increase insulin sensitivity. De Vadder et al (2014) not only confirmed that P95 contributes to a decrease in postprandial glycemia but also that the short-chain fatty acids (SCFAs) generated by bacterial fermentation of P95 activate intestinal gluconeogenesis (IGN) via a gut-brain neural circuit. It has been suggested that enhanced IGN plays a causal role in the metabolic benefits of fermentable fibers, including obesity reduction, improved glucose tolerance, and heightened insulin sensitivity.
EFSA Recognizes a Claim for Non-digestible Carbohydrates
In 2014, a panel of the European Food Safety Authority (EFSA) acknowledged a relationship between consumption of foods and beverages containing non-digestible carbohydrates and a reduction in postprandial glycemic responses based on data related to oligofructose. The Panel recognized that non-digestibility in the small intestine and a decreased amount of available carbohydrates when replacing sugars with such carbohydrates lowered postprandial glycemic and insulinemic responses, supporting a cause and effect relationship. An approved health claim in the EU related to this health benefit is on its way. In the United States, the type of claims covering these effects are structure/function claims. They can be used without pre-market approval if substantiated. Having in mind the strong data related to chicory root fiber more products have to be expected that help consumers in their healthy food choice.
Significant reduction of blood glucose and insulin responses occurs with partial replacement of sugars in foods and beverages with inulin-type fructans, in a dose-response relationship. Product nutrition is further improved because oligofructose and inulin add fiber and allow for a reduction in sugars, without compromising taste. Furthermore, Augustin et al conclude that inulin-type fructans show beneficial effects on biomarkers for long-term blood glucose management.