Weight Watchers made headlines late last year when it announced it was changing its 13-year-old Point system. The new PointsPlus system upends the way the weight-loss program assigns points to foods based on calories. In the new system, calories are not created equally: fat calories cost more than carbohydrate calories, for instance. Writers from the Washington Post, the Huffington Post and Salon bemoaned how the new point system is no longer assigning point to fruits, yet, the calories in fruit certainly count when it comes to the number on the scale.
A much-less-reported aspect of the new system is how it reduced the Points for fiber calories. In an explanation of the new system on its website, Weight Watchers said, It has been known for decades that the body has to work harder to process some foods more than others. For example, protein and carbohydrates rich in fiber take much more work to process than refined carbohydrates and fats. This means that some foods leave our bodies with fewer calories to use for fuel. It also stated Furthermore, research has also shown that some nutrients, particularly protein and fiber, provide greater satiety than others, such as sugars and fat.
The fruit change caused a mini uproar in the media; fibernot so much. This is because fiber benefits arent contentiousone would be hard pressed to say the calories in fiber arent balanced by its health benefits. In contrast, a Washington Post article said, Fruit doesn't pack enough nutritional punch to offset the sugar and calories it adds to our diets, according to some nutritionists.
Fiber is an essential nutrient without controversyeveryone agrees that our diets need plenty of it, said David Romeo, managing director, Nutraceuticals International. In an article featured on WebMD.com, Elaine Magee, MPH, RD, and Louise Chang, M.D., report that eating a high fiber diet has been shown to lower blood cholesterol levels, improve and prevent constipation and slow digestion. And according to Barbara Rolls, Ph.D., author of The Volumetrics Eating Plan, fiber can help us eat lessand lose weight. Any manufacturer who can offer products that can do all that will have a superior edge over all the competition.
Fibers benefits are mostly linked to digestive healthan October 2010 New Nutrition Business analysis of five case studies reported when consumers think of fiber, they think of digestive benefitsbut increasing fiber intake also increases heart health and reduces obesitytwo big problems facing Americans today. Fiber also touts many more benefits, according to Ram Chaudhari, Ph.D., FACN, CNS, Fortitechs senior executive vice president and chief scientific officer. The rationale for increasing fiber is to have a beneficial effect in transit time, normalize bowel function, normalization of blood lipids and some help in blood glucose normalization, he said. Many disorders are associated with inadequate consumption of dietary fiber. These include constipation, hemorrhoids, diabetes, cardiovascular disease (CVD), bowel cancer and obesity. Individuals who consume a fiber-rich diet may reduce the risk of developing these diseases through complex mechanisms that are still being researched.
Still, its a much told story: consumers are aware of the benefits of fiber, but they havent been able to add more fiber to their diets. The American Heart Association (AHA) claimed dietary fiber consumption in the United States averages about 15 g/d. However, the Institutes of Medicine (IOM) said fiber intake for adults 50 years and younger should be 38 g for men and 25 g for women, while for men and women older than 50, it is 30 and 21 g/d, respectively.
Low levels of intake and high health benefits have increased consumer demand for fortified foods and beverages and supplements with fiber. Market researchers rank digestive health among the top three trends in health and wellness for 2010, reported Sarah Staley, vice president business development, FrieslandCampina Domo. Consumer interest in products for digestive health is at an unprecedented level, not just in the United States, but globally. She added, This consumer demand for products with digestive health benefits is matched by the response from food and beverage manufacturers, with an estimated 40-percent increase in products launched with a digestive health related claim.
Along with consumer interest, that rise in product introductions may be due to technology development that allows for better-tasting fiber products. Unlike the gritty, dry breads of yore, fiber fortification offers more tasty choices. In recent years, the advances in processing stability for prebiotics like Vivinal® GOS along with improved taste and mouthfeel mean the number of potential end product uses has hugely increased, Staley said, referencing her companys product. Traditional delivery of prebiotics through supplements or powder mixes has now been surpassed by introductions of mainstream foods and beverages with prebiotics as an integrated component. This in itself is probably the biggest innovation as it makes the benefits of prebiotics accessible to consumers in the everyday foods they already purchase making it more likely they will consume adequate amounts for the associated health benefits on a daily basis.
Everyday foods that offer satiety are of great interest to weight managers, according to a consumer research study conducted across 11 countries in December 2010 by Solae. Taste was the most important product attribute in 10 out of 11 countries when choosing foods for weight management. Because fiber can increase satiety, it is safe to assume consumers would be interested in fiber fortification of everyday foods, as long as they taste good.
Thus, fiber is a popular addition to baked goods, juice-based beverages and dairy drinks. But, as David Peters, sales and marketing director, Biovelop AB, said, We are constantly impressed by the innovative delivery forms that our clients' New Product Development teams are coming up with. Low-fat dips, soups and meat products are just a small selection of the many areas in which PromOat is being used.
Added Chaudhari: Cereal-based products, confectionery, dairy products, dietary supplements, baby foods, beverages, bars, baked goods and even chocolate are all quite viable. However, manufacturers must remember the importance of the design of their product as it relates to the expectation of the consumer surrounding how that product should look, feel and taste.
The confluence of better products, increased interest and health benefits have helped to create a ripe market for fiber products. According to SPINS, fiber vitamins and supplements are up 51.5 percent compared to a year ago (52 weeks ending Oct. 30, 2010) in food, drug and mass markets excluding Wal-Mart. In the natural channel (excluding Whole Foods), fiber products and supplements were up 3 percent. Top fiber products were cereals (both hot and cold), pet foods, digestive aids and yogurt.
Fiber, whether found in cereals or whole fruits, is food material the body ingests, but does not digest. Dietary fiber is a general term that refers to a wide variety of compounds from plants that are resistant to the digestive enzymes produced by humans, Chaudhari explained. Because dietary fiber is resistant to digestive enzymes, it is not broken down or absorbed, which means it does not provide calories or energy to the body. In general, dietary fibers are various forms of complex carbohydrates that have varying abilities to swell by absorbing water into their structural matrix. Fibers that can actually dissolve in water, such as pectin, gums and psyllium, are referred to as soluble fiber. Insoluble fibers or roughage cannot dissolve in water, but they can absorb water. This causes them to swell, making them good bulking agents, which speeds up transit time and improves elimination.
Research has shown intake of fiber, whether soluble or insoluble, offers many benefits, including lowering blood pressure and serum cholesterol levels, improving glycemia and insulin sensitivity, significantly enhancing weight loss in obese individuals, and reducing the symptoms of a number of gastrointestinal (GI) disorders, including gastroesophageal reflux disease (GERD), duodenal ulcer, diverticulitis, constipation and hemorrhoids.1
Even though shoppers focus on digestion when they think fiber, numerous studies have shown its positive effects on weight management and heart health. Higher intake of dietary fiber, especially cereal fiber, helps prevent body weight and waist circumference gain.2 Obese individuals typically consume less fiber than normal-weight individuals.3,4 And, a review of studies in healthy adults demonstrated increased satiety, reduced hunger, reduced calorie intake and increased body-weight loss during consumption of higher-fiber diets.5 That review also found beneficial effects of fiber on calorie regulation occurred with both soluble and insoluble fibers, when using either foods naturally high in fiber or fiber supplements.
Fiber intake is also good for the heart, as studies suggest an inverse association between fiber intake and myocardial infarction in men,6 and higher fiber intake, particularly from cereal sources, reduced the risk of CVD in women.7 In young adults, high-fiber diets protected against obesity and CVD by lowering insulin levels in a population-based cohort study that lasted 10 years.8 And, fiber intake was inversely associated with serum C-reactive protein (CRP), a possible predictor of cardiovascular events, in a study using data from the National Health and Nutrition Examination Survey from 1999 to 2000.9 In 2010, Japanese researchers found dietary intakes of fiber, both insoluble and soluble fibers, and especially fruit and cereal fibers, may reduce risk of mortality from coronary heart disease (CHD), but vegetable fiber did not reduce the risk of mortality from CHD.10
Interestingly, fiber may also reduce the risk of cancer, according to a 2010 English study that found intake of fiber was inversely associated with the risks of colorectal and colon cancers.11
Soluble vs. Insoluble
While, the National Institutes of Health (NIH) noted both soluble and insoluble fibers are important for health, digestion and disease prevention, researchers and consumers are starting to make the distinction between the two.
For instance, soluble fiber reduced inflammation associated with obesity-related diseases and strengthened the immune system by increasing the production of an anti-inflammatory protein called interleukin-4 compared to a diet of insoluble fiber in a 2010 study.12 Researchers at the University of Illinois, Urbana, found a mice fed soluble fiber became less sick and recovered faster from endotoxin-induced sickness behaviors than mice fed insoluble fiber.
And unlike insoluble fiber, the short-chain fatty acids (SCFAs) produced during the fermentation of soluble fiber may attenuate inflammation associated with ulcerative colitis (UC)13,14 and Clostridium difficile.15
Product manufacturers are responding to this trend. While Packaged Facts determined sales of all fiber food and beverage ingredients will continue to increase indefinitely, formulators are increasingly embracing novel soluble fibers due to their versatility and invisible nature in applications that previously were not conducive to fiber enrichment. In September 2010, Packaged Facts predicted the novel fiber food ingredient category will increase its share of the market by more than 750 percent, jumping 35 percentage points from an almost 5-percent share in 2004 to a 39-percent share in 2014. Future projections are that the share for conventional, insoluble-type fibers will decrease by 41 percent, or 38 percentage points in 2014, while the share for the mostly new or newly refined conventional, soluble-type fibers will increase 64 percent, or almost 3 percentage points.
And its interesting to note FDA has approved heart health claims for three types of soluble fibersoat, psyllium and barleybut not for any insoluble fibers.
Indeed, a recent study found supplementing 6 percent oat beta-glucan concentrate, a soluble fiber, decreased net glucose flux, increased net SCFA flux and decreased peak insulin production in pigs compared to those that didnt consume the concentration.16 Previous studies have demonstrated oat beta-glucans decreased plasma total cholesterol, low-density lipoprotein (LDL) cholesterol, liver cholesterol concentrations and aortic cholesterol ester concentrations in hamsters.17 A 2010 study on bioactive beta-glucan (from OatWell) found consuming at least 3 g/day of oat bran may significantly lower LDL cholesterol levels by increasing the viscosity of intestinal contents in individuals who have high cholesterol levels.18
Biovelop offers PromOat beta glucan using a patented, chemical-free technology which enables it to separate the soluble fiber as a color- and taste-neutral powder, according to Peters. Along with cholesterol benefits, he said, PromOat can also help to lower blood pressure, regulate blood sugar, promote satiety and act as a prebiotic for improved gut health.
Also touting its fiber-cholesterol lowering connection, flax seed gum lowered LDL cholesterol from 110 mg/dl to 92 mg/dl (P=0.02) in type 2 diabetics,19 and a University of Toronto study found up to 50 g high-alpha-linolenic acid (ALA) flaxseed/d lowered serum total cholesterol by 9 percent and LDL by 18 percent.20 They also found fiber to be palatable, safe and nutritionally beneficial in humans by raising omega-3 fatty acids in plasma and by decreasing postprandial glucose responses. Peak blood glucose values were also improved after receiving a flax supplement in another Canadian study (6.6 mmol/L before the supplements compared with 6.9 mmol/L, P =0.05 after).21
Marilyn Stieve, business development manager, flax, Glanbia Nutritionals, added flaxseed is rich in fiber and antioxidants, as well as a great source of ALA omega-3s and phytoestrogens, and a GRAS (generally recognized as safe) ingredient with nutrient content claims allowed for ALA omega-3. Glanbias BevGrad, just one of its flaxseed ingredients, is a finely milled flaxseed-derived ingredient solution that can be formulated in beverages, without compromising taste or texture, she noted.
Like seeds, all fruit offers high amounts of fiber, but some are better used for the natural products industry. For instance, baobab contains not only soluble fiber, but also a blend of vitamins and minerals. Nutraceuticals International® LLC partnered with a direct manufacturer of Baozene®, a standardized Baobab fruit powder extract that uses a proprietary manufacturing process. Baozene is an all natural extract with a standardized 70-percent fiber content, Romeo said. Baozenes beauty is in its simplicitysince it is soluble in either hot or cold water, with Baozene fiber can be added to any manufactured product.
Manufacturers are swaying more toward soluble fibers, its true, but the biggest growth in this market is prebiotic fiber ingredients. While prebiotic sales in total were down 1.9 percent in the mass channel, vitamins and supplements with prebiotics were up 8.5 percent. Its a different story in the natural channel: prebiotic sales were up 18.1 percent. The top categories for prebiotics were pet products, yogurt, digestive supplements and cold cereals.
Prebiotics are non-digestible food ingredients that stimulate the growth of beneficial bacteria already present in the digestive tract. According to the International Scientific Association for Probiotics and Prebiotics (ISAPP), the most widely accepted prebiotics are fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS), and they suggest consumers look for FOS, inulin (a type of FOS), GOS or TOS (transGOS) on product labels. ISAPP cited a growing list of candidate prebiotics, such as polydextrose, soybean oligosaccharides, isomalto-oligosaccharides (IO), gluco-oligosaccharides, xylo-oligosaccharides (XOS), palatinose, gentio-oligosaccharides and sugar alcohols (such as lactitol, sorbitol and maltitol), with evolving scientific backing. ISAPP added it would take a large quantity of foods that naturally contain prebiotics to create a beneficial effect in humans, so the organization recommends foodstuffs fortified with prebiotics as a more realistic way to obtain them in the diet.
Both chicory root/inulin (compounded annual growth rate [CAGR] =42.3 percent) and FOS/fructan (CAGR=35.7 percent) continue to drive innovation in the fiber-enriched food marketplace, according to Packaged Facts. Part of the FOS family, inulin is a group of naturally occurring polysaccharides that has been shown to improve bone health by increasing calcium and other mineral absorption,22 and prevent chronic inflammatory intestinal disorders.23 Inulin and oligofructose, a subgroup of inulin, stimulate the growth of intestinal bifidobacteria and do not lead to a rise in serum glucose or stimulate insulin secretion.24 XOS from alkali-pretreated corncob and FOS from cane sugar have an ameliorating influence on metabolic abnormalities associated with diabetes, besides conferring an optimal milieu of lactobacilli and bifidobacteria.25 And adding IO supplementation to a low-fiber diet improved colonic microflora profile and bowel movement in constipated elderly subjects, with beneficial effects waning after the supplementation was discontinued.26
Though CAGRs for the period from 2005 to 2009 are not available for fiber food ingredients introduced during this time frame (e.g., GOS), they all doubled and some even tripled in volume sales once they were introduced to the marketplace, according to Packaged Facts.GOS inhibits the adherence of pathogens to the colonic mucosal lining, thereby enhancing the robustness of the colonic cell wall and supporting the bodys natural defenses, Staley said. The SCFAs produced by fermentation of Vivinal GOS aid in lowering colonic and fecal pH, further contributing to overall health of the colonic environment. She added GOS enhances mineral absorption, improves digestive health and may increase satiety.
According to Packaged Facts, growth of novel fiber food ingredients, which showed the greatest compounded annual growth rate (CAGR) (65.6 percent) for the five-year period from 2005 to 2009, was driven by polydextrose (CAGR=54.6 percent). Though available to the food-formulating industry for more than 25 years, it was in 2007 that polydextrose was approved for use as an ingredient in an extensive array of foods and beverages.
Of polydextrose, Michael Bond, senior business director of fibers, Danisco, said, This fiber is unique in that it is slowly and incompletely fermented throughout the colon. Some other leading soluble fibers are quickly and completely fermented in the upper portion of the colon, which has immediate and long-term digestive health implications. Rapid fermentation can case generation and acid accumulation, resulting in GI discomfort within hours of consumption, he noted. Longer-term benefits include a reduction in the production of carcinogenic compounds and increased levels of the beneficial bacteria that help to keep the colon healthy and strong. Daniscos polydextrose ingredient, Litesse® can be used in nutrition bars, beverages, yogurt and confections, he said, because it has similar functional properties as sugar, but not sweet so it can balance sweetness levels.
A study that combined 12 g polydextrose and 50 g glucose (as Litesse) found the combination increased frequency and ease of defecation, wet and dry fecal weight, SCFA production and the presence of lactobacillus and bifidobacterium.27 Other research has shown Litesse is able to shorten the fecal transit time and to improve stool consistency in subjects suffering from constipation;28 increase fecal weight, decrease fecal pH and reduce clostridium perfringens; and aid the survival of a probiotic mixture in the human digestive tract.29
The benefits of combining prebiotics and probiotics are not exclusive to polydextrose. The result, called synbiotics, creates a healthy digestive tract. The activity of these ingredients in the colonic ecosystem results in beneficial physiological effects, Staley said. Prebiotics are fermented by probiotic bacteria in the gut to produce fermentation products like SCFAs, which in turn positively impact the health of the gut. Indeed, late in 2010, the American Academy of Pediatrics (AAP) reviewed literature and science on the health benefits of probiotics and prebiotics given to children in various delivery methods, and reported these stimulators of probiotic bacteria may have exhibited some long-term benefits in a small number of randomized controlled trials on atopic eczema and common infections in healthy infants.30 According to a study published in PLoS one in August 2010, a milk fortified with oligosaccharide and Bifidobacterium lactis significantly reduced dysentery, respiratory morbidity and febrile illness in children aged 1 to 4 years.31 And, the use of a probiotic mixture containing L. acidophilus, B. lactis and FOS was associated with significant clinical improvement in children with atopic dermatitis (AD), according to a paper presented at the New York Academy of Sciences symposium in June 2010.
Beyond children, synbiotics may improve the quality of life for celiac patients, as well as patients with associated diseases such as type 1 diabetes and other autoimmune disorders.32
Chr. Hansen combines probiotics with fibers, and Charlotte Beyerholm, marketing manager, human health and nutrition, Chr. Hansen, said the company is experiencing an increased demand in this product area. We have documented effect on constipation with some of our premium probiotic strains, e.g., BB-12®. Together with carefully select fibers, we have an excellent combination to tackle constipation.
Mixed with probiotics or not, prebiotics and fibers pose integrity and efficacy issues during formulation and processing. Some fibers and prebiotics are sensitive to pH and temperature, and can therefore break down during processing under extremes of pH and temperature, which has potential implications on efficacy, Bond said. This also applies to storage in products with low pHsome prebiotics will slowly degrade in very acidic conditions for example (<pH3). This obviously means that selection of the soluble fiber is important when prebiotic or fiber claims are used.
Chaudhari noted several prebiotic formulation challenges include: stability of nutrients at the end of shelf life, compatibility with other components of the finished product, possibility of cross contamination with pathogenic bacteria, solubility and digestive impact. And, thats not even to mention the organoleptic properties. Good taste, mouthfeel and viable cell counts in the finished product must be monitored throughout the shelf life of the product, he warned. The ultimate goal is to deliver a nutrient system that utilizes correct market forms of the highest quality without causing any adverse reaction in the finished product matrix.
High quality is a must for increasing demand for fiber and prebiotics; consumers insist on it, and why shouldnt they? With technological developments, fiber and prebiotic fortified everyday foods can easily fit in their schedules. To say this section of the natural product industry is the most important is not hyperbolic, according to Romeo. It is probably not an exaggeration to say that fiber is the future of the entire nutritional supplement industry. Scientific research corroborates what our own experience has already told usfiber is an extraordinary aid to health in the young and old alike, he said, adding, Fiber is essential in our individual futures and integral to our industrys future.
References are on the next page...
References for Bulking Up the Benefits of Fiber
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22. Scholz-Ahrens KE, Schrezenmeir J. Inulin and oligofructose and mineral metabolism: the evidence from animal trials. J Nutr. 2007 Nov;137(11 Suppl):2513S-2523S.
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25. Gobinath D, et al. Beneficial effect of xylo-oligosaccharides and fructo-oligosaccharides in streptozotocin-induced diabetic rats. Br J Nutr. 2010 Jul;104(1):40-7.
26. Yen CH,et al. Long-term supplementation of isomalto-oligosaccharides improved colonic microflora profile, bowel function, and blood cholesterol levels in constipated elderly people-A placebo-controlled, diet-controlled trial. Nutrition. 2010 Jul 10.
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