Whole-grain front-of-pack messaging has rocketed recently, but is there any real evidence behind such consumer acceptance? What grain will catch the next wave of better-for-you marketing? Mark J Tallon, PhD, investigates why grain claims are set to be a market favourite in '09
The benefit of grains has been well established in the scientific literature as well as with consumers — 72 per cent of consumers now associate whole grains with cardiovascular benefits, and 86 per cent with intestinal health, according to the International Food Information Council (IFIC). Studies show that whole-grain consumption lowers heart-risk failure, and can significantly decrease abdominal fat in those consuming whole rather than refined grains.1,2
The evidence for grains is such that the FDA has granted foods containing more than 51 per cent whole grains the right to carry a heart-health claim. Clearly there is a vast range to develop healthy consumer-food options, with powerful FDA-approved front-of-pack statements. The following provides a microreview of the latest grain offerings and their influence on human health.
Amaranth is a grain indigenous to Mexico that has been cultivated since Aztec times. Its resurgence is due in part to the commercialisation of exotic foods — amaranth and other so-called ancient grains fit this trend. A protein content of 16 per cent and a selection of unique phytochemicals make amaranth a compelling functional food. It has been linked with a positive effect on hypertension, coronary heart disease and immune response.3,4 A three-week, controlled clinical trial assessed the effect of amaranth oil in 125 patients with cardiovascular disease.5 The patients were randomised to a low-salt diet plus 3-18mg/day amaranth oil or only a low-salt diet. The amaranth oil group had reduced cholesterol levels in blood serum, and also reduced blood pressure. Other effects included reduced markers of oxidative stress and enhanced immunity.
Although cardiovascular health is a major category for amaranth, there are potentially other applications based on its phytochemical composition. One of its more significant bioactives is a lunasinlike peptide, which may have hypertensive effects. Another is the triterpene compound squalene, which is highly resistant to oxidation and a strong antioxidant. Recent hypotheses are beginning to link squalene to dermal health,6 and given the high levels of squalene in amaranth, it would not be surprising to see it utilised in cosmetics applications, food and more.
Chia (Salvia hispanica) is an excellent source of omega-3 fatty acids, fibre, protein and antioxidants. Like amaranth, chia is an ancient grain and marketed as such, though clinical-trial evidence is relatively new.
In January 2009, researchers from Argentina investigated the benefits of chia seed on dyslipidaemia and insulin resistance (IR).7 In a three-month feeding study, a sucrose-rich diet was used to bring about IR in rats. Once IR and dyslipidaemia were present at the end of three months, chia was given to half the group in place of fat, while the control group had sucrose replaced with maize starch. Chia prevented the onset of dyslipidaemia and IR. Additionally, chia reduced the visceral adiposity present in the sucrose-supplemented rats.
In a human trial, researchers found chia added to conventional diabetes treatment improved major and emerging cardiovascular risk factors in individuals with type 2 diabetes.8 Twenty well-controlled subjects with type 2 diabetes were randomly assigned to receive either 37g/day chia or wheat bran (control) for 12 weeks while maintaining their conventional diabetes therapies. The chia group had reduced systolic blood pressure (SBP) and C-reactive protein, a marker of inflammation. Chia also significantly decreased A1C (glycated haemoglobin) and fibrinogen compared to baseline. For more, see sidebar.
Tef (Eragrostis tef) is one of the principal sources of nutrition for two-thirds of the population in Ethiopia, where it is used to make flatbread. Unlike the peppery taste from amaranth, tef is a sweet-tasting grain, molasseslike in flavour. This taste provides its favour with Western consumers. In a recent clinical trial, researchers investigated whether the naturally gluten-free cereal is safe when used by celiac disease (CD) patients.9
In March 2006, all 7,990 members of the Dutch Celiac Disease Society were invited to complete a questionnaire on celiac-symptom development after tef consumption. Thirty-six percent responded to the first questionnaire, of whom 53 per cent consumed tef and 15 per cent reported complaints. For the second questionnaire, out of the 1,828 participants willing to complete it, 1,545 had biopsy-proven CD. Of these, 66 per cent used tef and 17 per cent reported symptoms after consumption. The percentage for symptoms was significantly lower than that in patients without tef consumption. The take-home was that CD patients using tef reported a significant reduction in symptoms, possibly related to a reduction in gluten intake or to an increase in fibre intake.
Wheat is the perennial whole-grain favourite for breads. Wheat is a generic term for a class of whole-grain varieties based around endosperm hardness, colour and season of growth.
A 2008 study from the United Kingdom investigated one of the most interesting fields of human health — the modulation of the intestinal flora (gut health).10 Epidemiological studies have shown an inverse association between whole-grain intake and chronic-disease risk. According to authors of the following trial, the relationship of whole grains and disease may be mediated by the prebiotic modulation of gut microbiota.
A double-blind, randomised, crossover study was carried out in 31 volunteers who consumed 48g/day breakfast cereals composed of either wheat germ or wheat bran in two three-week study periods, separated by a two-week washout period. The results demonstrated a significant increase in the numbers of faecal bifidobacteria and lactobacilli following wheat-germ ingestion compared with wheat bran. Additionally, both cereals led to a significant reduction in total cholesterol. No adverse intestinal symptoms were reported, and wheat-bran ingestion increased stool frequency.
Despite the vast selection of grains — including flax, sunflower, barley, quinoa, triticale and hemp — consumers are still relatively undereducated in relation to the specific health benefits of whole grains. More important is consumer identification of correct intake. Although IFIC's recent survey results show that consumers are listening to the cardio benefits, secondary benefits relating to whole-grain macronutrient (satiety) and micronutrient (antioxidant) content are commercially underexploited.
In 2005, the Dietary Guidelines for Americans recommended that people make up more than half their grain consumption from whole grains (equivalent to three servings per day). However, these guidelines are confusing, as the reference dose is based on 'ounce-equivalents' — a one-ounce equivalent for grains is any food that is equal to a slice of bread. In order to overcome this confusion the Whole Grain Council has created a packaging symbol called the 'whole-grain stamp' that helps consumers identify which products contain one of the recommended three servings a day. More than 1,800 products now carry the stamp, which, when used in conjunction with the FDA-approved health claim and new research, should maintain the upward trend evident in the ever-growing whole-grain market.
Mark J Tallon, PhD, is chief science officer of NutriSciences, a London-based consultancy firm specialising in health-claim substantiation, product development and technical writing. www.NutriSciences.net
1. Nettleton JA, et al. Incident heart failure is associated with lower whole-grain intake and greater high-fat dairy and egg intake in the Atherosclerosis Risk in Communities (ARIC) Study. J Am Diet Assoc 108:1881-7.
2. Katcher HI, et al. The effects of whole grain enriched hypocaloric diet on cardiovascular disease risk factors in men and women with metabolic syndrome. Am J Clin Nutr 87: 79-90.
3. Hibi M, et al. Amaranth Grain Inhibits Antigen-Specific IgE Production Through Augmentation of the IFN-gamma Response in vivo and in vitro. Cytotechnology 2003;43(1-3):33-40.
4. Martirosyan DM, et al. Amaranth oil application for coronary heart disease and hypertension. Lipids Health Dis 2007;5:6-11.
5. Silva-S?nchez C, et al. Bioactive peptides in amaranth (Amaranthus hypochondriacus) seed.J Agric Food Chem 2008;56(4):1233-40.
6. Huang ZR, et al. Biological and pharmacological activities of squalene and related compounds: potential uses in cosmetic dermatology. Molecules 2009 Jan 23;14(1):540-54.
7. Chicco AG, et al. Dietary chia seed (Salvia hispanica L.) rich in alpha-linolenic acid improves adiposity and normalises hypertriacylglycerolaemia and insulin resistance in dyslipaemic rats. Br J Nutr 2009;101(1):41-50.
8. Vuksan V, et al. Supplementation of conventional therapy with the novel grain Salba (Salvia hispanica L.) improves major and emerging cardiovascular risk factors in type 2 diabetes: results of a randomized controlled trial. Diabetes Care 2007; 30(11):2804-10.
9. Hopman E, et al. Tef in the diet of celiac patients in the Netherlands. Scand J Gastroenterol 2008; 43(3):277-82.
10. Costabile A, et al.Whole-grain wheat breakfast cereal has a prebiotic effect on the human gut microbiota: a double-blind, placebo-controlled, crossover study.Br J Nutr 2008; 99(1):110-20.