“Not possible” to say for sure that ancient wheats protect better against disease: study

27 Oct 2017 --- It is not possible to definitively conclude that ancient wheat varieties are superior to all modern counterparts in reducing chronic disease risk, according to a summary of all in vitro, ex vivo, animal and human studies that have thus far been published. The review, which cites the limited number of human trials, is published in The Journal of Nutritional Biochemistry.

Wheat is the major staple food in many diets, the review authors note. They add that in 2016, the global production of wheat exceeded 749 million tons, making it the second most-cropped cereal after maize.

Based on the increase in worldwide mortality attributable to diet-related chronic diseases, there is an increasing interest in identifying wheat species with greater health potential, more specifically for improved antioxidant and anti-inflammatory properties.

In particular, ancient varieties (defined as those species that have remained unchanged over the last 100 years) are gaining interest, since several studies have suggested that they present a healthier nutritional profile than modern wheats, the review authors point out. This is reflected in ancient grains’ popularity in the nutrition space, and Innova Market Insights recently reported that ancient grains are maintaining momentum in global food and drinks launches. 

Their manuscript reviews the nutritional value and health benefits of ancient wheats varieties, providing a summary of all in vitro, ex vivo, animal and human studies that have thus far been published.

Inconclusive differences
Differences in chemical composition – and biochemical and clinical implications – of emmer, einkorn, spelt, khorasan and various regional Italian varieties were looked at by the researchers. Although many studies based on in vitro analyses of grain components provide support to the premise of a healthier nutritional and functional potential of ancient wheat, other in vitro studies performed are not in support of an improved potential of ancient varieties.

For example, several studies have explored the immune toxicity profile for celiac disease of ancient wheat cultivars with respect to modern varieties, but in vitro and ex vivo studies have provided conflicting results thus far.

Data derived from a limited number of studies indicate that, on average, ancient wheats, though not all the varieties, express lower levels of immunoreactive T-cells. Research using protein extracts from both ancient and modern wheat varieties demonstrated a large variation in immune responses depending on genotype, as measured by epitope-specific T-cell responses.

The cytotoxicity of spelt was found to be similar to common wheat (Triticum aestivum), whilst emmer generally appeared to be less immunoreactive, but more immunoreactive than einkorn. Despite lower reactivity, einkorn and emmer nonetheless produced reactions in 25 percent to 38 percent of tested patients' T cells. Such variability underscores the fact that wheat varieties are safe for individuals with celiac disease, the report points out.

In the light of existing evidence derived from in vivo experiments, the researchers conclude that the ancient wheat varieties have shown convincing beneficial effects on various parameters linked to cardio-metabolic diseases such as lipid and glycemic profiles, as well as the inflammatory and oxidative status. However, given the limited number of human trials, it is not possible to definitively conclude that ancient wheat varieties are superior to all modern counterparts in reducing chronic disease risk.

The researchers believe that available information, though scarce, raises interesting considerations for deliberation, especially when drawing conclusions on health benefits. Given that there are no linear correlations between quantitative bioactive compound measurements and functional potential, it is suggested that the best option in investigating the functional potential of these varieties would be to include the use of cell model systems to screen for potential candidates, with follow-up trials on human subjects.