Quinoa is known for its high protein content, containing all essential amino acids, and being made of plant compounds that inhibit the digestion of fats and sugars in the gut, this could help to reduce spikes in blood glucose levels. It also contains numerous minerals, vitamins, and unsaturated fatty acids required to maintain optimal health. The high carb and fiber content paired with low simple sugar content is associated with a low glycemic level.
According to CDC statistics, diabetes affects 11.3% of the population in America, which is around 37.3 million people. 28.7 million people have been diagnosed with diabetes, and an estimated 8.5 million people remain undiagnosed. Roughly 96 million people have prediabetes, which is 38% of the adult population, and 26.4 million people (48.8%) aged 65+ have prediabetes. Type 2 diabetes causes millions of premature deaths every year, and the presence of prediabetes increases the risk of type 2 diabetes by 70%, with 10% developing the condition every year and the risk is even higher for those over the age of 65.
This study examined the effects of a quinoa-rich diet on mediating hyperglycemia and other metabolic risk factors. Glycemic data was collected by glucose sensors operating over extended periods of time with regular prespecified recording points that could be analyzed using the functional data analysis approach to yield glucose concentrations over time.
All of the participants in this pilot study were aged 65+, without a history of diabetes, and fasting glucose levels were between 100-125 mg/dL. The participants ate grains, legumes, and tuber daily while also consuming quinoa, quinoa flakes, and quinoa flour as well as biscuits, brioche, sponge cake, baguettes, sliced bread, and pasta which all had a quinoa content of 70% or greater.
During the initial four weeks, the participants consumed their regular diets, then they were switched to the quinoa-based diet for the following four weeks, during this time all grains, grain-based products, legumes, and tubers were substituted with quinoa-based products without changing the overall composition of nutrients with exception to the cereal. During the study, all food products were provided to the participants who commonly consumed them. Additionally, eight recipes were introduced to the participants using quinoa substitutions.
At the beginning of the study most of the participants had an overweight profile, and hypertension, 45% had high blood lipids, and 33% had one or more close family members with disease. At the end of the study glucose levels were reduced before and after the quinoa-based diet, and glycated hemoglobin levels were reduced by the end of the study, as was weight and waist circumference by slight decreases.
During the regular diet part of the trial, the participants consumed more carbs, but during the quinoa-based diet period, they consumed more total lipids and saturated fats as well as increased levels of cystine, arginine, glutamic acid, and proline.
Additional analysis revealed that multiple nutrients were associated with enhanced or reduced glucose concentrations: Gamma-tocopherol, soluble fiber insoluble dietary fiber, and ORAC were associated with enhanced glucose concentrations, while fatty acids, fructose, citric acid, cellulose, phytic acid, omega-6 PUFA, theobromine, and the proportion of total energy from proteins had a link with reduced glucose concentrations.
The nutritional profile of quinoa accounts for the difference in nutritional intake between the two diet phases. Consuming more carbs increases insulin levels, and fat storage and reduces the metabolic rate causing a cycle of fat accumulation. A high-fat diet with the same amount of calories reduces insulin secretion by triggering fat turnover in the cells making free fatty acids available for use in energy production. Dietary proteins also enhance the building of lean muscle during weight loss which also helps to expend more energy and improve the overall body composition.
It is more important to improve the quality of diet than to reduce body weight to achieve beneficial metabolic outcomes in older prediabetic people, the stabilization of blood sugar fluctuations during the quinoa-based diet may be due to the low glycemic index. Higher intake and increased fat content of the quinoa-based diet were correlated with reduced glucose levels, which is likely due to other nutrients in the quinoa diet that prevent glycemic spikes.
Although these results are positive, additional research is required with more participants for longer periods of time to make definitive conclusions. Despite the limitations, findings displayed clear potential for delaying the development of type 2 diabetes in prediabetic individuals.
“A diet rich in quinoa reduces postprandial glycemia, thanks to the joint action of different nutrients and the suppression of others consumed in a regular diet, which could apply a brake to the progression to T2D.”