Shaun Ward MSc ANutr
Quinoa is a pseudo-grain consumed as a dietary staple in South America but is now gaining recognition worldwide as a classified ‘superfood’.
Pseudo-grains are seeds from shrubs or bushy plants, unlike more traditional grains which belong to the grass family; wheat, rice, oats, barley.
Quinoa has a higher nutritive value compared to traditional cereals which have led to its rise in consumption among health-conscious individuals.
Quinoa is both dense in macronutrients (protein, carbs, fats) but also in micronutrients such as vitamins, minerals, and polyphenols.
Polyphenols - including phenolic acids, flavonoids, and tannins – are plant metabolites which have shown to lead to diverse physiological health benefits, including antimicrobial, antioxidant, anti-inflammatory, anti-tumor, and anti-carcinogenic effects.
1. It Has Antioxidant Properties
Some antioxidant components of quinoa are the phenolic, non-phenolic, and polyunsaturated fat contents, based on antioxidant activity experiments.
The phenolic substances in particular have demonstrated to elevate the expression of certain antioxidative enzymes that are able to protect the human organism, such as glutathione peroxidase and catalase.
Protection from these antioxidant enzymes is given by their ability to scavenge free radicals and neutralize reactive oxygen species that would otherwise induce oxidative stress and cell damage.
Studies also suggest quinoa may be able to regenerate antioxidant species that can then continue to fight off free radicals and protect against tissue damage .
Other components of quinoa also contribute to its antioxidative effects such as ascorbic acid, phytic acid, α-tocopherol, β-carotene, and saponins – which are non-phenolic compounds.
Although the specific components have not been pinpointed, some fractions of the quinoa seed have shown to significantly inhibit the production of reactive oxygen species in the first place, with a particular noted benefit on preventing skin aging . However, this has only been shown in cell culture studies – an artificial environment in a lab - and should be interpreted with caution.
Based on the findings that quinoa can reduce free radical production, and simultaneously scavenge those that are produced, it seems a great antioxidant that should be included in the diet.
2. It May Assist With Weight Loss
The high protein and dietary fiber content make quinoa an ideal food to include in weight loss diets as it will suppress hunger and thus reduce total energy intake.
Fiber is a dietary substance that is resistant to digestion and slows gastric emptying (time for food to empty from the stomach), and has been repeatedly found to increase satiety from a meal.
In terms of protein, positive alterations of sensory and cognitive signals can reduce an individual’s perception of hunger. In addition, protein has demonstrated an appetite suppressant effect via reducing neuropeptide hormones, such as ghrelin, which would typically signal hunger.
Quinoa may also decrease food intake by making beneficial changes to the expression of certain gut hormones.
In particular, quinoa intake can raise cholecystokinin levels – a gut hormone which aids digestion – which has shown to result in a feeling of satiety.
New data even suggests quinoa may influence DNA, speculating that it decreases the expression of fat storage genes such as lipoprotein lipase that will in turn assist weight loss .
Overall, the combination of protein, fiber, and the effect on gut hormones, are the main reasons why preclinical trials show quinoa can effectively decrease body fat levels – although more human research is needed.
3. It Could Be Helpful For Lowering Cholesterol
In animal studies, the inclusion of quinoa in the diet has a significant effect on reducing cholesterol levels in as little as 15 days .
This reduction in cholesterol from quinoa seems to be primarily on LDL-cholesterol levels (‘bad’ cholesterol), as opposed to HDL-cholesterol (‘good’ cholesterol).
This would make it an ideal food for individuals aiming to prevent atherosclerosis (plaque build-up in the arteries) and cardiovascular disease, as cholesterol levels are closely tied to these diseases.
It has been proposed that certain types of proteins present within the quinoa seed facilitate a decreased synthesis of cholesterol in the liver, although this is yet to be confirmed.
If this is the case, it would act via a similar mechanism to that seen in other food components such as β-glucans, found in oats, which have greater established research for their effect in decreasing cholesterol levels.
4. It Contributes Greatly To Your Nutrient Requirements
Quinoa contains a great variety of high-quality protein, dietary fiber, vitamins and minerals that will have a significant contribution towards reaching daily recommended intakes.
This makes it a great food to avoid nutrient deficiencies and any health issues that these deficiencies would cause.
The nutrient content in 1 cup (185 grams) of cooked quinoa :
- Protein: 8 grams
- Fiber: 5 grams
- Manganese (58% RDA)
- Magnesium (30% RDA)
- Phosphorus (28% RDA)
- Folate (19% RDA)
- Copper (18% RDA)
- Iron (15% RDA)
- Zinc (13% RDA)
- Potassium (9% RDA)
- B Vitamins (>10% RDA)
5. It's Better than Other Grains for Blood Sugar Levels
Quinoa has less impact on raising blood sugar and insulin levels from a meal when compared to more popular refined grains .
In particular, it is especially useful for diabetics looking to improve their glucose tolerance and incorporate grain products into their diet.
The glycemic index - the relative ability to increase the level of glucose in the blood - of quinoa is 53, which is defined as “low”. This is similar to that of oatmeal, yams, and muesli.
Quinoa has such a good effect on blood sugar as it contains a high amount of dietary fiber. Per cup, there is ~20 grams of fiber, which is more than double what most grains can offer.
Dietary fiber slows down the digestive processes of a meal and leads to a lesser impact on spiking blood sugar levels.
Quinoa has some promising research on its ability to help with weight loss, lower cholesterol, fight cell damage, and stabilize blood sugar levels.
However, much of this data has only been studied in animals and it is not yet conclusive what the beneficial effects are in humans.
Although judging by the nutrient composition of quinoa, there is no reason why it cannot be a healthy addition to any diet.