The ancient pseudograin quinoa has received much publicity lately as a “miracle food” because of its “remarkable” nutritional properties. DietDoc investigates.
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Your health questions answered
Quinoa is getting a lot of publicity lately as a “Miracle Food”. Health gurus sing its praises and Health24 users are constantly asking me about the use and nutritional value of this ancient, but newly “discovered” food. In reaction to one of the latest queries where a user asked if she could use quinoa in a slimming diet, I decided to investigate the literature about quinoa and share my findings.
Background
Quinoa (Chenopodium quinoa Willd), which was called “the mother of all grains” by the Incas, is regarded as a pseudograin because it is actually not a grass like our other grains (wheat, oats, rice, sorghum, and so on), and both its seeds and leaves can be eaten (Abugoch, 2009). It is, however, the dried seeds that are generally sold in supermarkets and health shops.
In the ancient civilisations of South America, quinoa was a valued staple food that was so highly regarded that is was deemed sacred. With the coming of the western Conquistadores who disliked the bitter taste of the seeds, quinoa was banned and it is only now after many centuries that we are “rediscovering” the nutritional value of this food.
Studies
Recent scientific studies have confirmed that quinoa “has remarkable nutritional properties, not only from its protein content (15%), but also from its great amino acid balance”. (Abugoch, 2009). Quinoa has been found to contain more lysine (an amino acid that is usually lacking in plant foods), than other cereals. Quinoa also contains minerals and vitamins and compounds such as polyphenols, phytosterols and flavonoids which all have antioxidant and protective functions.
It is evident that one cup of cooked quinoa is a rich source of energy supplying about 12% of the daily energy requirement for an adult woman who is not trying to lose weight and nearly 15% of the daily energy intake if a woman is on an energy-reduced diet.
So while quinoa is an excellent source of readily available fuel and will make an important contribution to the energy needs of anyone who has a high energy demand such as sportsmen and women, and very active children and teenagers, slimmers should only eat moderate portions to prevent weight gain. Have half a cup of cooked quinoa for breakfast to sustain you for the whole morning.
Macronutrients
Protein
With its high protein content (8g per cup) and the fact that quinoa protein contains the 9 so-called “essential amino acids” (including lysine) quinoa has an advantage above other grains and cereals and will be particularly useful in vegetarian and vegan diets as a source of protein (Ruales & Nair, 1992).
Carbohydrates and Dietary Fibre
Quinoa is also a rich source of carbohydrates and with a low glycaemic index (GI) of 18, it should provide sustained energy for longer than most other grains. If you suffer from insulin resistance or diabetes, it may be a good idea to have half a cup of cooked quinoa as an alternative to high-GI starches (Berti et al, 2005). The relatively high dietary fibre content will contribute to sustained energy and also prevent constipation.
Finally the carbohydrate in quinoa is gluten-free, which makes it an excellent choice for patients with gluten allergies or coeliac disease (Lee et al, 2009).
Fat
The total fat content of quinoa is low (4g per serving of 185g) and like all cereals and grains it does not contain any cholesterol.
Vitamins and Minerals
According to the SA Food Labelling Regulations any food that contains 15% of the RDA of a nutrient per serving can be regarded as a rich source of the specific nutrient. Quinoa is, therefore, a rich source of B vitamins, namely thiamin, riboflavin, vitamin B6 and folate.
This pseudograin is also rich in magnesium, phosphorus, potassium, zinc, copper and manganese. The low sodium content of quinoa is regarded as a nutritional advantage, but keep in mind if you add table salt to quinoa during cooking or food preparation, that the sodium content will increase accordingly.
Health risks?
With all its positive attributes, quinoa is a food that can be eaten by most people without risk, but it does contain compounds called oxalates which can be a problem for anyone suffering from oxalate kidney stones. If you are on an oxalate-reduced diet then it would be better to avoid eating quinoa (WHFoods Website, 2010).
In addition there will always be some individuals who are allergic to any given food and the first case report of an anaphylactic reaction to quinoa has already been reported in France (Astier et al, 2009). The saponins mentioned below, which need to be carefully rinsed off the seeds before cooking, are classified as toxic glycosides (AllergyNet, 2010). If you are allergic to alfalfa, hops or soybeans, which also contain saponins, then it is possible that you may have a similar reaction to quinoa.
How to prepare quinoa
According to the WHFoods website (2010), quinoa should be rinsed with water to remove the layer of soapy saponins that cover the seeds. This reduces the bitter taste and removes these potentially allergenic compounds.
Place the seeds in a fine-meshed sieve or colander and rub the seeds while rinsing under flowing water. Taste the washed seeds to see if they need additional rinsing.
Add one cup of quinoa seeds to 2 cups of water and bring to the boil. Reduce heat, place lid on saucepan and simmer for 15 minutes until the seeds become translucent.
References:
(Abugoch JLE (2009). Chapter 1 Quinoa (Chenopodium quinoa, Willd.) Composition, chemistry, nutritional & functional properties. Advances in Food & Nutrition Research, Vol 58:1-31; Allergy Net (2010). ; Astier C et al (2009). First case report of anaphylaxis to quinoa, a novel food in France. Allergy, Vol 64(5):819-20; Berti C et al (2005). Effect on appetite control of minor cereals and pseudocereal products. British Journal of Nutrition, Vol 94(5):850-8; Fresh Earth (2010). ); Lee AR et al (2009). The effect of substituting alternative grains in the diet on the nutritional profile of the gluten-free diet. Journal of Human Nutrition & Dietetics, Vol 22(4):359-363; Nutrition Data (2010). ; Ruales J, Nair BM (1992). Nutritional quality of the protein in quinoa (Chenopodium quinoa, Willd) seeds. Plant Foods for Human Nutrition, Vol 42(1):1-11; WHFoods (2010).
