Chia seeds originate from Central America and were eaten as part of the traditional Aztec diet. We’re now rediscovering the benefits of these tiny but nutritious seeds and they’ve become a favourite of nutritionists, healthy foodies and celebrities alike.
So what’s so great about the humble chia seed, and why should you be eating them? Here are some of their key ‘selling points’, followed by some of their potential health benefits.
High in omega-3s
Chia seeds are probably best known for their high content of omega-3 fatty acids. Together with flax seeds, they stand way above any other plant source of omega-3s: their oil is around 55–60% omega-3 alpha linolenic acid (ALA) , whereas walnut oil (often considered a good source too) is only around 10% omega-3s.
Omega-3s are associated with heart health, reducing cholesterol, supporting brain and eye health, and with reducing inflammation.
High in fibre
Chia seeds are one of the best sources of fibre we can eat. The whole (or ground) seeds are around 40% fibre, providing around 6 grams per tablespoon. In comparison, brown rice is only 3%, oats are 9%, and whole grain wheat flour is 12%. So even though the average serving of chia seeds is much smaller than any of these other foods, you’re still getting a lot of fibre!
High in calcium
Chia seeds are reported to contain over 600mg of calcium per 100g . That means a couple of tablespoons could give you up to 190mg of calcium – about as much as an average pot of yoghurt.
A source of complete protein
‘Complete’ proteins are protein foods that contain all the essential amino acids in the right proportion for human health. Many plant foods do not provide complete protein: for example, most grains are lacking in lysine, and most beans and pulses are low in methionine. This means that we need to eat other foods that are rich in that missing amino acid, to make up the deficit. But chia seeds do have all of those vital amino acids.
… And high in antioxidants
Chia seeds are a good source of antioxidants too. As well as antioxidant vitamin E, they contain a range of phytochemicals including the flavanols quercetin and kaempferol , which are found in high-antioxidant vegetables and fruits.
Another indicator of chia’s antioxidant value is its high ORAC rating. ORAC stands for ‘oxygen radical absorbance capacity’, and it’s a measurement of the antioxidant capacity of foods. Weight for weight, chia seeds actually have a similar ORAC value to blueberries and cranberries, and higher than blackberries and raspberries . However, we are likely to eat much less of them compared to fruit, so don’t go replacing your fruits and veggies with chia seeds!
So now we know what they contain, what does all this mean for our health?
Seven key health benefits of chia seeds
- Keep you full for longer
Chia seeds have several properties that can help us to feel full. The protein, healthy fat and fibre they contain all play a role here, as they slow down digestion. In addition, chia seeds form a gel when they come into contact with water, which increases their bulk and weight. To test this effect, researchers gave 15 participants a glucose drink on its own, or with 25g of ground chia seeds, or 31g of ground flax seeds. It was found that those given the chia had less desire to eat and a lower appetite score, even when compared with participants who had the flax seeds . This could be of benefit for appetite control and weight management. It also makes them a great choice as part of a healthy breakfast!
- Support digestion
Thanks to their high fibre content, chia seeds can be good for our digestion too. They contain soluble and insoluble fibre, which both play a role in keeping things moving along nicely!
- Improve cholesterol levels
Chia seeds and their oil could help to keep cholesterol and triglycerides (another type of blood fat) at healthy levels. An animal study by researchers at the University of Arizona found that feeding rats a diet containing whole or ground chia seeds resulted in reduction in triglycerides and an increase in HDL (‘good’) cholesterol . And a recent study by Brazilian researchers also found that rats fed a diet containing chia seeds or chia flour had lower LDL cholesterol, lower triglycerides and higher HDL cholesterol than those on a ‘control’ diet . However, there don’t yet seem to be good-quality human studies to prove this benefit.
- Improve blood sugar control
Animal studies also suggest that chia can help to reduce blood glucose levels and/or improve glucose tolerance (how quickly or how well the body processes glucose from carbohydrates in food) [7,8]. And a human study also showed similar benefits: in the study mentioned above, where participants took either ground chia or ground flax with a glucose drink (or just the drink alone), it was found that those taking the chia had a significantly reduced the rise in blood sugar after the glucose, even compared to individuals who had the flax seed too .
Improving blood sugar control has a multitude of benefits. It helps to prevent insulin resistance and diabetes. It also helps to balance energy levels, supports focus and concentration, helps regulate appetite and cravings, and even can even benefit our mood, sleep and hormone balance. The foundation for good blood sugar control is eating a wholefoods-based diet, limiting refined carbohydrates and processed foods, and ensuring adequate protein intake. But adding chia seeds could help further!
Chia could have anti-inflammatory benefits via its antioxidant content (as mentioned above). It could also help by increasing our blood levels of omega-3 EPA (eicosapentaenoic acid). In our body, EPA can be directly converted into anti-inflammatory substances. Our main source of EPA is oily fish; but our body can also make some EPA from omega-3 (ALA) such as that found in chia seeds. In fact, a study on ten women who took 25g of ground chia seeds per day for seven weeks showed a 30% increase in their blood levels of EPA over the study . This could be particularly good news for vegetarians and vegans or anyone who can’t eat fish or take fish oil, as a good way of getting their anti-inflammatory and heart-healthy EPA.
- A great food for vegans (and vegetarians)
Their ‘complete protein’ content is fantastic for vegans in particular, who can struggle to get an optimal amount of protein with the right amino acid ratios. And the calcium they contain provides an excellent alternative to dairy sources.
As a source of omega-3 alpha linolenic acid, chia seeds may help to protect the liver as well as the heart. In a study on rats fed a high-carbohydrate, high-fat diet, those given 5% chia seeds showed reduced fatty build-up in their liver, and reduced liver inflammation and scarring . Again, this hasn’t been replicated in humans, but it suggests that including chia seeds could be beneficial.
So now you know about their benefits, why not make yourself a tasty chia seed pudding for breakfast tomorrow?
- Imran M et al. Fatty acids characterization, oxidative perspectives and consumer acceptability of oil extracted from pre-treated chia (Salvia hispanica L.) seeds. Lipids Health Dis. 2016 Sep 20;15(1):162.
- Nutritiondata.self.com. (2017). Seeds, chia seeds, dried Nutrition Facts & Calories. [online] Available at: http://nutritiondata.self.com/facts/nut-and-seed-products/3061/2 [Accessed 10 Jan. 2017].
- Reyes-Caudillo, E et al. Dietary fibre content and antioxidant activity of phenolic compounds present in Mexican chia (Salvia hispanica L.) seeds. Food Chemistry 2008;107(2):656-663.
- Superfoodly.com. (2017). ORAC Values: 2017 Food Antioxidant Database | Superfoodly. [online] Available at: https://www.superfoodly.com/orac-values/ [Accessed 10 Jan. 2017].
- Vuksan V et al. Comparison of flax (Linum usitatissimum) and Salba-chia (Salvia hispanica L.) seeds on postprandial glycemia and satiety in healthy individuals: a randomized, controlled, crossover study. Eur J Clin Nutr. 2016 Dec 21.
- Ayerza R Jr, Coates W. Effect of dietary alpha-linolenic fatty acid derived from chia when fed as ground seed, whole seed and oil on lipid content and fatty acid composition of rat plasma. Ann Nutr Metab. 2007;51(1):27-34.
- da Silva BP et al. Chia Seed Shows Good Protein Quality, Hypoglycemic Effect and Improves the Lipid Profile and Liver and Intestinal Morphology of Wistar Rats. Plant Foods Hum Nutr. 2016 Sep;71(3):225-30.
- Marineli Rda S et al. Chia (Salvia hispanica L.) enhances HSP, PGC-1α expressions and improves glucose olerance in diet-induced obese rats. Nutrition. 2015 May;31(5):740-8.
- Jin F et al. Supplementation of milled chia seeds increases plasma ALA and EPA in postmenopausal women. Plant Foods Hum Nutr. 2012 Jun;67(2):105-10.
- Poudyal H et al. Lipid redistribution by α-linolenic acid-rich chia seed inhibits stearoyl-CoA desaturase-1 and induces cardiac and hepatic protection in diet-induced obese rats. J Nutr Biochem. 2012 Feb;23(2):153-62.