What are chia seeds?
From the standpoint of a botanist, chia is the ungerminated unit of life produced from the flower of the Salvia hispanica plant, which is a type of sage native to South and Central America. From the standpoint of a nutritionist, chia seeds are an incredible tiny package teeming with phenomenal amounts of immune system boosting essential fatty acids, intestine-soothing fibre, bone-strengthening minerals, and skin healing vitamins.
Chia seeds were a staple food for the Aztec civilization. Together with corn, beans, and amaranth, chia seeds were among the main crops cultivated for nourishment and for use in religious ceremonies. They were an important food precisely because they're substantial and easy to grow—they're resistant to drought, extreme climate and soil conditions, and most insect pests. This is also relevant today because the leaf essential oil acts as a powerful insect repellant and therefore the crop can be grown without pesticides.
Chia Seeds as an Anti-Inflammatory Superfood
Recently, chia seeds have been touted as a superfood, and it's easy to understand why. They're an excellent source of the anti-inflammatory essential omega-3 fat known as alpha-linolenic acid (abbreviated as ALA or LNA). This is the feature that has thrust them in the limelight of the health-conscious. Chia seeds could therefore be considered therapeutic food because they can help prevent and remedy deficiencies of essential fatty acids.
Chia seeds are rivalled only by flax seeds and perilla seeds as a top plant source of omega-3 fats that are commercially available and abundant. (Kiwi seeds are also high in ALA, but the whole seed and the extracted oil aren't yet sold commercially.) Interestingly, the name chia means "oily" in the Aztec language.
Not only are chia seeds rich in ALA, serving up to 20 g or more of this omega-3 per 100 g of seed, they're also a source of the essential omega-6 fat, linoleic acid (abbreviated as LA). The omega-3 to omega-6 ratio is 1:3 in chia, which means chia seeds are powerfully anti-inflammatory. I'll explain the importance of the omega-3 to omega-6 ratio in a future blog.
To add more oomph to their anti-inflammatory properties, chia seeds are also excellent sources of allergy-staving phenol antioxidants such as quercetin, kaempherol, chlorogenic acid, caffeic acid, and myricetin. These phenols benefit the body in many ways, but particularly interesting is the ability of quercetin and kaempherol to stabilize mast cells.
Mast cells are a type of immune cell involved in allergic reactions. When an allergen triggers the immune system, mast cells release histamine, bradykinin, heparin, and other mediators that help elicit an immune system allergic response. These mediators are known as cytokines—which literally translates to "cell movement". Cytokines are messenger substances that once released from a cell, elicit a reaction—such as physical movement, known as chemotaxis, or biochemical activity—from other local or regional cells.
Histamine and bradykinin increase the permeability of the vascular system, cause runny nose and itchy eyes, contribute to inflammatory swelling and pain, effect drowsiness, and contribute to many symptoms associated with allergies. Quercetin and kaempherol help to stabilize mast cells so that they don't release these allergy-responsive cytokines.
Phenols also act as antioxidants, which have innumerable roles in the body. For example, they can help protect LDL cholesterol from oxidation.This particularly benefits the cardiovascular system. In fact, chia seeds are a fantastic food for protecting the cardiovascular system because of they also have an ideal omega-3 to omega-6 fat ratio, are extremely low in saturated fats, contain no simple carbohydrates, and are extremely high in fibre—providing 20 to 40 % fibre dry weight (which accounts for 80 to 115% of the daily recommended intake, respectively!).
One type of water soluble fibre found in chia seed is quite interesting. It's similar to the fibre found in flax seeds in that it's a mucilaginous polysaccharide. It can absorb up to 12 times its dry weight in water! This is a highly beneficial property because as it swells, it also:
-binds toxins in the intestines, helps lower blood lipids and blood sugar (which can help lower the risk of inflammatory metabolic diseases such as insulin resistance, diabetes and obesity)
- flushes bile acids out with the stool
- soothes irritated or inflamed intestinal tissues
- increases and sustains satiety, thereby helping you feel full quickly and for extended periods of time
- reduces cravings, especially for sweet tastes and refined carbohydrates (and you'll see the evidence of that in your shrinking waistline!).
Note: It's essential that you drink enough water (warm is best) or herbal tea after you've eaten chia seeds or pre-soak them prior to eating them so you avoid uncomfortably distending your gastrointestinal tract. Too much fibre without enough hydration can cause a lot of tummy swelling and discomfort!
Chia Seed as a Nutrient Powerhouse
Chia seeds are also a good source of calcium, potassium, and magnesium—minerals that strengthen bones and prevent acidifying diets from deteriorating this important organ. In addition, they provide healthy amounts of iron, selenium, and zinc. You'll also receive a healthy dose of vitamins B1, B2, B3, and folic acid, all of which support the nervous system, plus vitamin A, which helps to keep skin healthy.
Similar to other seeds, chia is a good source of amino acids, including those that are essential. They contain up to 26 % by dry weight of protein (or 7.3 g protein per 28 g serving of whole seed—about 15% of the daily recommended intake of this macronutrient). That's as much protein as you'd get from an equivalent serving of raw walnuts or almonds! Chia is part of the Mint family (Labiatae or Lamiaceae) and therefore is free of gluten and gliadin proteins.
Chia seeds range in colour from dark grey-black to light brown to beige or pale white. However, to quote the late and great Michael Jackson, "it don't matter if you're black or white"—chia of all colours are equally nutritious! Some cultivars do produce more omega-3s while others contain more amino acids, but overall they're quite comparable. As with any other plant, their mineral, vitamin, and phytonutrient content varies with the geographical location (i.e., soil, elevation, etc.), climate, season, and other environmental factors such as degree of herbivory, pollination, pathogenic stress, and/or competition.
How Can You Add Chia Seeds to your Diet?
This is the tasty part! How can you incorporate these wonderful little seeds into your diet? Chia seeds have a mild flavour, so it's easy to add them to a wide range of dishes. They taste similar to de-fatted macadamia nuts. The true distinction that chia offers recipes is texture.
Chia fibre thickens and gels foods together, so chia seeds are a superb addition to any smoothie, breakfast cereal, porridge, salad dressing, sauce, gravy, soup, broth, pudding, yogurt, spread, raw jam, or chutney. Chia seeds are best eaten raw to protect the anti-inflammatory omega-3 and omega-6 fats from becoming oxidized. I suggest you toss them onto cooked foods after the food has been removed from heat. For example, serve up a bowl of hot porridge or soup and then wait until the meal is cool enough to eat before you add the chia seeds.
However, it is possible to use chia seeds in some cooking and baking. Chia seed fibre actually makes a great binding and thickening agent, and the seeds make a great substitute for common allergens such as gluten grain flour, egg, nuts, and corn starch.So how do you benefit from using chia seed mucilage without damaging the anti-inflammatory oils? Studies have shown that the best way to protect the oils is to:
- Use whole chia seeds as much as possible.
- If you use ground chia seeds, grind them yourself. This ensures the oils are as fresh as possible and it decreases the amount of endogenous seed antioxidants that are consumed to protect oils from oxidation.
- Use coarsely ground chia seeds to increase the amount of oils that are protected by the seed coat.
- Use as much moisture in the recipe as possible. Water helps prevent cooked food from reaching extremely high temperatures, and the higher the temperature of the food, the more damage omega oils in the chia seeds will have to endure.
- Don't heat chia seeds on their own. Always make sure they're combined with other ingredients.
- Avoid extremely high temperatures (for example, don't use the broiler setting on your oven to bake anything containing chia seeds).
- Add as many antioxidant rich spices (such as cinnamon bark and ginger root), herbs (such as basil and thyme), and foods (such as fruits) to cooking and baking to further protect the oils from oxidation.
These suggestions don't hold true for chia seed oil. Chia seed oil has less physical and antioxidant protection than the fats in the whole seed that are relatively protected from oxidation caused in the presence of heat, oxygen, moisture, and/or light. When still intact in the whole seed kernel, the sensitive polyunsaturated fats are nestled within the thick seed coat, which offers physical protection, and they're enmeshed with antioxidants such as vitamin E that prevent oxidation. Oxidized omega oils are pro-inflammatory. I'll explain why and how in a future blog.
It's the vitarock seed week! I'll be writing a series on seed superfoods: chia today and flax (part 1) tomorrow, followed by flax seed again (part 2!), hemp, and pumpkin seeds!
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