Chia Seeds: Nutritional Profile and What They Actually Contain
Updated:
Chia seeds have one of the more straightforward nutritional cases to make in the whole foods category. The composition is genuinely interesting, the data is well established, and you do not need to reach for dramatic claims to describe them accurately. This post covers what chia seeds actually contain, what that means practically, and how to think about them as part of a varied diet.
What chia seeds contain
The nutritional values below are based on a 28g serving (roughly two tablespoons), sourced from our supplier’s technical data specification. Chia seeds are an agricultural product and composition varies slightly by batch, season and growing conditions.
| Nutrient | Per 28g serving | % Reference intake |
|---|---|---|
| Energy | 120 kcal / 503 kJ | 6% |
| Protein | 5.9g | 12% |
| Fat | 8.1g | 12% |
| of which omega-3 (ALA) | 4.2g | — |
| Carbohydrate | 0.8g | <1% |
| of which sugars | 0.2g | <1% |
| Fibre | 10.1g | — |
| Calcium | 156mg | 20% |
| Magnesium | 85mg | 23% |
| Phosphorus | 195mg | 28% |
| Iron | 2.1mg | 15% |
Reference intakes based on an average adult diet of 2,000 kcal per day.
What stands out about the profile
Omega-3 (ALA) — A 28g serving provides around 4g of alpha-linolenic acid, the plant-based form of omega-3. Chia seeds are one of the richest plant sources of ALA available. It is worth being specific about the form: ALA is not the same as the long-chain omega-3s (EPA and DHA) found in oily fish. The body converts ALA into EPA and DHA, but conversion rates are relatively low. For people who do not eat fish, chia seeds are a useful dietary source of ALA, but algae-based supplements are the only plant-based source of EPA and DHA directly.
Fibre — The fibre content is one of chia’s most notable qualities. A 28g serving provides around 10g of fibre — roughly a third of the recommended daily intake. The fibre is a mix of soluble and insoluble. The soluble fibre is what creates the gel when chia seeds are soaked in liquid.
Calcium — A 28g serving provides around 20% of the daily reference intake for calcium, which is notable for a seed.
Protein — Around 6g per serving, with all essential amino acids present. Chia is not a primary protein source in the way that legumes or animal products are, but it contributes meaningfully to protein intake in a mixed diet. At approximately 21% protein by dry weight, it is higher in protein than most cereals.
Carbohydrate — The net carbohydrate content is very low at under 3g per 100g. Most of the seed’s bulk is accounted for by fibre and fat rather than available carbohydrates.
Antioxidants — Chia seeds contain flavonoids, phenolic acids and other plant compounds. These are what protect the seeds’ omega-3 from oxidising — allowing whole chia seeds to be stored for considerably longer than ground flax without going rancid.
What chia seeds are not
Worth being clear about a few things that circulate regularly but overstate the case. Chia seeds are not a complete protein substitute for animal products. They are not a meaningful source of vitamin B12. Their omega-3 (ALA) cannot directly replace the EPA and DHA that oily fish provides. They are nutritionally useful within a varied diet — not a replacement for dietary variety.
Organic certification — why it matters for seeds
Conventionally grown chia seeds can carry pesticide residues on the seed surface. Because chia is eaten whole and the seed is small relative to its surface area, pesticide load matters more than it might for a product where you remove an outer layer before eating. Organic certification addresses this directly.
Our organic chia seeds are sourced from South America and are Soil Association certified organic — the same standard we apply across our whole range. For practical ideas on how to use chia seeds at home, our post on how to eat chia seeds covers everyday preparation in detail.
