Is Flaxseed Keto Friendly? Carbs, Nutrition and Baking Uses
Is flaxseed keto friendly? Yes. Flaxseed, sold in the UK as linseed, is mostly fat and fibre. Per 100g it has about 1.6g carbohydrate as UK labels count it, with fibre listed separately. A level tablespoon of milled flaxseed (about 7g) has roughly 0.1g carbohydrate, so it fits easily into a 20g daily carb limit. Use it milled for binding and whole for crunch.
At a glance
- 1.6gcarbohydrate per 100g, fibre excluded (USDA)
- 0.1gcarbohydrate in 1 tbsp milled flaxseed (7g)
- 27.3gfibre per 100g (USDA)
- 1 + 31 tbsp milled flaxseed + 3 tbsp water = 1 flax egg
On this page
Flaxseed turns up in a lot of low-carb recipes, from seeded crackers to flax eggs and quick breads. If you're following a keto diet, the first question is simple: how many carbs does it have, and how do you count them on a UK label?
This guide covers what flaxseed is, its nutrition per 100g and per tablespoon, how net carbs work for flaxseed on UK and US labels, how it compares with other seeds, and how to use it in keto baking and everyday meals.
Is flaxseed keto friendly?
Yes. A keto diet usually keeps carbohydrate to around 20 to 50g a day, and flaxseed has very little of it once the fibre is taken out. USDA FoodData Central lists 28.88g of total carbohydrate per 100g of flaxseed, and 27.3g of that is fibre. That leaves about 1.6g of carbohydrate per 100g, the way a UK label counts it.
In practice you'll use flaxseed a spoonful or two at a time, so the carbs are tiny:
- 1 level tablespoon of milled flaxseed (7g): about 0.1g carbohydrate.
- 1 level tablespoon of whole flaxseed (10.3g): about 0.2g carbohydrate.
- A 30g portion: about 0.5g carbohydrate.
Flaxseed is also mostly fat (about 42g per 100g), which suits the high-fat, low-carb pattern of keto. It's energy-dense, though, at 534 kcal per 100g, much the same as nuts. If you're new to keto, our guide to what ketones are explains the basics.
What is flaxseed?
Flaxseed is the seed of the flax plant (Linum usitatissimum), one of the oldest cultivated crops. Its stems give the fibre that's spun into linen, and its small, glossy seeds are eaten whole or ground. In the UK the seeds are usually sold as linseed, while US and Canadian recipes call them flaxseed. They're the same seed: see our guide Is linseed the same as flaxseed? for the full rundown of names and forms.
- Whole flaxseed (linseed): brown or golden seeds that keep their shape when baked.
- Milled flaxseed: the whole seed ground to a coarse powder, also called flax meal, ground flaxseed or milled linseed.
- Golden vs brown: the same species. Golden has a milder taste and suits pale bakes; brown is darker and earthier.
- Flaxseed oil: the cold-pressed oil for food. It has no carbohydrate but none of the seed's fibre either.
Flaxseed nutrition per 100g and per tablespoon
The UK's CoFID dataset doesn't have an entry for flaxseed or linseed, so we've used the USDA FoodData Central entry "Seeds, flaxseed" (FDC ID 169414). We've set the figures out the way a UK nutrition label does, with fibre listed separately from carbohydrate.
| Nutrient | Per 100g | Per tbsp milled (7g) |
|---|---|---|
| Energy | 534 kcal | 37 kcal |
| Fat | 42.2g | 3.0g |
| of which saturates | 3.7g | 0.3g |
| Carbohydrate | 1.6g | 0.1g |
| of which sugars | 1.6g | 0.1g |
| Fibre | 27.3g | 1.9g |
| Protein | 18.3g | 1.3g |
| Salt | 0.08g | 0.01g |
Source: USDA FoodData Central, SR Legacy, "Seeds, flaxseed" (FDC ID 169414), checked 25 October 2026. Carbohydrate is total carbohydrate (28.88g) minus fibre (27.3g), as on UK labels. Salt is sodium (30mg per 100g) × 2.5. The 7g tablespoon is USDA's portion weight for ground flaxseed; weigh your own if you can. Per-tablespoon figures are our own calculations.
Almost all of the small carbohydrate figure is sugars, mainly sucrose. Most of the fat is polyunsaturated (28.7g per 100g), with 7.5g monounsaturated and 3.7g saturated. Whole flaxseed has the same nutrition per 100g as milled; a level tablespoon of whole seeds just weighs more, about 10.3g.
Net carbs in flaxseed and UK labels
What are net carbs? Net carbs are carbohydrate minus fibre, and some people also subtract polyols such as erythritol. The term comes from American labels, where fibre is counted inside "Total Carbohydrate", so keto followers subtract it to get net carbs.
UK labels work differently. Fibre is listed on its own line and isn't included in the carbohydrate figure, so the carbohydrate on a UK pack already works like a net carbs number. Don't subtract the fibre a second time.
| Per 100g flaxseed | US-style label | UK-style label |
|---|---|---|
| Carbohydrate shown | 28.9g | 1.6g |
| Fibre | 27.3g | 27.3g |
| Fibre inside carbs? | Yes | No |
| Net carbs | 1.6g | 1.6g |
USDA FoodData Central figures (FDC ID 169414). Individual packs vary, so check the label on the bag you buy.
If a UK bag of linseed shows a carbohydrate figure of a few grams per 100g and a fibre figure of 20g or more, that carbohydrate figure is the one to count. A figure close to 29g usually means you're looking at US-style figures with fibre included. Our guide to net carbs on UK food labels explains this step by step.
Flaxseed vs other seeds: carbs compared
Flaxseed has the lowest carbohydrate figure of the common baking seeds, once fibre is taken out. All figures below are per 100g from the same USDA dataset, shown the UK way.
| Seed (per 100g) | Carbs | Fibre |
|---|---|---|
| Flaxseed (linseed) | 1.6g | 27.3g |
| Pumpkin seeds | 4.7g | 6.0g |
| Chia seeds | 7.7g | 34.4g |
| Sunflower seeds | 11.4g | 8.6g |
| Sesame seeds | 11.7g | 11.8g |
Source: USDA FoodData Central, SR Legacy: flaxseed (169414), pumpkin and squash seed kernels, dried (170556), chia seeds, dried (170554), sunflower seed kernels, dried (170562), sesame seeds, whole, dried (170150). Carbohydrate is total carbohydrate minus fibre. Checked 25 October 2026.
How to use flaxseed in keto baking
Flaxseed has no gluten-forming proteins and very little starch, so it can't replace wheat flour on its own. What it does well is bind ingredients, add body and give crunch. Whether you use it whole or milled makes the biggest difference.
Milled flaxseed: binding and moisture
Grinding breaks the seed coat, so milled flaxseed soaks up liquid and turns thick and slightly gel-like. That makes it a handy binder in muffins, cookies, pancakes and flatbreads. You can buy it milled or grind whole seeds yourself in a clean, dry spice or coffee grinder.
Whole flaxseed: crunch and texture
Whole seeds keep their shape, so they add crunch to crackers and a seeded finish to loaves. Our keto seed crackers use 60g of whole golden linseed with sunflower, pumpkin and sesame seeds, held together with psyllium husk powder and oat fibre.
How to make a flax egg
A flax egg replaces one egg in many bakes. King Arthur Baking's method:
- Stir 1 tablespoon of milled flaxseed (milled linseed) into 3 tablespoons (42g) of water.
- Leave it for 5 to 10 minutes, until thick and gelatinous.
- Use it in place of one egg.
Flax eggs bind but don't trap air the way eggs do, so King Arthur recommends them for cookies, quick breads, muffins, brownies and bars rather than light sponges. In keto baking, where eggs often do much of the structural work, use flax eggs to replace one or two eggs rather than all of them.
Flaxseed, psyllium husk and oat fibre
Flaxseed, psyllium husk and oat fibre are often used together in low-carb baking, but they do different jobs. Our Psyllium Husk Powder forms a much stronger gel, which gives a loaf like our keto bread recipe its bread-like crumb. Our Oat Fibre adds bulk and a lighter texture. Milled flaxseed gives a softer, denser result and adds fat and flavour. Stick to the binder a recipe was written for, or test a small batch if you swap. For more low-carb flours side by side, see our guide to keto flour.
Flaxseed in our mixes
Our Scone Mix and Cookie Mix both include golden linseed in their ingredients lists. The Scone Mix is made with almond flour, erythritol, coconut flour, whey protein and golden linseed; you add butter, an egg and Greek yoghurt.
The Scone Mix and Cookie Mix both contain almonds (tree nuts), and the Scone Mix also contains milk (whey protein). Always check the pack for full allergen information.
We offer free delivery on orders over £30.
Easy ways to add flaxseed to keto meals
Flaxseed has a mild, nutty taste, so it's easy to add to food you already eat. A spoonful at a time is the usual amount.
- Porridge: stir a spoonful of milled flaxseed into a bowl of keto porridge. Our guide Is porridge keto? explains why oat porridge is a different story.
- Yoghurt and smoothies: sprinkle milled flaxseed over full-fat Greek yoghurt with berries, or blend it into a low-carb smoothie to thicken it.
- Crumb coatings: mix milled flaxseed with ground almonds and grated Parmesan to coat chicken or fish instead of breadcrumbs.
- Toppings: scatter whole seeds over salads, seeded loaves and crackers before baking.
- Bakes: swap a little of the almond flour in muffins or pancakes for milled flaxseed, or use a flax egg.
For more ideas, browse our keto recipes, or add a bag of linseed to your list from our keto shopping list for beginners.
How to store flaxseed
Flaxseed is about 42% fat, and once the seed coat is broken that fat can turn rancid, giving a bitter, paint-like smell. Keep whole seeds in an airtight container in a cool, dry, dark cupboard. Keep milled flaxseed in an airtight container in the fridge, or freeze it for longer; it stays free-flowing, so you can spoon it straight from the freezer. If milled flaxseed smells sharp or bitter rather than mild and nutty, throw it away.
Frequently asked questions
Is ground flaxseed keto friendly?
Yes. Ground flaxseed, sold in the UK as milled linseed, is the whole seed ground, so it has the same nutrition per 100g. A level tablespoon, about 7g, has roughly 0.1g of carbohydrate and 1.9g of fibre, using USDA FoodData Central figures. It's the form to use for binding, flax eggs and low-carb bakes.
Does flaxseed have carbs?
Yes, but very few once the fibre is taken out. USDA lists 28.88g of total carbohydrate per 100g of flaxseed, and 27.3g of that is fibre. On a UK-style label, which lists fibre separately, that leaves about 1.6g of carbohydrate per 100g. A US-style label shows the higher total figure instead.
What are net carbs?
Net carbs are carbohydrate minus fibre, and some people also subtract polyols such as erythritol. The term comes from US labels, which include fibre in total carbohydrate. UK labels already list fibre separately, so the carbohydrate figure on a UK pack works like a net carbs number, and you don't subtract the fibre again.
Is flaxseed lower in carbs than chia seeds?
Yes. Using USDA FoodData Central figures with the fibre taken out, flaxseed has about 1.6g of carbohydrate per 100g and dried chia seeds about 7.7g. Both are mostly fat and fibre. Chia seeds soak up liquid and set into a gel whole, while flaxseed binds best once it has been milled.
How do you make a flax egg?
Stir 1 tablespoon of milled flaxseed into 3 tablespoons of water and leave it for 5 to 10 minutes, until thick. That replaces one egg in cookies, muffins, quick breads, brownies and bars. Flax eggs bind but don't trap air, so they suit denser bakes better than light, fluffy sponges.
Sources
- US Department of Agriculture. FoodData Central: SR Legacy, "Seeds, flaxseed", FDC ID 169414 (total carbohydrate 28.88g, fibre 27.3g, sugars 1.55g, fat 42.16g, saturates 3.663g, protein 18.29g, sodium 30mg, 534 kcal per 100g; portion weights 7g per tablespoon ground and 10.3g per tablespoon whole). Seed comparison: FDC IDs 170554, 170556, 170562 and 170150. Checked 25 October 2026. UK-style carbohydrate, salt and per-portion figures are our own calculations. CoFID 2021 has no linseed entry.
- King Arthur Baking. No eggs? Here's your guide for substituting (flax egg method and best uses).
- Groovy Keto product pages: Psyllium Husk Powder, Oat Fibre, Scone Mix and Cookie Mix: ingredients lists, allergen information and pack sizes.
