Short answer: bulgur has the fewest calories (83 per 100g cooked) and the most fiber (4.5g) of the common grains. Buckwheat is the pick if you need gluten-free. Couscous — surprise — isn't a whole grain at all. They all look like interchangeable beige carbs in the bulk aisle, but per 100g cooked they span a 40-calorie range and a 5x fiber range. Here are the numbers, then what to actually do with them.
The Numbers: 7 Grains Per 100g, Cooked
All values below are for 100g cooked (USDA data) — that's the only fair way to compare, because grains absorb different amounts of water. Sorted by calories:
| Grain (100g cooked) | Calories | Protein | Carbs | Fiber |
|---|---|---|---|---|
| Bulgur | 83 | 3.1g | 18.6g | 4.5g |
| Buckwheat | 92 | 3.4g | 19.9g | 2.7g |
| Couscous | 112 | 3.8g | 23.2g | 1.4g |
| Millet | 119 | 3.5g | 23.7g | 1.3g |
| Quinoa | 120 | 4.4g | 21.3g | 2.8g |
| Barley (pearled) | 123 | 2.3g | 28.2g | 3.8g |
| White rice | 123 | 2.9g | 26.0g | 0.9g |
Where are oats? Oats are usually listed dry (379 calories, 13.2g protein, 10.1g fiber per 100g), which makes them look like a superfood next to cooked grains. Cooked into porridge they absorb roughly 2-3x their weight in water, so a 100g cooked serving lands in the same range as the grains above. Any comparison that puts dry oats against cooked rice is lying to you with units — we've broken it down properly in buckwheat vs oats and bulgur vs oats.
Bulgur vs Buckwheat: Not the Same Thing
These two get confused constantly, and they shouldn't — they're not even related. Bulgur is cracked, par-cooked wheat. Buckwheat isn't wheat at all — despite the name, it's a seed (a "pseudocereal," like quinoa) and completely gluten-free.
Nutritionally they're close: 83 vs 92 calories, 3.1g vs 3.4g protein. The real differences are the ones that decide for you:
- Gluten: bulgur has it, buckwheat doesn't. If you're celiac or gluten-sensitive, the debate is over.
- Fiber: bulgur wins clearly — 4.5g vs 2.7g per 100g. That's the difference you feel at 4pm.
- Cooking: fine bulgur just needs a soak in hot water; buckwheat groats want 15 minutes of simmering and can go mushy if you look away.
Full head-to-head numbers: buckwheat vs bulgur.
Cutting Calories? Bulgur and Barley Do the Most Work
For weight loss, the metric that matters isn't calories alone — it's fiber per calorie, because fiber is what keeps you full after the plate is empty. Bulgur delivers 4.5g of fiber for 83 calories. White rice gives you 0.9g for 123. Same beige pile on the plate, five times the staying power.
Barley is the sleeper here: 3.8g fiber, and most of it is beta-glucan — the soluble kind that turns to gel in your stomach and slows everything down. It has more calories than bulgur (123 vs 83), but it eats like a much bigger meal. See barley vs bulgur and barley vs couscous for the direct matchups, or the bigger picture in best foods for weight loss.
Protein? Quinoa Leads the Cooked Pack
At 4.4g per 100g cooked, quinoa tops this list, and it's a complete protein (all nine essential amino acids) — rare for a plant. But keep it honest: no grain is a protein source. They're carb sources with a protein bonus. A chicken breast has ~31g per 100g; the "high-protein grain" marketing is comparing crumbs. Build meals where grains do the carb job and something else does the protein job — that's the whole trick of counting macros without going insane.
Gluten-Free? Buckwheat and Millet Are Your Grains
Of the seven in the table, only three are gluten-free: buckwheat, millet, and quinoa. Buckwheat brings the most fiber of the three (2.7g); millet is the mildest-tasting and the cheapest. They're closer nutritionally than the internet suggests — the real differences are texture and price. Numbers side by side: buckwheat vs millet. And if you're swapping millet in for couscous to go gluten-free, the trade is almost calorie-neutral: couscous vs millet.
Couscous Is Technically Pasta
This surprises people every time: couscous isn't a grain. It's tiny balls of semolina flour and water — the same ingredients as spaghetti. That's why its fiber is so low (1.4g) despite the health-food-aisle placement. It cooks in five minutes and there's nothing wrong with it, but you should know you're choosing pasta with better marketing. The comparisons back this up: couscous vs pasta and couscous vs white rice.
So Which One Should You Buy?
- Losing weight: bulgur. Fewest calories, most fiber, zero effort to cook.
- Gluten-free: buckwheat first, millet if you want milder and cheaper.
- Most protein per calorie: quinoa — and it's complete protein.
- Soups and stews: barley. The beta-glucan texture is the point.
- Five minutes to dinner: couscous — just know it's pasta wearing a costume.
The honest summary: any of these beats white rice on fiber, none of them will make or break your diet, and the best grain is the one you 'll actually cook on a Tuesday. What decides your results is the total on the plate — if you want that handled automatically, take the free quiz and Sunn will track it with you on WhatsApp.
Written by Espen Opdahl
Founder of Sunn. Building AI-powered nutrition coaching to make healthy eating simple. Nutrition data sourced from the USDA FoodData Central database.
Medical disclaimer: This content is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making changes to your diet or exercise routine.