5 foods under 30 calories per 100 g
At under 30 kcal per 100 g the food finally starts carrying something besides water. The band below is salad and very little else. This one has protein in single grams, real fibre, and vegetables that stand up to being cooked and eaten as the main thing on the plate.
| Food | kcal per 100 g | Protein | Fibre |
|---|---|---|---|
| White mushrooms | ~22 | 3.1 g | 1.0 g |
| Spinach, raw | ~23 | 2.9 g | 2.2 g |
| Cauliflower | ~25 | 1.9 g | 2.0 g |
| Cabbage | ~25 | 1.3 g | 2.5 g |
| Aubergine (eggplant) | ~25 | 1.0 g | 3.0 g |
Also on this rung: asparagus (20), rocket (25), pumpkin (26), turnip (28) and watermelon, which sits exactly on 30.
Mushrooms are the outlier worth knowing about — 3.1 g of protein per 100 g is more than any vegetable in the two bands below, and UV-exposed mushrooms are one of the only non-animal foods with meaningful vitamin D.
The cook-down trap
Here is what separates this band from the one beneath it in practice: these foods shrink.
Five hundred grams of raw spinach wilts to about 100 g. The calories do not change — it is 115 kcal either way — but the volume collapses, and volume was the entire point. If you are eating spinach for fullness, a pan of it will not do the job that a bowl of it would.
The same holds, less dramatically, for cabbage and mushrooms. Mushrooms are roughly 90 per cent water and lose a third of their weight in a hot pan.
The practical answer is to split it: some raw for bulk, some cooked for the meal. A bowl of raw spinach under a hot topping does both at once.
What you cook them in costs more than they do
This is the number that matters in this band, and it is not close.
| Dish | Calories |
|---|---|
| 300 g mushrooms, dry-fried | ~66 kcal |
| 300 g mushrooms, 1 tbsp butter | ~168 kcal |
| 300 g mushrooms, 2 tbsp butter and a splash of cream | ~290 kcal |
| 200 g aubergine, roasted with 1 tsp oil | ~90 kcal |
| 200 g aubergine, fried | 250–350 kcal |
Aubergine is the worst offender on any vegetable list, because it is structurally a sponge. A hundred grams of fried aubergine can hold 10 to 15 g of oil — 90 to 135 kcal of fat sitting inside a 25 kcal vegetable. Salting and pressing it first, or roasting with a sprayed teaspoon rather than a poured tablespoon, is a 90 kcal difference on an identical dish.
The vegetable is never the thing to economise on. The fat is.
Cauliflower rice, honestly
The swap people ask about: 100 g of cauliflower rice is 25 kcal against 130 for 100 g of cooked white rice. A 200 g portion saves about 210 kcal, which is a real number and repeats every time you cook.
What is true about it: the texture holds up better than most substitutions in this band, it takes sauce, and it browns.
What is not: it is not rice. It is wetter, it has a faint brassica smell, and it does not give the starchy, settling fullness that rice does — because that fullness came from the starch. Most people who keep the habit mix the two half and half, which still takes 100 kcal off the plate and tastes like a rice dish. Cauliflower’s own page has the portion figures.
Where this band sits
This is the most useful rung for cooking from, because it is the first one where the vegetable can be the dish. Below 20 kcal you are assembling salads; here you can roast a tray, build a soup, or fill half a plate with something that has been in a pan.
The limit is unchanged from the bands below: 25 kcal per 100 g means a 2,000 kcal day would be eight kilos of food. Nobody is running a diet out of this band. It is the half of the plate that costs nothing, so the other half can be chosen on other grounds — and the next rung up is where nutrition proper starts to arrive.
The rest of the ladder
Under 5 · under 10 · under 20 · under 30 · under 50 · under 100 · under 200 · under 300 · under 400 · under 500
Figures are typical values from USDA FoodData Central and product labels, and vary by variety, size and preparation. General information, not medical advice.