How many calories are in spinach?
A 100 g bag of raw spinach — two generous bowls of leaves — is about 23 kcal. A single cup of raw spinach is nearer 7. Nothing else on a dinner plate gives that much bulk for that little energy, and nothing carries so much mythology.
Per portion
| Portion | Calories | Protein | Carbs | Fat |
|---|---|---|---|---|
| 1 cup raw leaves (30 g) | ~7 kcal | 0.9 g | 1.1 g | 0.1 g |
| 100 g raw | ~23 kcal | 2.9 g | 3.6 g | 0.4 g |
| 250 g bag, raw | ~58 kcal | 7 g | 9 g | 1 g |
| 1 cup cooked, drained (180 g) | ~41 kcal | 5.3 g | 6.8 g | 0.5 g |
| 100 g sautéed in 1 tsp oil | ~65 kcal | 2.9 g | 3.6 g | 5 g |
| 150 g creamed spinach | ~220 kcal | 5 g | 8 g | 18 g |
| 200 g palak paneer | 250–350 kcal | 12 g | 10 g | 22 g |
What changes the number
“A bowl of spinach” means two different things. Raw leaves are mostly air between them. Cooking collapses that structure, so a cup of cooked spinach holds roughly six times the leaf of a cup of raw — 41 kcal against 7, for the same word. Per 100 g the two are almost identical, because the water that leaves is weighed, not burned. Estimate by weight before cooking.
Oil, which spinach takes up readily. A tablespoon of oil is about 120 kcal and 200 g of raw spinach is about 46, so sautéing it — usually after a base of onion — more than triples a dish whose vegetable barely registers.
Cream and paneer. Creamed spinach runs near 150 kcal per 100 g; palak paneer is 125–175 per 100 g depending on how much cream, ghee and cheese went in. These are good foods and they are not spinach dishes in any calorie sense: the leaf contributes perhaps 20 kcal of a 300 kcal serving.
Frozen and smoothies. Frozen spinach is already wilted, so a 100 g block stands in for several raw bowls at the same energy. Fifty grams in a smoothie adds about 12 kcal; whatever else is in the glass is the actual number.
Where it fits in a deficit
The best volume-per-calorie trade available, and useful as filler in almost anything: a 250 g bag wilted into a curry adds visible food for under 60 kcal. That is the mechanism behind the whole high-volume approach and one of the easiest ways to make a calorie deficit feel less thin.
Protein per calorie is unusually good for a vegetable — about 12 g per 100 kcal — but the absolute amount is tiny. A whole kilogram of raw leaf carries under 30 g, roughly one chicken breast’s worth, so spinach supplements rather than supplies protein. Water-based fullness also empties within an hour or two; broccoli, with more fibre and more to chew, holds longer for not many more calories.
The iron myth, and oxalates
Spinach’s iron content was overstated by roughly a factor of ten in reference figures that circulated for most of the twentieth century, which is where Popeye’s forearms came from. The tidy explanation — a misplaced decimal point in a nineteenth-century analysis — is itself probably folklore. The error was real; the anecdote about its cause may not be.
The actual figure is a little under 3 mg per 100 g raw. Respectable for a vegetable, unexceptional overall, and a 100 g bag is only 100 g.
Spinach is also high in oxalic acid, which binds iron and calcium in the gut and reduces absorption of both — so even that modest iron is poorly taken up. Vitamin C alongside helps. Boiling and discarding the water removes a useful share of the oxalate, one of the few cases where tipping the cooking water away is right. Anyone prone to calcium-oxalate kidney stones is usually advised to moderate spinach, which is a conversation for a doctor rather than a calorie page. For everyone else the reading is simple: excellent food at a very low cost, just not the iron tablet it was sold as.
Figures are typical values and vary by variety, size and preparation. General information, not medical advice.