Low-calorie foods: the honest list
The least calorie-dense foods, sorted by category and in kcal per 100 g. What “low calorie” really means — and why, on its own, it won't make you lose weight.
A food is “low calorie” when it provides little energy for its volume — that's calorie density, in kcal per 100 g. The champions are packed with water and fibre: they fill the plate and the stomach without weighing on the day's total. Here are the benchmarks, to read as ranges (variety, cooking and seasoning move the number).
Indicative values per 100 g, raw or plain unless noted. Tap a food for its detailed page.
Vegetables: under 40 kcal per 100 g
These are the lowest-calorie foods there are. Rich in water and fibre, they fill you up for almost nothing: the base of a satisfying plate on a small calorie budget.
Fruit: freshness under 60 kcal
Sweeter than vegetables, but still not dense. Perfect for a sweet craving without blowing up the counter — berries and watermelon are the lightest.
Lean proteins: few calories, plenty of satiety
More calories than vegetables, but far more filling: protein curbs hunger for longer. The best satiety-to-calorie ratio to hold a deficit without cracking.
Low-fat dairy: protein you can spread
Ideal at breakfast or as a snack: lots of protein, little fat, and a genuine appetite-curbing effect.
“Negative-calorie” foods: myth or reality?
You read everywhere that celery or cucumber “burn more calories than they contain.” That's false — but the idea hides a useful truth.
No food has a negative balance. Digesting a meal only uses about 5 to 15% of its energy (the thermic effect of food). Even cucumber at 15 kcal leaves a positive balance: you don't lose weight “by eating.”
But calorie density is very real. Filling your plate with vegetables and lean proteins means eating a big volume for few calories. You feel full while staying in a deficit: that's the real lever.
What matters is the day's total. A low-calorie food won't make you lose weight on its own — you lose weight in a calorie deficit across your whole intake. These foods make that deficit liveable without going hungry.
Frequently asked questions
What are the lowest-calorie foods?+
Water-rich vegetables lead: cucumber, lettuce, celery, courgette and radish sit around 12 to 20 kcal per 100 g. Among fruit, watermelon, strawberries and melon stay below 35 kcal per 100 g.
Do negative-calorie foods really exist?+
No. No food makes you burn more calories than it provides: digestion only uses about 5 to 15% of a meal's energy. Celery and cucumber are very low in calories, but their balance stays positive.
Does eating low-calorie foods make you lose weight?+
Not on their own. You lose weight by being in a calorie deficit across the whole day. Low-calorie, filling foods (vegetables, lean proteins) help you hold that deficit without feeling hungry.
Which proteins are lowest in calories?+
White fish like cod and pollock (75 to 90 kcal/100 g), prawns, chicken or turkey breast, plus fat-free fromage blanc and skyr. They keep you full for very few calories.
How do I know the calories on my plate?+
Per-100 g values are a baseline, but your real portion differs. Snap your plate with Volumeal to get a range estimate matched to what you actually eat.