Evidence-based nutrition, in plain English — every entry sourced from clinical research.

Calorie density is a genuinely useful number when you’re trying to eat a larger volume of food for fewer calories — a common goal for weight management without feeling like you’re eating less. Below is a data-backed ranking of the foods in our database with the fewest calories per 100 g.

Foods ranked by Calories per 100 g edible portion
#FoodCalories
1Coffee1 kcal
2Green Tea1 kcal
3Cucumber15.9 kcal
4Celery16.7 kcal
5Courgette (Zucchini)17 kcal
6Tomato18 kcal
7White Mushrooms22 kcal
8Spinach23 kcal
9Cauliflower27.6 kcal
10Asparagus28.1 kcal
11Grapefruit30 kcal
12Watermelon30 kcal
13Red Bell Pepper31.3 kcal
14Cabbage31.4 kcal
15Broccoli34 kcal
16Skim Milk34 kcal
17Kale35 kcal
18Strawberries36.4 kcal
19Peach39 kcal
20Chilli Pepper40 kcal
21Green Beans40 kcal
22Carrot41 kcal
23Beetroot43 kcal
24Blackberries43 kcal
25Kefir43 kcal

Unsurprisingly, this list is dominated by water-rich vegetables, unsweetened drinks and leafy greens — cucumber, celery and spinach among them. Low calorie density doesn’t mean low nutritional value: many of these foods are genuinely rich in vitamins, minerals and fibre, just delivered with a lot of water weight alongside.

Common questions

Is “low calorie” the same as “healthy”? Not automatically — a food can be low in calories and still offer little nutritionally. The foods ranked here are whole, minimally processed foods that happen to also be calorie-light, not ultra-processed diet products.

Why do some low-calorie foods still feel filling? Volume and water content play a big role — foods with high water and fibre content, like vegetables, tend to fill the stomach for relatively few calories, which is part of why they’re a mainstay of most weight-management approaches.

Nutrition values are USDA FoodData Central approximations — see our editorial approach for how we source and verify data.