Clinically reviewed by Associate Professor Christopher O’Donnell, Nurse Practitioner, FACN · Founder and Clinical Director · AHPRA NMW0001453715 · Last reviewed
If you’re trying to lose weight, the lowest-kilojoule foods are those high in water and fibre and low in fat: most vegetables and fruit, broth-based soups, legumes, lean proteins and reduced-fat dairy. Building meals around these low-calorie foods lets you eat generous portions for fewer kilojoules (Calories). Below is a practical low-calorie food list by food group, with typical energy values per 100 g from Australian food composition data, plus simple swaps.
Low-calorie food list at a glance
The lowest-kilojoule everyday foods, from lowest to highest per 100 g. Figures are approximate and rounded; raw unless stated, and with no added fat.
| Food | kJ per 100 g | Calories per 100 g | Group |
|---|---|---|---|
| Cucumber | 50 | 12 | Vegetable |
| Lettuce | 65–75 | 16–18 | Vegetable |
| Baby spinach | 70 | 17 | Vegetable |
| Zucchini | 70 | 17 | Vegetable |
| Green capsicum | 70 | 17 | Vegetable |
| Tomato | 75 | 18 | Vegetable |
| Cauliflower | 105 | 25 | Vegetable |
| Mushrooms | 105 | 25 | Vegetable |
| Watermelon | 140 | 33 | Fruit |
| Strawberries | 140 | 33 | Fruit |
| Broccoli | 140 | 33 | Vegetable |
| Skim milk | 150 | 36 | Dairy |
| Carrot | 150 | 36 | Vegetable |
| Orange | 185 | 44 | Fruit |
| Apple | 220–260 | 53–62 | Fruit |
| Regular milk | 275 | 66 | Dairy |
| Grapes | 280–370 | 67–88 | Fruit |
| Natural yoghurt | 310 | 74 | Dairy |
| Cannellini beans, canned, drained | 410 | 98 | Legume |
| Banana | 410 | 98 | Fruit |
| Chickpeas, canned, drained | 475 | 114 | Legume |
| Prawns, cooked | 510 | 122 | Protein |
| Tuna in water, drained | 540 | 129 | Protein |
| Firm tofu | 540 | 129 | Protein |
| Flathead or snapper, baked | 540–555 | 129–133 | Protein |
| Cottage cheese | 555 | 133 | Dairy |
| Kangaroo loin, grilled | 560 | 134 | Protein |
| Eggs, boiled | 570 | 136 | Protein |
| Chicken breast, skinless, grilled | 600 | 143 | Protein |
For comparison, regular cheddar is about 1,680 kJ (400 Calories) per 100 g, and oils and nuts are higher still. Per-100 g figures compare foods fairly, but portion sizes decide what you actually eat.
Energy density, explained
Energy density is the number of kilojoules in a given weight of food. It depends mostly on three things:
- Water, which adds weight and volume but no kilojoules
- Fat, which provides about 37 kJ (9 Calories) per gram
- Carbohydrate and protein, which provide about 17 kJ (4 Calories) per gram each
Research suggests people tend to eat a fairly consistent weight of food from day to day. When the foods on the plate are lower in energy density, kilojoule (calorie) intake falls without portions shrinking. Clinical trials that lowered energy density mainly by adding water-rich foods such as fruit and vegetables have been associated with meaningful weight loss.
As a rough guide:
| Energy density | kJ per 100 g | Examples |
|---|---|---|
| Very low | under about 250 | most non-starchy vegetables, salad greens, berries, citrus, melon and broth-based soups |
| Low | about 250–650 | bananas, grapes, potatoes, legumes, eggs, white fish, lean chicken and kangaroo, yoghurt, cottage cheese |
| Medium | about 650–1,700 | bread, breakfast cereals, reduced-fat cheese |
| High | over about 1,700 | nuts, oils, chocolate, chips and biscuits |
High-calorie, energy-dense foods aren’t off limits. Nuts and olive oil are nutritious sources of healthy fats; they just need measuring, since a 30 g serve of nuts is about 700–900 kJ (170–215 Calories) depending on the nut. Many packaged snack foods are also energy-dense, as our article on ultra-processed food explains, so compare nutrition panels per 100 g. Low-kilojoule foods work well within a healthy diet that still includes nutrient-rich foods from all five food groups.
If you want the options that fill you up most for the fewest kilojoules, see our guide to low-calorie filling foods.
Low-calorie vegetables and fruit
Australia’s dietary guidelines count about 75 g of vegetables as one serve, providing roughly 100–350 kJ, and 150 g of fruit as one serve, about 350 kJ. They also note it makes sense to fill up on leafy greens and other lower-kilojoule vegetables when trying to lose weight. Adults are advised to aim for five to six serves of vegetables and two of fruit a day.
Low-calorie vegetables
Approximate kilojoules per 100 g, raw: cucumber 50, lettuce 65–75, zucchini 70, green capsicum (bell pepper) 70, tomato 75, baby spinach 70, cauliflower 105, mushrooms 105, broccoli 140, carrot 150. Most non-starchy vegetables are naturally low in kilojoules, at under about 250 kJ per 100 g.
Low-calorie fruits
Approximate kilojoules per 100 g, raw: watermelon 140, strawberries 140, orange 185, apple 220–260, grapes 280–370, banana 410.
Practical tips:
- Aim for about half your plate as vegetables at main meals, such as salad greens, broccoli, zucchini or mushrooms
- Fresh vegetables, frozen vegetables and canned vegetables (no added salt or sugar) all count
- Roast or stir-fry with a measured spray or teaspoon of oil. One Australian tablespoon (20 mL) of oil adds about 670 kJ (160 Calories)
- Choose whole fresh fruit over fruit juices and dried fruit, which the guidelines suggest having only occasionally
Lean proteins and legumes
A serve from this group, which includes lean meat and poultry, fish, eggs, tofu and legumes, provides about 500–600 kJ. Approximate kilojoules per 100 g as eaten, with no added fat:
- Flathead or snapper fillet, baked: 540–555
- Prawns, cooked: 510
- Tuna canned in water, drained: 540
- Kangaroo loin, grilled: 560
- Eggs, boiled: 570
- Chicken breast, skinless, grilled: 600 (about 810 baked with skin)
- Firm tofu: 540
- Chickpeas, canned and drained: 475
- Cannellini beans, canned and drained: 410
Grilling, baking, steaming and poaching keep kilojoules down compared with frying. Choosing lean cuts, trimming visible fat and removing chicken skin also helps. Legumes are among the most useful foods in this group: inexpensive, high in fibre and easy to add to soups, salads and mince dishes. See our article on fibre and weight.
Dairy, soups, herbs and spices
Reduced-fat dairy
The guidelines suggest choosing mostly reduced-fat (low-fat) dairy. Approximate kilojoules per 100 g: skim milk 150, regular milk 275, natural yoghurt 310, cottage cheese 555, ricotta 640, reduced-fat cheddar 1,350, regular cheddar 1,680.
Broth-based soups
Broth-based vegetable soups are among the lowest-energy-density meals you can make. In one controlled study, having vegetable soup before lunch reduced total energy intake at the meal by about 20%. Cream-based soups are a different matter, and packet soups vary, so check the label for kilojoules per serve as prepared.
Herbs and spices
Garlic, ginger, chilli, fresh herbs, citrus, vinegar, mustard and dried spices add flavour for almost no kilojoules. They make it easier to build satisfying meals without creamy sauces and extra oil. Stock cubes and bottled sauces can be high in salt, so choose reduced-salt versions.
Healthy eating swaps for fewer calories
Small food choices add up across a weight-loss plan. These swaps use the figures above:
| Instead of | Try |
|---|---|
| Regular cheddar (about 1,680 kJ per 100 g) | Reduced-fat cheddar (1,350 kJ) or cottage cheese (555 kJ) |
| Regular milk (275 kJ per 100 g) | Skim milk (150 kJ) |
| Chicken baked with skin (about 810 kJ per 100 g) | Skinless chicken breast, grilled (600 kJ) |
| Free-poured oil (about 670 kJ per tablespoon) | A measured spray or teaspoon |
| Frying | Grilling, baking, steaming or poaching |
| Cream-based soup | Broth-based vegetable soup |
| Fruit juice or dried fruit | Whole fresh fruit |
| Creamy sauces | Herbs, spices, citrus, vinegar or mustard |
When to seek review
If you’re eating mostly lower-kilojoule foods but feel constantly hungry, tired or aren’t making progress, an individual review can help. Get personal advice before major changes if you have a digestive condition, diabetes, kidney disease, or a history of disordered eating.
An Accredited Practising Dietitian can tailor these ideas to your preferences, budget and health. Our dietitians and nurse practitioners can help you put a plan together. Get in touch.
Frequently asked questions
What is the lowest-calorie food?
Cucumber, lettuce and celery sticks are among the lowest, at about 50–75 kJ (12–18 Calories) per 100 g, because they are mostly water.
What are the 10 lowest-calorie foods?
In the table above, the 10 lowest per 100 g are cucumber, lettuce, baby spinach, zucchini, green capsicum, tomato, cauliflower, mushrooms, watermelon and strawberries, with broccoli level with the last two at about 140 kJ (33 Calories).
What are some low-calorie fruits?
Watermelon and strawberries are among the lowest, at about 140 kJ per 100 g, followed by oranges at about 185 kJ and apples at about 220–260 kJ.
Can I eat as many vegetables as I like?
Non-starchy vegetables are so low in kilojoules that generous portions are fine for most people. Watch added oil, butter, cheese and creamy salad dressing.
Is fruit too high in sugar for weight loss?
No, whole fruit has a low to moderate energy density and provides fibre and nutrients. Two serves a day is the adult recommendation.
Are low-calorie packaged foods a good choice?
Sometimes. Check the nutrition panel per 100 g and the ingredients list, because “light” or “diet” labels don’t always mean fewer kilojoules than plain whole foods.
Is calorie counting necessary if I eat these foods?
Not necessarily. Choosing low-energy-dense foods often reduces intake without counting kilojoules, though some people find a short period of tracking useful.
References
- Eat for Health (NHMRC). Serve sizes. https://www.eatforhealth.gov.au/food-essentials/how-much-do-we-need-each-day/serve-sizes
- Eat for Health (NHMRC). Recommended number of serves for adults. https://www.eatforhealth.gov.au/food-essentials/how-much-do-we-need-each-day/recommended-number-serves-adults
- National Health and Medical Research Council, New Zealand Ministry of Health. Nutrient Reference Values for Australia and New Zealand: Dietary energy. https://www.eatforhealth.gov.au/nutrient-reference-values/nutrients/dietary-energy
- Food Standards Australia New Zealand. Australian Food Composition Database. https://www.foodstandards.gov.au/science-data/food-nutrient-databases/afcd
- Rolls BJ. The relationship between dietary energy density and energy intake. Physiol Behav. 2009;97(5):609–15. https://doi.org/10.1016/j.physbeh.2009.03.011
- Flood JE, Rolls BJ. Soup preloads in a variety of forms reduce meal energy intake. Appetite. 2007;49(3):626–34. https://doi.org/10.1016/j.appet.2007.04.002