Clinically reviewed by Associate Professor Christopher O’Donnell, Nurse Practitioner, FACN · Founder and Clinical Director · AHPRA NMW0001453715 · Last reviewed
The foods that fill you up for the fewest kilojoules are usually high in water, fibre or air, so you get a satisfying volume for little energy. Broth-based soups, air-popped popcorn, berries and melon, legumes and even plain boiled potatoes all do this well. If you’re trying to lose weight and want meals that keep you full, this is the idea to know: eating for low energy density, which lets you eat generous portion sizes while taking in fewer kilojoules. Below are five surprising high-volume, low-calorie foods, the research behind them and how to use them at meals.
Why volume matters: feeling full on fewer calories
Energy density is the number of kilojoules in each gram of food. Water adds weight and volume with no kilojoules, fibre adds bulk with few, and fat adds the most. When the energy density of meals is lowered, studies show adults and children tend to eat fewer kilojoules without deliberately eating less.
To see the difference, here is what about 400 kJ (95 Calories) looks like:
- about 290 g of watermelon, which is a large bowlful
- about 18 g of milk chocolate, which is a few squares
Both provide the same energy, but only one takes up real space in your stomach. That is the idea behind high-volume, low-calorie eating for weight loss: more food on the plate for the same kilojoules.
5 surprising high-volume, low-calorie foods
Figures below are approximate, calculated from Australian food composition data. For kilojoules per 100 g across every food group, see our low-calorie foods list.
| Food | Typical serve | Approximate energy |
|---|---|---|
| Air-popped popcorn | about 20 g (roughly 3 cups) | 310 kJ (75 Calories) |
| Strawberries | 1 cup (about 150 g) | 210 kJ (50 Calories) |
| Blueberries | 1 cup | 320 kJ (75 Calories) |
| Watermelon | about 290 g (a large bowlful) | 400 kJ (95 Calories) |
| Chickpeas or four-bean mix, drained | ½ cup (about 90 g) | 390–430 kJ (95–100 Calories) |
| Boiled potato | 1 medium (about 150 g) | 350–460 kJ (85–110 Calories) |
- Broth-based soup. In one study, starting lunch with a bowl of low-energy-dense vegetable soup reduced total energy intake at the meal by about 20%, whether the soup was chunky or blended. In another, the same ingredients served as a soup were more filling than when eaten as a casserole with a glass of water. Water in food seems to count for more than water alongside it. Keep soups broth-based, as cream and cheese add kilojoules quickly.
- Air-popped popcorn. About 20 g, or roughly 3 cups, provides about 310 kJ (75 Calories). In one study, people felt less hungry and more satisfied after 6 cups of popcorn (about 420 kJ, or 100 Calories) than after 1 cup of potato chips (about 630 kJ, or 150 Calories).
- Berries and melon. A cup of strawberries (about 150 g) has about 210 kJ (50 Calories), and a cup of blueberries about 320 kJ (75 Calories). Watermelon is naturally low in kilojoules, at about 140 kJ (33 Calories) per 100 g.
- Legumes. Half a cup of drained tinned chickpeas or four-bean mix (about 90 g) has about 390 to 430 kJ (95 to 100 Calories), with around 6 grams of protein plus fibre. In a pooled analysis of trials, eating about a serve of legumes a day was linked to a small reduction in weight, even when diets weren’t designed to cut kilojoules.
- Boiled potatoes. A medium boiled potato (about 150 g) has roughly 350 to 460 kJ (85 to 110 Calories). Gram for gram, that is less than cooked rice or pasta. It is frying, butter and creamy toppings that change the picture.
How to build satisfying meals with low-energy-dense foods
Incorporating high-volume foods works best as a way of building meals within a healthy diet, not a list of diet foods. The approach is also called low-energy-density eating, or high-volume, low-calorie eating.
- Start with soup or salad. A broth-based soup or a salad with a light dressing before the main course takes the edge off hunger.
- Bulk up mixed dishes. Add grated zucchini, mushrooms, leafy greens or extra vegetables to mince, pasta sauces and curries, or swap some of the rice for cauliflower rice, to increase volume for few kilojoules.
- Choose fresh fruit over dried. Dried apple has about four to five times the kilojoule (calorie) content of fresh apple per gram, because the water has gone.
- Watch the add-ons. Butter on popcorn, cream in soup and oil on roast vegetables can double the energy of an otherwise light dish.
- Pair volume with protein. Watery, fibre-rich foods fill you up quickly, and high-protein foods such as eggs, yoghurt, legumes or other lean protein help the meal last. See protein and appetite and fibre, gut health and weight.
When to seek review
- If you feel hungry most of the time despite filling meals, or eating is closely tied to stress or mood, it is worth talking it through with a health professional.
- If you have irritable bowel syndrome or a sensitive gut, large increases in legumes and some vegetables can cause bloating. Increase gradually, and a dietitian can help you find foods that suit you.
- If you are already eating very little, focusing only on low-kilojoule foods can leave you short of energy and nutrients.
Our nurse practitioners can review your eating pattern and overall health and help you build meals that keep you full. Get in touch.
Frequently asked questions
What foods are most filling for the fewest calories?
Foods high in water, fibre or protein, such as broth-based soups, legumes, vegetables, whole fruit, eggs and yoghurt, tend to keep you fullest for their kilojoules.
Which foods fill you up the least for their calories?
Energy-dense foods that are low in water and fibre, such as chocolate, fill you up least for their kilojoules. About 18 g of milk chocolate has the same energy as a large bowl of watermelon.
How do filling foods help in a calorie deficit?
If you’re trying to lose weight, lower-energy-density foods let you eat generous portions while taking in fewer kilojoules. Studies show kilojoule (calorie) intake tends to fall this way without people deliberately eating less.
Is popcorn good for weight loss?
Air-popped popcorn is high in volume and low in calories, at about 310 kJ (75 Calories) for 3 cups. Butter, oil and sweet coatings change that quickly.
Are potatoes fattening?
Plain boiled potatoes have fewer kilojoules per gram than cooked rice or pasta. Frying and rich toppings add most of the extra energy.
What are some healthy low-calorie meals I can make?
Start with a broth-based vegetable soup, bulk up mince, pasta sauces and curries with grated zucchini, mushrooms or leafy greens, and choose boiled potatoes over fried. Finish with fresh fruit rather than dried, and keep air-popped popcorn for snacks.
Does drinking water with meals help you feel full?
In one study, water built into food, as in soup, was more filling than the same amount of water drunk with a meal. Drinking water is still worthwhile for hydration.
What is energy density?
It is the number of kilojoules (Calories) per gram of food. Lower-energy-density foods, such as broth-based soups, melon and berries, let you eat more volume for fewer kilojoules.
References
- Food Standards Australia New Zealand. Australian Food Composition Database. https://www.foodstandards.gov.au/science-data/food-nutrient-databases/afcd
- Rolls BJ. Dietary energy density: applying behavioural science to weight management. Nutr Bull. 2017;42(3):246–53. https://pmc.ncbi.nlm.nih.gov/articles/PMC5687574/
- 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
- Rolls BJ, Bell EA, Thorwart ML. Water incorporated into a food but not served with a food decreases energy intake in lean women. Am J Clin Nutr. 1999;70(4):448–55. https://doi.org/10.1093/ajcn/70.4.448
- Nguyen V, Cooper L, Lowndes J, et al. Popcorn is more satiating than potato chips in normal-weight adults. Nutr J. 2012;11:71. https://doi.org/10.1186/1475-2891-11-71
- Kim SJ, de Souza RJ, Choo VL, et al. Effects of dietary pulse consumption on body weight: a systematic review and meta-analysis of randomized controlled trials. Am J Clin Nutr. 2016;103(5):1213–23. https://doi.org/10.3945/ajcn.115.124677