What calorie density means
Calorie density (also called energy density) is the number of calories in a gram of food. It runs from 0 calories per gram for water up to 9 for pure fat, and it depends mostly on how much water, fibre and fat a food contains. Water adds weight with no calories, fibre has about 2 calories per gram, carbohydrate and protein about 4, alcohol 7 and fat 9 [1].
Nutrition researchers usually group foods into four bands [1]:
| Band | Calories per gram | Typical foods |
|---|---|---|
| Very low | 0 to 0.6 | Most fruit and vegetables, broth-based soups, skimmed milk |
| Low | 0.6 to 1.5 | Cooked grains, lean meat and fish, cooked beans and lentils |
| Medium | 1.5 to 4 | Fattier meat, cheese, bread, dry rice and pasta |
| High | 4 to 9 | Nuts, seeds, crisps, biscuits, butter and oils |
A low calorie food is simply one with a lot of water or fibre for its weight. A plate of broccoli and a handful of walnuts can weigh the same and differ twentyfold in calories.
Calorie dense foods vs low calorie foods compared by cost
The infographic on this page, made by James Fortis and posted on Reddit in October 2024, compares 49 whole foods on two measures: calories per gram, and what 100 calories of each cost at Walmart in North Carolina. Calorie values came from USDA FoodData Central [2]. The pattern is clear: the denser the food, the cheaper its calories tend to be.
| Food | Calories per gram | Approx. cost per 100 calories (2024) |
|---|---|---|
| Brown rice (dry) | 3.67 | $0.05 |
| Wholewheat spaghetti (dry) | about 3.7 | $0.06 |
| Lentils (dry) | 3.52 | $0.09 |
| Peanuts | 5.70 | $0.09 |
| Banana | about 0.9 | $0.13 |
| Oats | about 3.8 | $0.14 |
| Whole egg | about 1.4 | $0.17 |
| Walnuts | 6.54 | $0.20 |
| Potatoes | about 0.8 | $0.27 to $0.31 |
| 80% ground beef | about 2.5 | $0.44 |
| Broccoli | about 0.3 | $0.77 |
| Chicken breast | about 1.2 | $0.84 |
| Ribeye steak | about 2.6 | $1.39 |
| Mushrooms | 0.31 | $2.22 |
Costs other than the mushroom figure are read from the plotted positions, so treat them as approximate. Calorie values for rice, lentils, peanuts and walnuts are the USDA figures [3][4][5][6]. Across all 49 foods the middle value was about 38 cents per 100 calories.
To put the spread in everyday terms: 2,000 calories, roughly a day’s worth for an adult, would cost about $1 in dry brown rice and about $15 in broccoli, and you would need to eat about 6 kilograms of broccoli to get there.
Is shrimp calorie dense?
No. Farmed shrimp appears on the graphic at about 3.5 calories per gram and 56 cents per 100 calories, alongside dry grains and beans. That is wrong. The creator confirmed in the comments on his original post that he had taken the kilojoule figure for shrimp from USDA instead of the kilocalorie figure [2]. USDA lists raw shrimp at 85 calories per 100 grams, or 0.85 calories per gram (99 per 100 grams cooked) [7].
With the right figure, shrimp costs roughly $2.30 per 100 calories at the same price, which makes it one of the most expensive foods on the chart per calorie, next to mushrooms, and in line with the other seafood.
Why calorie dense foods cost less per calorie
Researchers have found the same pattern across whole diets, not just a list of supermarket foods. Adam Drewnowski and Nicole Darmon describe an inverse relationship between how calorie dense a food is and what its calories cost: refined grains, added sugars and added fats are among the cheapest sources of energy, while lean meat, fish, fresh vegetables and fruit generally cost more per calorie [8].
The reason is mostly water. You pay for food by weight, and a kilogram of lettuce or fish fillet is largely water, while a kilogram of dry rice, oil or nuts is almost all energy.
The flip side, according to the same research, is that cheap energy-dense diets tend to be lower in nutrients, and energy-dense foods are less filling for their calories, which makes it easier to overeat [8].
Dry weight vs cooked weight
Most comparisons of cost per calorie use foods as you buy them, which matters for grains and pulses. Dry brown rice has 367 calories per 100 grams, but cooked brown rice has about 123, because it absorbs water [3][9]. Dry lentils have 352 calories per 100 grams and boiled lentils 116 [4][10]. The cost per calorie doesn’t change when you add water, but the calorie density on your plate does, which is why cooked rice and beans count as low energy density foods in the bands above [1].
Calorie density and weight loss
If you want to lose weight, low calorie foods are useful because you can eat larger, more filling portions for the same calories. Barbara Rolls, a nutrition scientist at Penn State who has researched energy density for many years, argues that lowering the calorie density of your diet is effective for weight loss and for keeping weight off, and that it works with almost any eating pattern [1][11]. In practice that means filling up on vegetables, fruit, soups and lean protein, and watching portions of nuts, oils and other high-density foods.
If your aim is the opposite (gaining weight, bulking, or simply feeding a household on a tight budget), calorie dense foods do the job cheaply. Rice, pasta, oats, dried beans and lentils, peanuts and peanut butter, and cooking oil give the most calories for the money.
Getting cheap calories without losing nutrition
- Base meals on dry staples such as rice, oats, pasta and pulses. They are the cheapest calories and pulses add protein and fibre.
- Use eggs, peanuts and sunflower seeds for cheap protein and fat. Whole eggs cost about 17 cents per 100 calories on the chart, far less than egg whites.
- Buy bananas, potatoes, carrots and frozen vegetables for low cost fruit and veg.
- Treat lean fish, steak and out-of-season berries as the expensive part of the shop, and use smaller amounts.
Prices change and vary by shop and country, so check unit prices where you buy. The ranking of cheap and expensive foods tends to hold even when the exact numbers move.
Questions about calorie dense foods vs low calorie foods
What is the cheapest food per calorie?
Among whole foods, dry grains and pulses are usually the cheapest. On the 2024 Walmart prices behind the infographic, brown rice cost about 5 cents per 100 calories and wholewheat spaghetti about 6 cents, with lentils, split peas, chickpeas, pinto beans, peanuts and sunflower seeds under 10 cents [2]. Added fats and sugars are also among the cheapest sources of calories, but they supply few nutrients [8].
What is the average cost per calorie?
There is no single average, because it depends on what you buy. Across the 49 whole foods on this chart, the middle value was about 38 cents per 100 calories, ranging from about 5 cents for rice to $2.22 for mushrooms at 2024 prices [2].
Are calorie dense foods unhealthy?
Not necessarily. Nuts, seeds, oats and beans are calorie dense and nutritious. The issue is that many calorie dense processed foods are low in nutrients and easy to overeat, so it helps to keep an eye on portions [1][8].
Which low calorie foods keep you full?
Foods high in water and fibre, such as vegetables, fruit, broth-based soups, cooked beans and lentils, and lean protein, give large portions for few calories, which helps you feel full [1][11].
Which food has the most calories per gram?
Pure fats such as oils and butter, at around 9 calories per gram [1]. Of the whole foods on the infographic, walnuts are the densest at 6.54 calories per gram [6].
Sources
- Smethers AD and Rolls BJ, Dietary management of obesity: cornerstones of healthy eating patterns, Medical Clinics of North America, 2018.
- James Fortis (u/James_Fortis), [OC] Food’s Cost vs. Caloric Density, r/dataisbeautiful, 1 October 2024 (sources and the shrimp correction are in the creator’s comments).
- USDA FoodData Central, Rice, brown, long-grain, raw (FDC ID 169703).
- USDA FoodData Central, Lentils, raw (FDC ID 172420).
- USDA FoodData Central, Peanuts, valencia, raw (FDC ID 172432).
- USDA FoodData Central, Nuts, walnuts, english (FDC ID 170187).
- USDA FoodData Central, Crustaceans, shrimp, raw (FDC ID 175179).
- Drewnowski A and Darmon N, The economics of obesity: dietary energy density and energy cost, American Journal of Clinical Nutrition, 2005.
- USDA FoodData Central, Rice, brown, long-grain, cooked (FDC ID 169704).
- USDA FoodData Central, Lentils, mature seeds, cooked, boiled, without salt (FDC ID 172421).
- Rolls BJ, What is the role of portion control in weight management?, International Journal of Obesity, 2014.
Last reviewed 6 November 2026
