Low-calorie, high-volume foods

Why volume works

People tend to eat a fairly steady weight of food each day. Foods with low energy density, meaning few calories per gram, let you eat that same weight for fewer calories. Penn State researcher Barbara Rolls built the "volumetrics" approach on this idea, and it's one of the most practical tools for feeling full while losing weight.

Energy density is easy to spot. Foods with lots of water and fiber, like vegetables, fruit, broth soups and lean proteins, are low. Foods with little water and lots of fat or sugar, like chips, cookies, nuts and oils, are high. You don't have to avoid the high ones. Just let the low ones take up more of the plate.

20 foods with the numbers

Values are approximate.

Easy ways to bulk up meals

• Half-and-half: mix rice with riced cauliflower, or pasta with zucchini noodles.
• Start with soup or salad: a broth-based soup or a big salad with light dressing before dinner can lead to eating less overall.
• Load sandwiches and wraps with lettuce, cucumber and peppers.
• Add vegetables to eggs, sauces and chili without much extra effort.

Common volume-eating mistakes

• Drowning the salad. A big salad is a great start, but 4 tablespoons of creamy dressing can add 250 to 300 calories. Measure 2 tablespoons, or use a light vinaigrette.
• Volume without protein. A plate of vegetables fills your stomach, but hunger often returns fast. Pair vegetables with a palm-sized portion of protein.
• Roasting with a heavy hand. Vegetables soak up oil. A tray of roasted broccoli with 3 tablespoons of oil adds about 360 calories. One tablespoon is usually enough.
• Jumping from low fiber to high fiber overnight. Going from a few vegetables a day to bowls of them can cause gas and bloating. Build up over a couple of weeks and drink more water.

Who should be a bit careful

If you have IBS, Crohn's disease or another gut condition, some high-fiber or raw vegetables may cause symptoms. Cooked vegetables and smaller portions often sit better, and a registered dietitian can help you find your best options.

High-volume eating should feel freeing, not strict. If counting, measuring or always choosing the "lowest calorie" option starts to feel stressful or all-consuming, that's worth talking about with a clinician you trust. Food is also for enjoyment and connection, and a balanced plan has room for both.

A sample high-volume day

Here's what a day built on volume can look like at roughly 1,600 calories, a level many people use while losing weight (your target may differ: find yours):

That's a lot of food on the plate, with protein at every meal. Watch the calorie-dense extras that can quietly undo a high-volume plan: oils, dressings, cheese, nuts and dried fruit. They're healthy in measured amounts, but a heavy hand can add several hundred calories without adding much volume.

The verdict, and a GLP-1 note

High-volume foods are one of the best tools for most people trying to lose weight. On a GLP-1 medicine, though, your stomach empties more slowly and fills fast, so very large salads can crowd out protein. In that case, eat protein first and treat volume foods as the side: eating on a GLP-1.