How to Use the Volumetric Diet to Build Healthy, Sustainable Eating Habits

It's safe and easy to follow.

Volumetric Diet Guide- Vegetable Salad with Halloumi and Pomegranate

Getty Images/Design by Cristina Cianci

If there's one most common complaint about following diets, it’s that restriction leads to a lack of satiety. People on diets are notoriously hungry, and that makes perfect sense: when you limit foods, food quantity, and especially macronutrients like carbs or fat, your body is unlikely to feel as satisfied as when you’re eating all the foods you want in whatever quantities you want. 

There’s been a lot of discovery in recent years about how most diets, in general, have a low success rate, and how obesity alone does not increase a person’s risk of death. All bodies are good bodies worthy of love, and especially of being fed well. There may be times in one’s life where weight loss or a change of diet feels like the right move or has been deemed medically necessary, though. For those times, it’s important to find a plan that isn’t a crash diet, won’t put you on a yo-yo cycle, and doesn’t restrict the nutrients and vitamins your body needs to function.

Rather than a short-term diet, it’s much more healthful for one’s longevity to find a moderate, long-term plan that will nourish you thoroughly. That’s why diets such as the Mediterranean and DASH diets have gained popularity in recent years. Thanks to their more moderate approaches, they yield better results because they’re easier to follow, and people are able to stick with them indefinitely. 

The volumetrics diet is another example of a moderate, less restrictive approach to dieting and eating more healthily. Its basis is simple, it’s easy to follow, and it yields solid long-term results. Keep reading to learn all about what it is and how it works.

Volume Is Key

No surprise here: the volumetrics diet is based on the notion that eating more food makes you feel more full and satisfied. Invented by Barbara Rolls, Ph.D., the diet focuses on eating the largest quantities of foods with the lowest energy density, and the smallest quantities of food with the highest density. That works for weight loss because when you eat a large volume of food, your stomach physically gets full, triggering the release of satiety hormones despite the fact you have been consuming less calories.

Meet the Expert

Barbara Rolls, Ph.D., is a professor and nutrition sciences chair at Penn State University. She has published dozens of studies, as well as numerous books about volumetrics.

The diet doesn’t restrict any specific foods at all, meaning that you never have to live without something you love. That stress relief alone can lead to weight loss, which is a huge bonus. That’s because feeling stressed around the time of eating creates cortisol, our bodies’ key stress hormone, and excess production of that leads to weight gain. It also makes this diet one that’s generally considered safe, as you don’t have to remove any important nutrients or nutrient groups.

The Four Food Categories

The volumetric diet breaks food down into four categories. To follow it, you aim to eat the most from the first category, and the least from the last.

Category One: The foods that are lowest in energy density are the ones with the most water in them. The more water a food has, the more of it you can eat. Foods with high water content include non-starchy vegetables, fruits, and broth-based soups.

Category Two: This category of foods has more caloric density than the first category, but also offers fiber, which leads to satiety. The volumetric diet advises not eating as much of these as produce, but they can (and should) still comprise a good portion of your meals to ensure you're getting proper nutrition. These foods include whole grains, legumes, low-fat dairy, and lean proteins.

Category Three: Many commonly loved ingredients fall into the third category, which you eat less of than category two but still can work into your diet in moderation. These include full fat dairy, higher fat meats, and bread.

Category Four: Foods you eat sparingly on this diet won’t come as any surprise: you’ll limit your intake of fried foods, baked goods like cake and cookies, alcohol, and candy. The only foods that fall into this “eat sparingly” category that are considered healthy by most people are nuts and seeds. As mentioned, though, you can still eat them—you'll just be aiming to have smaller quantities than the foods in the other categories.

How Often You Can Eat

The volumetrics diet doesn’t seek to limit your meals at all. In fact, it’s quite generous with its suggestions on how often you eat, with daily recommendations to eat three full meals and two snacks, plus dessert some days. For each meal or snack, you’ll want to follow the category guidance, eating the most volume of food from category one, and the least, if any, from category four.

Calorie Limits

The numeric premise for calories consumed on this diet is that if you reduce your daily intake by 500 to 1,000 calories a day, you’ll lose one to two pounds a week. That’s a diet industry standard based on the notion that a pound of body fat equals 3,500 calories. That theory has seen some upheaval in recent years, but there hasn’t yet been a better one to take its place.

Ultimately, this means you can adjust the calories you consume depending on your goals and what your body needs: to adopt the volumetric diet's intended moderate, long-term approach, you'll want to find a balance that ensures you feel properly nourished.

The Science Backing

Studies have shown a direct link between the energy density of food that people eat and what their weight is. One meta-analysis that looked at multiple studies noted that “regulating the energy density of food could be used as a novel approach for successful body weight reduction in clinical practice.” Another individual study on the topic stated that “preliminary findings suggest that consuming a diet lower in ED, characterized by greater intake of vegetables and whole grains, may aid with weight loss maintenance and should be further tested in prospective randomized controlled trials.” This isn’t new information for most people, as the overarching message about healthy eating is to eat more produce, whole grains, and lean proteins, and fewer processed foods and added sugars. By adopting a balanced diet that keeps you feeling full and energized while still enjoying whatever foods you love in moderation, you're setting yourself up for success both in sticking with your new habits and in how strong and healthy you'll look and feel.

What a Day Looks Like

You can find several books on the volumetrics diet, detailing both its methodologies and the recipes that work best for followers. It’s pretty straightforward, though, and unless you want to take a deep dive right from the start, you should be able to try this out with just some simple calculation. Here is an example of what a day following this diet could look like, with quantities dependent on your regular calorie intake prior to starting.

Breakfast: Oatmeal plus a citrus fruit like grapefruit, or a vegetable frittata and melon, or cereal with low-fat (or unsweetened plant-based) milk.

Lunch: Salad with chicken breast and a slice of whole grain bread, or a bowl of bean soup with a side salad, or an open-face tuna sandwich.

Dinner: Poached fish with brown rice and greens, or chicken with mixed grains and Brussels sprouts, or a bison steak with a vegetable medley.

Snacks: Low-fat yogurt, or fruit, or whole grain crackers with hummus.

Dessert: Fruit, or sugar-free pudding, or a fruit crumble.

Important Note: You Still Need Fat

Because this diet focuses on eating the highest quantity of foods with the lowest density, you’ll want to make sure you’re still getting enough fat. Fat is as dense in calories as food gets, so you may be tempted to eschew it in favor of more voluminous food, but take care to not reduce it drastically from your diet. Sufficient fat intake is vital to everything from brain functioning to skin’s ability to stay hydrated, so you'll want to make sure you're working in some healthy fats, which you can get from sources like avocados and olive oil.

How to Get Going

To start the volumetrics diet, you need only to restructure the quantities of foods you eat. There are no meetings to attend, or supplies to purchase: just factor the basics of what you plan to eat into your next grocery run, and you’ll be on your way.

Related Stories