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Some sources claim that up to 95% of diet attempts fail. While it’s hard to verify this number, it’s probably not that far off.

But are the people failing their diets? Or are the diets failing the people?

See, the basis of most diets is deprivation: The goal is to restrict yourself from eating. And while that might seem like the logical thing to do. Especially when you consider you need to consume less calories than you burn to lose weight.

With this approach, you keep seeing the same thing happen over and over again: People either fail. Or they lose some weight only to gain it back shortly after.

However, what if you could lose weight by eating more instead of eating less? That’s the promise the Volumetric diet makes. But is such a thing even possible? Let’s get into it.   

What is the Volumetric diet?      

Who invented it?

The person who originated the Volumetric diet is Barbara Rolls. Now, she’s not just your average person who came up with a weight loss program. Barbara Rolls holds a Ph.D. in Nutritional Science.

She has written over 3 books on food and nutrition. And published over 170 scientific papers. 

Is it possible to lose weight by eating more?

Yes, it is. How? By eating lots of low “energy-dense” food. You see, each food has a ratio between how much it weighs and how much calories it contains. The fewer calories a food contains compared to its weight, the better.

Because these foods fill you up even though you’re only eating a small number of calories.

An example is foods high in water content: Most vegetables and fruits contain over 90% water, which is why they only contain a small number of calories. 

What does the research say about the Volumetric diet?

Researches have been done on how eating low energy-dense foods affects weight loss. Eating Behaviors found there was a positive relationship between eating energy-dense foods and your body mass index [1]

(BMI.) After going over 13 different studies, Nutrients concluded that it could help obese people manage their weight[2]. And the U.S. News gave the Volumetric Diet the second place for best weight loss diet. It was voted by a panel of nutrition and weight loss experts.

How does it work?

The Volumetric diet all comes down to making smart food choices. It divides all foods into four groups based on their energy density:

  • Group 1:  Foods in group 1 are the lowest in energy density. You should eat as many foods in this group as possible. And you’re allowed to eat them whenever you want. Foods in this group include non-starchy fruits and vegetables, nonfat milk and broth-based soups
  •  Group 2: Foods in group 2 are a little bit higher in calories than the foods in group 1. But they’re still low in calories overall. You should be eating a lot of foods from this group as well. Foods in this group include grains, legumes, low-fat meats, and starchy fruits and vegetables.
  •  Group 3: Foods in group 3 are medium-dense foods. And tend to be higher in (unhealthy) fats, refined carbs, or sugar. You should eat foods in group 3 in moderation. And preferably in small portions. Foods include meat, cheese, pizza, French fries, salad dressing, bread, pretzels, ice cream, and cake
  • Group 4: Foods in group 4 are the highest in calories. And should only be eaten on rare occasions. Exceptions are special occasions and moments where you want to treat yourself. Foods in this group include chips, chocolate candies, cookies, nuts, butter, and oil

What foods are important in the Volumetric diet?

  • Fruits and vegetables
  • Low-fat dairy products
  • Whole grains
  • Lean protein
  • Fresh fruits (rather than dried fruit or juice, for example)
  • Fresh or frozen vegetables (try swapping some in for half a portion of pasta in a pasta dish, for example)
  • Beans and legumes
  • Whole grains
  • Fiber-rich breakfast cereals
  • Low-fat fish
  • Poultry without skin
  • Lean meats
  • Minimal added sugars
  • Water (rather than sugary drinks)

What are the benefits of the Volumetric diet?

Research has highlighted some of the health benefits of the Volumetric diet. If you follow the Volumetric diet, you:

  • Decrease the risk of developing Cardiovascular disease[3]
  • Have a lower risk of developing Type 2 diabetes[4]
  • Have a lower risk of developing breast cancer[5]

The Volumetric diet also has some specific advantages over other diets:

  • Lose weight while eating more food
  • It doesn’t restrict you from eating any foods
  • Once you’ve adopted it, it’s easy to maintain long term
  • It focuses on eating more of the foods people tend not to eat enough of
  • Because it helps to stabilize blood sugar levels, it’s one of the best diets to prevent 2 Diabetes.

Are there any downsides to the Volumetric diet?

With being said, depending on your personality, there could be some downsides to the Volumetric diet. It may not be the best option IF you’re the type of person:

  • Who HATES eating lots of veggies, fruits, and soups.
  • Needs strict rules to accomplish goals: The Volumetric diet only provides guidelines.


It is possible to lose weight while eating more food: By following the Volumetric, which focuses on eating more foods that are low in energy density. The number of calories a food contains compared to its weight.

In fact, it’s so effective that it was given second place on the best weight loss diets list by US News. If you want to try the Volumetric diet, I recommend reading the following books: