The Volumetric Diet: What Is It & Should I Pay Any Attention To It?
Updated: Feb 14, 2018
As a Registered Dietitian, I am immediately drawn to any headline that promotes a new diet. I mean it’s 2018 – has society not caught on to the fact that 90% of diets don’t work?! Let me clarify - I prescribe certain diets to my clients with specific nutrition-related conditions quite frequently (i.e DASH for those with Hypertension, high fiber for Diverticulosis or a Carb-Controlled diet for patients with Diabetes). BUT – for my patients who I see for weight loss, I ALWAYS interpret the scientific evidence for them: Weight loss diets don’t work --> they are unsustainable and most individuals will regain the weight lost PLUS more in the long-run.
So, when I saw Women’s Health Magazine publish an article claiming the “volumetric diet consistently gets ranked as the best weight loss plan”, I HAD to look into it. To my surprise, the diet was actually created by a nutritional scientist and PhD – at this point I felt not only skeptical, but a bit disappointed. Aren’t we, as nutritional professions, supposed to help the public stay clear of diet culture, not promote it?
Anyways… Let me outline what the Volumetric diet promotes, before I give my clinical opinion…
The premise of the Volumetric diet is that you consume high quantities of foods with elevated water content and fiber (fruits, vegetables and soups). Thus, this diet acts on a satiety claim that you fill up on foods with fewer calories, consequently resulting in weight loss. Foods are broken up into 4 categories:
Group 1: non-starchy fruits and vegetables, nonfat milk and broth-based soups
Group 2: starchy fruits and vegetables, grains, breakfast cereal, low-fat meat, legumes, low fat mixed dishes like chilli and spaghetti
Group 3: meat, cheese, pizza, french fries, salad dressing, bread, pretzels, ice cream and cake
Group 4: crackers, chips, chocolate candies, cookies, nuts, butter and oil
The goal is to consume foods mainly in groups 1 and 2, while being "mindful" of group 3 and "minimising" choices from group 4 (although claiming nothing is completely off-limits). The founder of the Volumetric diet claims that "a diet high in low-density foods and soups will lead to substantial weight loss by increasing satiety". Specifically saying "broth-based soups are very low in energy density and if you eat them before a meal, they can help you eat less". The article also states "since carbohydrates and proteins both provide four calories per gram, and fat provides nine calories per gram, you can eat more [carbs and protein] without the excess calories".
Now for my clinical opinion... I will start with the pros of this diet and then follow with what I believe to be the cons (and yes, there are many, lol).
Positives: This diet promotes an increased consumption in fruits, vegetables, fiber and lean proteins - all of which we know to be beneficial and the foundation for a healthy lifestyle. The diet also claims you don't have to count calories - huge win - because limiting yourself to a certain number of calories is not only draining, but fosters an unhealthy relationship with food. It also claims that no food is off limits, again, WINNING, because a healthy relationship with food does not include cutting out certain food groups or deeming any item "off limits".
Essentially, in my opinion, the core of this diet is scientifically sound - eat a lot of fruits, vegetables, grains, lean proteins, etc. if you want to loose weight. However, the diction the author uses creates A LOT OF PROBLEMS, as well as the exclusion of healthy fat consumption (which the Women's Health Magazine article picked up on, as well).
Negatives: OH MY, where should I begin...
I think my biggest problem with the Volumetric Diet is the attitude towards weight loss - that individuals should consume certain foods to make them feel full so they eat less. This diet encourages us to ignore our physiological needs by masking our hunger with high water content foods - to disobey our hunger hormones and corrupt our satiety hormones....WHAT?!?
Why can't we all just eat foods that not only provide us with energy, nutrients, vitamins, etc., but also foods that we enjoy! Why are health professionals promoting a weight loss strategy that encourages you to "fill-up on broth-based soups to eat less calories"? NEWS FLASH - broth-based soups provide very little nutrition in regards to protein, fats and carbohydrates (the essential macronutrients that ensure survival). I mean, this sounds very similar to the premise of the cabbage-soup diet - and that was busted for its weight lost sustainability claims even in the 90's !
Additionally, this article excludes the consumption of fat. Now, not all fats are created equal. For example, salmon is an incredible source of protein and is packed with all the essential fatty acids. Our body cannot create these fats, so we must consumed them orally to ensure we absorb our fat soluble vitamins, maintain energy stores and cell membrane functionality. Essential fatty acids (think omega 3 and omega 6) promote heart health, produce hormones, increase cognitive function, decrease inflammation and promote a healthy immune system. Other sources of healthy fats excluded by the Volumetric Diet includes nuts, seeds, avocado, and olive oil.
As I said before, I think the core of this diet is alright. We should all increase our consumption of vegetables, fruits and fiber, but not for the sole intention of weight loss and increased satiety. We should increase them because they provide us with a laundry list of health benefits such as plenty of vitamins, minerals, phytochemicals and prebiotics to lower risk of cardiovascular disease, improve our immune system and blood sugar levels. They also promote gut, mental and general health!
Conclusion: I could rant about this weight loss diet for several more pages, but I think you guys get my point. In my clinical opinion, this diet uses language that promotes the diet culture. By labeling certain foods as a "group 4", which should be "minimally" consumed, there is inevitably sense of guilt created around the consumption of said items. Thus, we restrict them, resulting in a later binge, fueling the "restrict-binge-guilt-restrict cycle".
I want to encourage my patients to eat the foods they enjoy, while ensuring they consume all the necessary nutrients and vitamins! I want my clients to eat plenty of fruits, vegetables and fiber, but I always want them to fill up on foods they love - not have a bowl of vegetable broth before each sitting because they want to eat less (restrict) to loose weight. As a registered dietitian, I would not recommend you to follow a Volumetric Diet. I would recommend a well balanced - all foods fit mentality - diet with an increase in exercise, especially if weight loss is your goal.
Please feel free to email me any questions or comments