What is the Volumetrics diet?

The Volumetrics diet, developed by Dr Barbara Rolls, focuses on eating foods that provide the volume of a hearty meal but with fewer calories. The idea is to feel satisfied by eating more food in terms of weight, while actually consuming fewer calories than a typical meal of the same size.

Helena Barham-Coppola, nutritional therapist and founder of Nourish&Be, London, UK shares a simple snapshot of what a Volumetrics-style meal or snack might include.

“For example, 50 calories of crisps would be around 10 grams, or a small handful," she says. "50 calories of watercress, on the other hand, would be around 450 grams - so 4-5 supermarket bags. A mountain of greens in comparison.”

Barham-Coppola goes on to explain that the Volumetrics diet groups foods into four categories.

1. Low-calorie-density foods - examples include non-starchy vegetables, fat-free yoghurt, and broths.

2. Foods to eat in moderation - including skinless chicken or turkey, lean cuts of beef or pork, lentils, beans, pulses, whole grains, and starchy vegetables, such as beetroot and sweet potatoes.

3. Foods best enjoyed in small portions - for example, fatty meats and fish, ice cream, whole milk, cheese, pasta, and bread.

4. Foods to eat sparingly - such as nuts, seeds, oils, and fast food.

Helena Barham-Coppola

The Volumetrics diet, while promoting weight loss, offers several general health benefits. By encouraging a higher consumption of vegetables, the diet helps to increase your intake of essential vitamins, fibre, and water, all of which support overall health.

However, Barham-Coppola does not recommend it as a healthy long-term practice, for reasons she outlines below.

Nutritional limitations and outdated advice

The Volumetrics diet has been around for a quarter of a century, pre-dating many recent advancements in nutritional science.

"This diet was created in 2000, back when low fat was all the rage,” Barham-Coppola notes. “Nutrition has moved on since then."

Weight loss and practicality

Wenn weight loss is your goal, the plan does have some merits. However, Barham-Coppola points out areas that may encourage unhealthy habits and even lead to feelings of isolation.

• Complexity - the method of counting calories is viewed as potentially obsessive and effortful. This is especially true if you’re on a weight loss journey, which doesn’t need the added pressure of mathematical tasks.

• Social and practical hurdles - the diet can make eating out extremely difficult, which may in turn increase your likelihood of social isolation.

Barham-Coppola suggests that the plan shouldn't be followed for more than a couple of weeks, and ideally should be supervised by a professional to ensure your basic nutritional needs are met.

Long-term concerns and health effects

Barham-Coppola does not recommend following this approach long-term. She raises concerns about its potential impact on your health over time and cautions that it could contribute to disordered eating patterns and feelings of social isolation.

“Following the diet long-term may reduce your intake of fat-soluble vitamins,” she says. “This includes the ever-important Vitamin D, which so many people in the UK are already deficient in.”

Barham-Coppola concludes by warning that the Volumetrics diet would not be suitable for athletes, anyone pregnant, or breastfeeding.

She warns against being drawn to fad diets that promise weight loss without considering their effect on your overall health. While it may sound straightforward, the Volumetrics diet has not been extensively researched for its long-term clinical health outcomes.

“For example, there is so much research around the Mediterranean diet being one of the healthiest diets in the world," she says. “There is not a huge amount of research on the Volumetrics diet.”