Nutrition advice has a reputation for being complicated, contradictory, and constantly changing. One week fat is the enemy, the next it’s sugar. One study recommends a food, another contradicts it entirely. Two researchers at French institutions decided the entire approach was the problem – and built something different.
Why counting nutrients misses the point
Anthony Fardet, a researcher at the Human Nutrition Unit of the University of Clermont-Auvergne, and Edmond Rock, research director at the French National Research Institute for Agriculture, Food and Environment (INRAE), argue that focusing on individual nutrients – protein grams, vitamin percentages, calorie counts – is fundamentally insufficient as a guide to eating well. Their framework, published via The Conversation, is built on a different premise: that food quality matters more than food composition, and that the degree of processing is the variable most people are ignoring entirely.
The result is the 3V rule. Three criteria, applied in a specific order, designed to work as a practical decision-making tool at the point of purchase rather than a laboratory calculation.
What the three Vs actually mean
The first V stands for Vrai – real, or unprocessed. This is the foundation of the entire framework, and the researchers are explicit that it comes first for a reason. Before thinking about anything else, the priority is separating genuinely whole foods from ultra-processed products. Within the “real food” category, three additional sub-rules apply: favor whole grains over refined ones, choose solid forms over liquid ones, and keep added salt, sugar, and fat to a minimum.
The second V is Végétal – plant-based. Once the processing question is settled, the next consideration is the ratio of plant to animal foods in the diet. Shifting that ratio toward plants is the second lever.
The third V is Varié – varied. Dietary diversity, across both plant and animal foods that meet the first two criteria, is the final layer. Where possible, the researchers also recommend prioritizing organic, local, and seasonal options to reduce environmental impact and improve micronutrient density.
What the data shows in practice
The researchers applied the 3V framework to thirty years of dietary data from France and China. In France, as of 2015, ultra-processed foods accounted for around 46% of daily calories for children under 18, 35% for adults, and 27% for those over 65. An analysis of 708 regular shoppers across 122 hypermarkets found the average cart contained 61% ultra-processed calories and 41% animal-sourced calories – both far from 3V targets.
One finding from the French data stands out: a shopping cart that meets 3V criteria would cost approximately 5% less than the average cart, primarily by replacing ultra-processed animal calories with whole plant foods.
The Chinese data reinforces the core argument from a different angle. Between 1990 and 2019, total calorie intake in China fell by 9% and dietary variety improved – yet rates of obesity doubled and type 2 diabetes prevalence rose from 2% to 11%. The researchers point to the simultaneous rise in processed and animal-sourced calories as the more likely explanation, suggesting that meeting nutritional targets is not sufficient if the quality of the food matrix is deteriorating.
The bottom line
Real food first, more plants second, more variety third – in that order. The 3V rule doesn’t require calorie counting, supplement knowledge, or nutritional expertise. It requires one question asked at the supermarket before anything else: how processed is this? According to the researchers behind it, that single shift in how we evaluate food does more for long-term health than optimizing any individual nutrient ever could.