Carbohydrates at night do not make you gain weight simply because they are eaten at night. The main driver of weight gain is total energy balance, not the time of day when macronutrients are consumed. Circadian biology is real and well documented: on average, the glycemic response to a meal is higher at dinner than at lunch. But for a healthy person without metabolic disorders, pasta at dinner is not the problem. No major nutrition authority — not the WHO, EFSA or Italy's 2024 LARN reference values — recommends restricting carbohydrates based on time of day.

Let us start with the question almost everyone has asked at least once: if I eat pasta or rice in the evening, will I gain more weight?

The short answer is no. The longer answer is: it depends what you mean by “more,” and it is worth understanding the distinction, because the version that circulates online is an oversimplification of what the science actually says.

The human body has an internal clock — what researchers call the circadian rhythm — that regulates dozens of biological functions over a twenty-four-hour period: sleep, body temperature, hormone production and also the way nutrients are handled. This clock is real and well documented. In the morning, the body is generally more efficient at handling carbohydrates: insulin sensitivity is higher, digestion generates more heat and metabolic processes are running at full pace. In the evening, these mechanisms slow down. The glycemic response to the same meal — how much blood glucose rises after eating — is on average higher at dinner than at lunch, and the body expends slightly less energy on digestion.

Up to this point, someone who says “carbohydrates at night are worse for you” is pointing to a real biological effect. The problem is the leap that comes next.

Because the path from biology to real-world changes in body weight is not as direct as it sounds. The main driver of weight gain is total energy balance: how much energy you consume over the course of the day compared with how much you use. This is supported by decades of research and by meta-analyses — studies that combine and analyze the results of many other studies — and it is one of the areas where high-quality scientific evidence is most consistent. If you consume more energy than you expend, over time you gain weight. If you consume less, you lose it. The timing of those calories is secondary compared with the total amount.

Trials on so-called time-restricted eating — concentrating meals within a limited daily eating window, a practice that has become very popular in recent years — point in the same direction. When researchers control total calorie intake, differences in weight linked solely to meal timing tend to be small. The main reason people often lose weight on these approaches is not that they eat at a particular hour. It is that by compressing meals into fewer hours, they often end up eating less overall.

That said, there are situations in which carbohydrate timing genuinely matters, and they are worth naming because they are real.

People with type 2 diabetes or insulin resistance — a condition in which cells respond less effectively to insulin — can benefit from paying closer attention to how carbohydrates are distributed throughout the day, with less concentrated intake in the evening. In these cases, timing can have a documented clinical effect on blood glucose and metabolic risk markers. But that is a specific medical situation, not a rule for the healthy general population.

Night-shift workers are in a different situation. Eating during the “biological night” — when the body's internal clock expects sleep — is associated with higher metabolic risk independently of calories. Again, this is real, but it concerns a specific context, not someone who works during the day and eats pasta at eight in the evening.

For people who train, evening carbohydrates are often recommended rather than discouraged. If you exercise in the late afternoon or evening, carbohydrates after training help replenish muscle glycogen stores. In that context, evening is an appropriate time to eat them, not the wrong one.

The main nutrition authorities — the World Health Organization, EFSA, the European Food Safety Authority, and Italy's LARN nutrient reference values updated in 2024 — do not contain recommendations about what time of day carbohydrates should be eaten. Their guidance focuses on quality, such as preferring whole grains to refined ones and limiting free sugars, on total quantity and on overall balance. “Do not eat carbohydrates at night” is not an institutional recommendation. It is an idea that came from somewhere else.

And the Mediterranean diet? It has never contained that restriction. Pasta, legumes, bread and rice have been eaten at dinner for generations — in the Cilento families Ancel Keys studied in the 1950s, in Puglian kitchens and across Mediterranean tables. The dietary pattern validated by research does not remove carbohydrates in the evening. It distributes food sources sensibly across the day, prioritizes quality and leaves room for the wider context of the meal — including eating together and without rushing — to matter too.

So yes: circadian biology exists, time of day has a modest influence on metabolism, and there are specific conditions in which timing matters. But for a healthy person without metabolic disorders who eats a reasonably balanced diet, pasta at dinner is not the problem. Chronic excess energy intake is — and that can happen at any hour.