Chrononutrition

Presentation

Chrononutrition is a nutritional method conceptualized by Dr. Alain Delabos in 1986, in collaboration with Prof. Jean-Robert Rapin. It rests on the principle that nutrition effectiveness depends not only on what we eat but also when we eat it. Enzymatic and hormonal secretions follow a precise circadian rhythm that conditions the body's ability to metabolize different macronutrients.

Chronobiological Principles

In the morning, cortisol peaks (7-8 AM), stimulating gluconeogenesis and lipolysis. Lipases and proteases are active — optimal time for saturated fats and proteins. Midday, insulin and amylases reach maximum — time for proteins and complex carbohydrates. Afternoon (4-5 PM), a physiological insulin peak justifies a sweet snack. Evening, digestive secretions decrease significantly — meals should be light and low-calorie.

Typical Protocol

• Breakfast (7-8 AM): fatty meal — aged cheese, whole grain bread, butter, unsweetened hot drink
• Lunch (12-1 PM): dense meal — animal or plant proteins, whole grain starches, green vegetables
• Snack (4-5 PM): natural sweet — dark chocolate 70% or fresh fruits or nuts
• Dinner (7-8 PM): light meal — lean fish or seafood, cooked or raw vegetables

Scientific Basis

Nutritional chronobiology is an expanding research field. Studies confirm that the same calories consumed morning or evening have different metabolic impacts. Garaulet et al. (2013) showed late lunchers lost significantly less weight. Research on time-restricted feeding confirms benefits of food synchronization on weight, blood sugar and inflammatory markers.