Table 2.

Dietary patterns impacting the biological clock.

Caloric restriction, a dietary regimen with 20–40% daily calorie intake decrease, whilst maintaining meal frequency to avoid malnutrition or essential nutrients deficiency.

High-fat diet, a diet regimen containing a higher percentage of fat (≥45% energy by fat) with respect to a normal diet (≤10% fat).

Fasting mimicking diet, a plant-based diet program planned to accomplish fasting-like effects while supplying micronutrient nourishment (vitamins, minerals, etc.), whilst reducing the challenge of fasting. It consists of proprietary vegetable-based soups, energy bars, energy drinks, chip snacks, chamomile flower tea, and a vegetable supplement formula tablet; the diet program consists of a 5 day regimen: day 1 of the diet supplies 1.090 kcal (10% protein, 56% fat, 34% carbohydrate), days 2–5 are identical in formulation and provide 725 kcal (9% protein, 44% fat, 47% carbohydrate).

Intermittent fasting, consumption of water exclusively or very low calorie (~500 kcal/die) diet for less than 24 h followed by normal feeding for 1–2 days.

Periodic fasting, a dietary pattern entailing 2 or more days of no food consumption repeated after no <1 week of regular feeding.

Time restricted feeding, a daily eating pattern in which all nutrient intake occurs within a few hours (usually <12 h) every day, with no overt attempt to alter quantities, proportions, variety, or combination of different foods, drinks, and nutrients.

Ketogenic diet, a high-fat diet with sufficient protein and very-low-carbohydrate intake triggering a switch to fatty acid β-oxidation as an energy source.