Read the guide · Nutrition
What Really Matters in Your Diet
There is a clear hierarchy: total energy and protein determine the outcome, food quality dictates how sustainable it is, and the rest is fine-tuning. Eating ultra-processed foods leads to eating more without realizing it; protein and foods that require chewing increase satiety; meal frequency and eating windows do not change weight on their own. Letz organizes targets in this order, and never sells meal timing as a method.
Numbers derived from this rule
| Parameter | Range | Weight | Rule |
|---|---|---|---|
| Fiber | 12–16 g per 1000 kcal | 50% | About 14 g of fiber per 1000 kcal, which amounts to 25 to 29 g per day for most adults.Fiber and Carbohydrate Quality · Ultra-Processed Foods Lead to Eating More |
| Protein meals per day | 3–5 meals | 40% | The number of meals does not affect weight; distributing protein across 3 to 5 meals improves its utilization.Distribute protein throughout the day · Nutrient timing and the anabolic window · Meal Frequency and Eating Window |
| Dietary fat | 20–35 % of calories | 50% | Fat between 20 and 35% of calories; below 20% impairs hormones and adherence.Calorie surplus for muscle gain · Carbohydrates and Workout Performance |
| Diet break after | 6–12 weeks in a deficit | 20% | After 6 to 12 weeks in a deficit, one or two weeks at maintenance reduce hunger and adaptation without gaining fat.Planned Diet Breaks · Weight Loss Maintenance and Metabolic Adaptation |
Rules and studies
- 01Ultra-Processed Foods Lead to Eating MoreWhen meals were matched for macronutrients, an ultra-processed diet led participants to eat roughly 500 kcal more per day and gain weight.The meal planner pantry classifies each food by its degree of processing (NOVA): whole foods form the base of meals, ultra-processed foods serve as complements, and photo logging flags when the day was dominated by them.
- 02Satiety: Protein and Eating SpeedHigher-protein diets reduce appetite and spontaneous intake; eating more slowly reduces the amount consumed in a meal.When logs indicate high hunger, the coach suggests adding protein and fiber to the next meal before cutting calories further.
- 03Meal Frequency and Eating WindowEating more or fewer times per day does not change weight loss when calories are equated; restricting the eating window helps only to the extent that it reduces intake.Letz lets users choose how many meals to eat and adjusts portions accordingly, distributing protein across 3 to 5 meals; it does not market fasting as a superior method.
- 04Nutrient timing and the anabolic windowTotal daily protein intake matters more than exact timing; the so-called anabolic window is broad, and consuming protein within a few hours around training is sufficient.The meal plan does not require an immediate shake; it schedules a meal with protein and carbohydrates near your workout and distributes the rest throughout the day.
- 05Carbohydrates and Workout PerformanceCarbohydrates sustain long, high-volume sessions; for short resistance training sessions, intake from the previous day is usually sufficient, and daily totals should match the training load.Carbohydrates serve as the adjustment macronutrient: they increase on training days and decrease on rest days while maintaining the weekly average.
- 06Hydration and ExerciseDehydration exceeding approximately 2% of body weight impairs performance; fluid requirements are individual and depend on sweat rate, climate, and duration.The Letz water target serves as a routine baseline and increases on training days; it is not treated as a prescription.
- 07Alcohol and muscle recoveryAlcohol after training reduced muscle protein synthesis even when protein was ingested alongside it.The coach does not forbid it; it contextualizes recovery and sleep readings on the days following reported consumption.
- 08Planned Diet BreaksInterspersing periods of calorie deficit with maintenance weeks can improve fat loss efficiency and reduce hunger, yielding a similar final outcome.After 6 to 12 weeks in a calorie deficit with declining adherence, the coach suggests a week at maintenance as a planned strategy, not a failure.