Glossary
Key terms from fasting, nutrition, and weight loss - defined clearly and linked to the topics they belong to.
A
Action Loop
This loop works because it removes complexity and keeps your focus on a few actions you can repeat every day. Fasting reduces overall intake…
Adaptation Phase
During this phase, progress slows as the body adjusts to recent changes. Hormones and energy use begin to stabilize at the new weight. This…
Autophagy
Autophagy is the body's way of cleaning up and recycling damaged cellular parts. It increases during fasting, especially as fasting duration…
B
Behavior Proof
Behavior proof is the opposite of motivation. Instead of trying to believe you can change before acting, you act first and let the evidence…
Boring Meal Strategy
Repeating the same meals removes the need to constantly decide what to eat. This reduces mental effort and limits opportunities for impulsiv…
C
Caloric Deficit
A caloric deficit forces the body to use stored energy to cover the gap between intake and demand. This is the only way fat loss occurs over…
Carbohydrates
Carbohydrates are the body's fastest source of energy and are stored as glycogen in muscles and the liver. When you eat carbs, glycogen leve…
Cognitive Load
High cognitive load makes it harder to stay consistent with any plan. Too many decisions about food or routines can lead to fatigue. Simplif…
Cortisol
Cortisol rises when the body is under stress, including lack of sleep or heavy restriction. Higher levels can lead to temporary water retent…
D
Decision Collapse
Simplifying decisions reduces the need for willpower throughout the day. Instead of negotiating with yourself about food, you follow a clear…
Decision Fatigue
Every food decision — what to eat, how much, whether to have a snack, whether to log it — costs mental energy. By the end of the day, the ca…
Defended Weight
The body often settles into certain weight ranges where it feels stable. Leaving this range can require more consistency and patience. Progr…
Digestive Stagnation
Slow digestion can cause discomfort and make weight changes harder to interpret. Low fiber intake is a common cause, especially during restr…
Drift
Drift is more dangerous than a single bad day because it is invisible. There is no dramatic failure to react to — just a slow slide back tow…
E
Eating Window
The eating window gives structure to your day and removes constant decisions about when to eat. Instead of spreading food across many hours,…
Economy Mode
When calorie intake stays low for a long time, the body may reduce how much energy it uses. This slows down weight loss even if you continue…
Environment Design
Your surroundings shape your behavior more than motivation does. Keeping certain foods out of sight or out of the house reduces the chance o…
F
Fasting Arc
A fast usually follows a pattern where hunger rises, settles, and then becomes more stable. Early hours can feel easy, followed by a more di…
Fasting Window
The fasting window is where most of the metabolic change happens. During this time, insulin drops and the body begins to rely more on stored…
Fat
Fat is energy-dense, so small portions can contain a large number of calories. It does not create strong immediate signals of fullness for m…
Fat Oxidation
Fat oxidation increases when insulin levels are lower and glycogen stores are reduced. This happens during fasting or when food intake is co…
Fat-adapted State
As your body adapts to fasting, it becomes more efficient at using fat for energy. This reduces sudden hunger swings and makes longer fastin…
Fat-Burning Switch
When stored carbohydrates run low, the body begins to rely more heavily on fat for energy. This shift is gradual and depends on how long you…
Fatigue
Fatigue can build up when dieting, fasting, or training without enough recovery. It reduces motivation and makes simple decisions feel harde…
Feedback Loops
Your habits create loops where actions influence future behavior. Consistent routines make it easier to repeat the same actions again. Negat…
Food Ecosystem
Your food ecosystem is the set of meals and habits you return to regularly. It shapes how easy or difficult it is to stay consistent. A stab…
Food Environment
What you see and have access to strongly affects what you eat. Visible and easy-to-reach foods are more likely to be consumed without much t…
Food Mass Effect
The scale reflects everything inside your body, not just fat. After a large meal, weight can increase simply because of the food and water y…
Food-recognition Technologies
These tools attempt to estimate calories and nutrients from images of food. While they can be helpful, they are not always accurate in real…
Friction Removal
Reducing friction makes it easier to follow your plan without relying on motivation. This can include simplifying meals, preparing food in a…
G
Glycogen
Glycogen acts as a short-term energy reserve that the body can access quickly. It is stored with water, which affects body weight on the sca…
Glycogen Depletion
As glycogen is used for energy, the body begins to shift toward using fat. This process is a key step in fasting and calorie control. It is…
Glycogen Refill
After eating carbohydrates, glycogen stores are replenished in the body. This process brings water back into the muscles and liver. As a res…
Gut Reactivation
After a fast, your digestive system needs time to adjust to food again. Starting with lighter meals can help avoid discomfort and support a…
H
Habit Hunger
Habit hunger appears at times when you usually eat, even if your body does not need energy. It often fades if you wait or shift your attenti…
Holding Pattern
Weight can stay stable for a period even when your routine is consistent. This is often part of the normal pattern of weight loss. Internal…
I
Insulin Response
Insulin helps move nutrients into cells after eating. Larger responses often occur after carbohydrate-rich meals. This can influence hunger,…
Insulin Sensitivity
When insulin sensitivity is higher, the body handles nutrients more efficiently after eating. This can improve how energy is stored and used…
K
M
Macronutrients
Each macronutrient plays a different role in how your body responds to food. Protein supports fullness and helps maintain muscle. Carbohydra…
Maintenance
Maintenance is the point where your body weight stays relatively stable over time. Intake matches what your body uses for daily activity and…
Maintenance Boundary
This is the point where your intake matches what your body uses. Progress slows because there is no longer a consistent deficit. Small adjus…
Maintenance Mode
Maintenance mode is where you focus on keeping results stable rather than pushing further loss. Habits become more important than strict con…
Marginal Deficit
A marginal deficit creates slower but more controlled weight loss. It is easier to sustain because it does not require large restrictions. P…
Measurement Lag
Fat loss does not always show up on the scale right away. The body can hold onto water for days or weeks while fat is being reduced. This cr…
Metabolic Adaptation
Over time, the body can adjust to lower calorie intake by using less energy. This slows down weight loss even if you continue the same plan.…
Metabolic Switch
This switch happens when glycogen stores are reduced and the body needs another fuel source. The timing varies depending on your eating habi…
Momentum Window
After a fast, the body does not immediately return to its previous state. Hunger often stays lower for a short period, and energy use remain…
Monday Restart Loop
The Monday restart loop is one of the most common patterns in weight loss. It feels productive because each restart comes with genuine motiv…
N
O
P
Pattern Break
In FastNow, the primary pattern break is the 60-hour extended fast in Phase 1. By removing all food decisions for a defined period, it inter…
Plateau
A plateau is a normal part of the weight loss process. The body may hold water or adjust energy use, which slows visible progress. This does…
Protein
Protein helps you feel full and reduces overall food intake. It also supports muscle maintenance during weight loss. Including enough protei…
Protein Leverage
Prioritizing protein often leads to lower total calorie intake without strict control. Protein increases satiety and reduces the urge to sna…
R
Rebound Effect
Weight regain often happens when old habits return after a diet ends. The body also restores glycogen and water, which can increase weight q…
Rebound Weight
After eating again, weight often increases due to food, water, and glycogen returning. This change happens quickly and can feel discouraging…
Recovery Skill
Most people focus on preventing mistakes. But mistakes are inevitable — a missed fast, an untracked day, a weekend that went sideways. What…
Refeed
Refeeding is where you return to eating and restore energy levels. Glycogen stores refill and water comes back with them, which can increase…
S
Safe Foods
Safe foods are the meals you can rely on without losing control. They are usually simple, familiar, and easy to portion without guesswork. B…
Satiety
Satiety determines how long you can go without thinking about food. Foods that are high in protein or volume tend to increase this feeling.…
Scale Volatility
Daily weight changes are normal and often unrelated to fat. Water balance, food intake, and hormones can all affect the number. These fluctu…
Second Night Effect
This phase often appears during longer fasts and can feel uncomfortable. Sleep may be lighter and hunger signals can feel stronger than usua…
Soft Landing
A soft landing helps you move out of weight loss without sudden changes. Intake is increased gradually while keeping structure in place. Thi…
Spike-crash-crave Pattern
This pattern often follows meals high in refined carbohydrates. Blood sugar rises quickly, then drops, which can trigger hunger again. This…
Structure Over Willpower
Willpower is real but limited — it depletes throughout the day and fails under stress, fatigue, or emotional load. Structure (fixed meal tim…
Subconscious Program
Many eating behaviors happen automatically without active decision-making. These patterns are built over time through repetition and environ…
T
Total Daily Energy Expenditure
TDEE includes basic body functions, daily movement, and exercise. It changes over time as your weight and activity level change. Knowing you…
Trigger Foods
Trigger foods are the ones that make it hard to stop once you start eating. They are often highly rewarding and easy to consume quickly, whi…
True Hunger
True hunger builds slowly and feels steady rather than urgent. It does not depend on time of day or specific cravings. When you eat in respo…
W
Water Fast
A water fast removes all calories and forces the body to rely fully on stored energy. This can accelerate fat use but also increases physica…
Water Fasting
Water fasting removes all calorie intake and forces the body to rely entirely on stored energy. This increases fat use but also requires car…
Water Fluctuations
Water levels in the body can change quickly based on food, salt, and activity. These changes can move the scale by several pounds in a short…
Water Retention
The body can hold onto water in response to stress, food choices, or hormonal changes. This can make weight loss appear slower than it is. W…
Water Weight
Water weight can change quickly and is influenced by many daily factors. It can increase or decrease without any change in body fat. This ma…
Weight Floor
A weight floor is a period where the body holds a certain level before moving lower. Progress may pause while internal adjustments take plac…
Weight Regain
After weight loss, some regain is normal due to food intake and water returning. This can happen quickly and may feel discouraging. It does…
Whoosh Effect
The whoosh effect describes a sudden drop after a period of little change. The body releases retained water, which reveals earlier fat loss.…