The Reality Check
Let's set expectations: Week 1 is not when the magic happens. Your starting dose (0.25mg semaglutide or 2.5mg tirzepatide) is deliberately sub-therapeutic. It's designed to let your body adjust—not to produce dramatic weight loss.
Some people feel effects immediately. Others feel nothing at all. Both are normal. Here's what to actually expect.
Day by Day
Day 1: Injection Day
The needle is tiny—much smaller than you're imagining. Most people describe it as a brief pinch or nothing at all. Common injection sites: belly (most popular), thigh, or back of upper arm.
What you might feel: Maybe a little nervous energy. Possibly nothing at all. Any immediate sensation is usually psychological anticipation, not the medication working yet.
Days 2-3: The Waiting Game
The medication is entering your system, but effects are subtle. You might notice:
• Slightly less interest in snacking
• A vague sense of being "satisfied" more easily
• Or absolutely nothing—this is equally common
Don't panic if you feel no different. The first dose is intentionally weak.
Days 4-5: First Signs (Maybe)
If you're a "super responder," you might start noticing reduced appetite around now. Your portion sizes might naturally shrink. You might forget about food for longer stretches.
If you're not feeling anything yet, that's fine. Most people don't have significant effects at the starter dose.
Days 6-7: Assessment Time
Take stock: Any changes in hunger? Energy? Digestion? These observations will be useful when you talk to your provider about dose adjustments.
Weight: You might see a pound or two drop, mostly from eating less and water shifts. Don't obsess over the scale yet.
Side Effects You Might Experience
The starter dose minimizes side effects, but some people still experience:
Mild nausea: Usually comes in waves, often after eating too much or too fast. It's your body telling you to slow down.
Fatigue: Your body is adjusting to new hormonal signals. This typically passes within a few weeks.
Slight constipation: Slower digestion means slower bowel movements. Stay hydrated and consider adding fiber.
Injection site reactions: Minor redness or itching is normal and resolves quickly.
Pro tip: If you experience no side effects, don't worry that the medication "isn't working." No nausea is a win—it means your body is adjusting smoothly. Effects will build as you increase doses.
What to Eat (And Avoid)
Your old eating habits may not work anymore. GLP-1 slows your digestion, so large portions and heavy foods can make you feel awful. Here's the general approach:
Go for:
- Smaller portions than you think you need
- Protein-rich foods (you need protein to preserve muscle)
- Easily digestible options: chicken, fish, eggs, soft vegetables
- Plenty of water throughout the day
Avoid or reduce:
- Fried or greasy foods (big nausea triggers)
- Large portions of red meat
- Carbonated drinks
- Eating fast—slow down significantly
The golden rule: Stop eating before you feel full. Your "full" signals are delayed. If you eat until you feel satisfied, you've probably overeaten.
What NOT to Expect
- Dramatic weight loss: 1-2 lbs max in week 1, and some people see nothing.
- Complete appetite elimination: That comes later at higher doses (if at all).
- Instant energy: Some people feel tired at first while adjusting.
- Zero side effects: Possible, but don't be surprised by mild GI symptoms.
When to Contact Your Provider
Most first-week experiences are normal, but reach out if you have:
- Severe, persistent vomiting (can't keep liquids down)
- Intense abdominal pain that doesn't resolve
- Signs of allergic reaction (swelling, difficulty breathing)
- Any symptom that feels genuinely wrong, not just uncomfortable
Mild nausea and fatigue? Ride it out. It typically improves.
The Mindset Shift
Week 1 isn't about results—it's about building the foundation. Use this time to:
- Establish your injection routine
- Start tracking how foods make you feel
- Notice any changes in hunger or cravings
- Practice eating slowly and stopping before full
The medication works over months, not days. Trust the process. The real changes are coming.
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