Proper preparation for a fasting blood test is essential for accurate results and effective health assessment.
You’ve been told to “fast before your blood work.” Cool. But what exactly does that mean?
Can you drink coffee? What about water? Do supplements count? And how long is “fasting,” really?
At YFS (Your Form Sux), we don’t expect you to know all this stuff — we teach you. So here’s your quick, clear, no-B.S. guide to fasting for blood work, so you show up prepped, hydrated, and ready to get accurate results.
🕒 First: What Does “Fasting” Actually Mean?
Fasting for a blood test means no food or drink (other than water) for a set amount of time before your test — usually 8 to 12 hours.
It allows your body to return to a baseline state so we can measure:
- Glucose (blood sugar)
- Insulin
- Cholesterol and triglycerides
- Liver and kidney markers
- Inflammatory levels
If you eat or drink during that window, you can skew the results — and that throws off the whole plan.
✅ Do’s Before a Fasting Blood Test
1. Fast for 8–12 Hours
Most labs require at least 8 hours, with 10–12 hours being the sweet spot for things like insulin, glucose, and lipids.
That means:
If your test is at 8:00 AM → stop eating by 8:00–9:00 PM the night before.
2. Drink Water — Seriously, Don’t Skip This
Hydration helps with blood flow, vein visibility, and overall comfort during the draw. You CAN (and should) drink plain water during your fasting window.
What to avoid:
- Flavoured water
- Electrolyte mixes
- Lemon, stevia, or anything else that might mess with your metabolism
3. Take Medications (If Approved by Your Provider)
Most meds are okay to take, but always check with your functional provider or prescribing doctor.
If it’s a supplement, skip it. We want your natural baseline — not a boosted one.
4. Sleep Well the Night Before
Yes, poor sleep can affect things like cortisol, glucose, and insulin levels. Try to get 7–8 hours if you can — and avoid heavy meals, alcohol, or super late-night workouts the night before.
5. Bring a Snack for After
Once your blood’s drawn, have a light snack ready to go — something with protein, healthy fat, and a bit of carb. This prevents a post-fast blood sugar crash or dizziness.
Examples:
- Protein bar
- Handful of almonds + apple
- Greek yogurt
- Hard-boiled egg + toast
🚫 Don’ts Before a Fasting Blood Test
- ❌ Don’t drink coffee or tea: Not even black coffee. Caffeine can temporarily increase glucose, cortisol, and blood pressure.
- ❌ Don’t chew gum or suck on mints: Even sugar-free gum can trigger digestion and insulin release.
- ❌ Don’t work out that morning: Heavy training affects glucose, cortisol, creatine kinase, and inflammation markers.
- ❌ Don’t break the fast early: Even a splash of cream, a bite of banana, or your morning supplements can change the data.
Bonus Tip: Tell Your Provider If You Messed Up
If you accidentally ate or drank something, don’t fake it. Just be honest — we’ll either adjust the interpretation or reschedule the test. You’re not in trouble — but the data only helps you if it’s accurate.
The YFS Standard: Education Comes Before Everything
At Your Form Sux, we don’t just run labs — we translate them into a strategy. That means we care about:
- Accurate prep
- Clear explanations
- Thoughtful interpretation
- And a plan that actually makes sense for your goals
Whether we’re tracking inflammation, hormones, insulin, or recovery markers — clean data = better outcomes.
Need labs? Not sure what to test or how to prep?
Book a functional assessment at YFS — and we’ll guide you through every step, from bloodwork to movement to full-body optimization.
