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Weight Loss Plateau? Blood Tests That Reveal Hidden Blockers
When the scale won't budge, your bloodwork often explains what your habits can't.
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Basic panels from $65.95 ($52.76 with the 20% code); comprehensive options up to $438.95 ($351.16 with code), promotional pricing at time of writing.
At a glance
When weight loss stalls despite consistent diet and exercise, blood testing checks the markers most often involved: fasting glucose, hemoglobin A1c, and insulin; thyroid hormones (TSH, Free T3, Free T4); cortisol; vitamin D, B12, and iron status; and hs-CRP for low-grade inflammation. This kind of panel is for people troubleshooting a plateau or rebound weight gain who want objective data to bring to their doctor. Panels can be ordered online with a doctor's order included, no separate appointment required.
Best suited for
- People who have stopped losing weight despite unchanged diet and training
- Anyone regaining weight after a successful cut and wanting to understand why
- Dieters with fatigue, cravings, or poor recovery alongside stalled progress
- Those who want lab numbers in hand before their next doctor's appointment
- People deciding whether to adjust nutrition, training, sleep, or supplements next
What's included
Weight Management (Women) - Basic
4 tests, 64 biomarkers
Weight Management (Men) - Basic
4 tests, 64 biomarkers
Weight Management (Women) - Basic Plus
11 tests, 71 biomarkers
Weight Management (Men) - Basic Plus
11 tests, 71 biomarkers
Weight Management (Women) - Advanced
18 tests, 82 biomarkers
Weight Management (Men) - Advanced
17 tests, 81 biomarkers
Weight Management (Women) - Comprehensive
22 tests, 86 biomarkers
Weight Management (Men) - Comprehensive
21 tests, 85 biomarkers
Weight Management Blood Test Panel, Women
12 tests, 48 biomarkers
Weight Management Blood Test Panel, Men
12 tests, 48 biomarkers
Deep-dive the key markers: Fasting Glucose, HbA1c, Fasting Insulin, LDL-C, HDL-C, Triglycerides, hs-CRP, TSH, Free T3, Free T4, Vitamin D, Ferritin, eGFR, ALT
Key biomarker ranges
Commonly used adult reference ranges for markers this panel measures, labs vary, so always interpret results against your lab's stated ranges and with your doctor.
Commonly used reference ranges place fasting glucose at 70–99 mg/dL; results vary with sleep, stress, and recent illness, and labs differ slightly.
| Zone | Range |
|---|---|
| Low | 50–70 mg/dL |
| Optimal | 70–100 mg/dL |
| Prediabetic range | 100–126 mg/dL |
| Diabetic range | 126–160 mg/dL |
Commonly used reference ranges place HbA1c below 5.7%; conditions affecting red blood cells can skew results, so labs and clinicians interpret in context.
| Zone | Range |
|---|---|
| Optimal | 4–5.7 % |
| Prediabetic range | 5.7–6.5 % |
| Diabetic range | 6.5–10 % |
Commonly used reference ranges accept up to ~25 µIU/mL, but many clinicians view single-digit fasting insulin as the more informative target; assays vary by lab.
| Zone | Range |
|---|---|
| Low | 0–2 µIU/mL |
| Optimal | 2–10 µIU/mL |
| Above optimal | 10–25 µIU/mL |
| High | 25–30 µIU/mL |
The importance of testing
A plateau is frustrating precisely because effort and results stop matching. Bloodwork turns that frustration into a checklist: glucose, A1c, and fasting insulin show how your body is handling carbohydrates right now, and patterns in these markers are associated with insulin resistance, a common companion to stalled fat loss that calorie-counting alone won't reveal.
Hormonal context matters just as much. TSH, Free T3, and Free T4 track how the thyroid is regulating metabolic rate, and cortisol reflects accumulated stress and under-recovery, relevant when hard training plus aggressive dieting leaves you tired but not lighter. These are numbers worth reviewing with your doctor before concluding that more restriction is the answer.
Finally, nutrient and inflammation markers explain the energy side of the equation. Ferritin and iron studies relate to oxygen delivery and fatigue, vitamin D and B12 are tied to energy metabolism, and hs-CRP screens for low-grade inflammation associated with weight gain. Testing a baseline now and retesting after eight to twelve weeks of adjusted habits gives you and your clinician trend lines instead of guesses.
Promo code
ULTAE54BSave 20% with code ULTAE54B, limited-time promotion; confirm final pricing on the partner page.
Ready to get your numbers? Order online, visit a nearby draw site, and receive private results to review with your doctor.
Order NowFrequently asked questions
Which blood tests should I check when weight loss stalls?
The markers most often reviewed for a plateau are fasting glucose, hemoglobin A1c, and insulin; thyroid hormones (TSH, Free T3, Free T4); cortisol; vitamin D, B12, and iron studies including ferritin; a lipid panel; and hs-CRP. Weight management panels bundle these so you can establish a baseline in a single blood draw.
Can a blood test explain why I'm not losing weight?
It can flag measurable patterns that often accompany stalled progress, such as blood sugar and insulin trends, thyroid hormone levels, elevated cortisol, or low vitamin D and iron, but it is not intended to confirm any condition. The results give you and your doctor concrete starting points for adjusting nutrition, training, sleep, or supplementation.
Do I need a doctor's appointment to get tested?
No, a doctor's order is included with every purchase, and no insurance or appointment is required. You order online, walk in or schedule at one of roughly 2,100 Quest locations, and most physician-reviewed results arrive in your secure account within 24–48 hours.
How often should I retest during a weight loss plateau?
A common approach is to establish a baseline, make targeted changes, and retest after a few months to see how the markers trend, your doctor can advise the right interval for your situation. Trend data across two or more draws is generally more informative than any single result.
Is this testing available in every US state?
No, direct-to-consumer lab testing is restricted or prohibited in New York, New Jersey, and Rhode Island, so residents of those states may be blocked at the partner's checkout. Elsewhere, testing is available at Quest locations nationwide.
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