Could Your Neck Size Predict Diabetes or Heart Risk? Learn What the Studies ShowYour neck measurement can reveal hidden risk: a larger neck circumference has been associated with changes in blood sugar levels and early signs of diabetes, and predicts a higher risk of type 2 diabetes in population studies.[1]

It is also linked to future heart disease and broader cardiovascular disease, often together with high cholesterol and LDL cholesterol, high markers that raise the chance of serious heart problems. [2]

How to Measure Your Neck Accurately

1. Use a soft measuring tape.
2. Stand upright, shoulders relaxed, head in a neutral Frankfurt plane.
3. Wrap the tape horizontally just below the Adam’s apple (thyroid cartilage), perpendicular to the neck’s long axis. [14]
4. Keep the tape snug (firm contact) without compression.
5. Take the measurement at the end of a normal breath.
6. Repeat twice and record the average for consistency.

What Counts as a High Neck Circumference?

There isn’t a single “normal” neck circumference. Values that flag risk differ by purpose and population. For quick screening of obstructive sleep apnea, a practical cutoff of >40 cm is commonly used in adults. For cardiometabolic risk, studies often report approximate ranges of ~38–40 cm in men and ~33–35 cm in women (population-specific). Treat these as screening ranges, not diagnoses.

What a larger neck might mean (simple, research-backed)

The Next-Level Metric: Neck-to-Height Ratio (NHtR)

What is NHtR? Neck Circumference (cm) ÷ Height (cm).

Why it helps: It scales neck size to your body frame, improving detection of upper-body adiposity and related metabolic risk.

Key finding: Recent population data link NHtR ≈ 0.215 (21.5%) to higher risk of MASLD (metabolic dysfunction-associated steatotic liver disease).[15] Published cutoffs generally fall within ~0.21–0.224, with some studies proposing sex-specific thresholds (e.g., around ~0.224 in men and ~0.208 in women).

How to use it (practical):
- If your NHtR is ~0.21 or higher, discuss metabolic screening (glucose, HbA1c, lipids, liver enzymes) with your clinician.
- Treat NHtR as a screening tool, not a diagnosis; interpret alongside waist, BMI, blood pressure, and clinical context.

• A sign of upper-body fat and metabolic risk. A larger neck circumference often reflects extra fat in the upper body and is linked with higher cardiometabolic risk in population studies. [3]
• Higher chance of developing type 2 diabetes. People with greater neck measurements have been shown to have higher fasting glucose and a higher incidence of type 2 diabetes in prospective studies. [4]
• Associated with unhealthy cholesterol and heart risk. Larger neck size correlates with adverse lipid patterns and is associated in some cohorts with increased risk of cardiovascular events. [4]
• A predictor of sleep apnea, which stresses the heart. Neck circumference is one of the best simple measures that predict obstructive sleep apnea; untreated sleep apnea raises blood pressure and cardiac strain. [5]
• Sometimes not metabolic — check structural causes. A clearly asymmetric or rapidly growing neck may be due to thyroid enlargement (goiter) or rare fat-deposition disorders and needs clinical evaluation. [6]
• Why Your Neck Size Might Change: A larger neck can result from muscle growth, higher testosterone, or natural build—but sudden or uneven changes may signal thyroid issues or fat buildup linked to insulin resistance.

Health Screening Tests

• Fasting blood sugar (glucose) & HbA1c — These tests check how your body handles sugar over time and assess your risk for type 2 diabetes. [13]
• Lipid profile — This panel measures total cholesterol, LDL (“bad” cholesterol), HDL (“good” cholesterol), and triglycerides to evaluate your risk for heart disease and cardiovascular problems.
• Thyroid function tests (TSH, Free T4, sometimes Free T3 and antibodies) — These help determine if an enlarged neck is due to thyroid gland issues such as an underactive or overactive thyroid, or a goiter. [7]
• Neck-specific examination and possibly ultrasound — If your neck size has increased rapidly, is asymmetric, or is associated with symptoms like difficulty swallowing, hoarseness, or breathing issues, an ultrasound or referral to an ENT/Endocrine specialist may be required to assess structural causes (e.g., nodules or thyroid enlargement). [8]

When to Seek Medical Evaluation

See your clinician if neck size increases rapidly, appears asymmetric or firm, or you develop snoring, choking at night, hoarseness, trouble swallowing, or breathing issues. If NHtR is ~0.21 or higher or neck circumference is large, ask about fasting glucose, HbA1c, lipid profile, and liver assessment. Follow age-appropriate national cancer screening separately in a dedicated guide.
 

Note on general cancer screening (unrelated to neck size)

Follow your country’s age-appropriate cancer screening with your clinician (e.g., breast, cervical, colorectal, lung, prostate, skin). This is separate from neck circumference and NHtR. See national guidelines such as the American Cancer Society [9,10] and the National Cancer Institute [11 ,12] for details

FAQ

What neck circumference is high risk for sleep apnea?
A practical adult screening cutoff is >40 cm; diagnosis still requires clinical testing.

What NHtR indicates fatty liver risk?
Around 0.215 is a useful signal, with published ranges ~0.21–0.224. Use it as a screening metric alongside other measures.

Does neck size alone predict diabetes or heart disease? 
No. Larger NC/NHtR are associated with higher risk, but clinicians confirm risk with glucose, lipids, blood pressure, liver markers, and sleep apnea testing.

Conclusion

The diagnostic tests described above offer a roadmap for detecting early signs of metabolic or structural disorders. However, normal ranges are guideposts—not guarantees. If you notice any neck enlargement, asymmetry, firmness, or related symptoms (e.g. difficulty swallowing, hoarseness, or new snoring), it is critical to consult your physician promptly and undergo any additional tests they recommend. Use these tests as tools—not as a substitute—for professional medical evaluation and care.

Resources

1. Association between neck circumference and diabetes mellitus: a systematic review and meta-analysis ,doi: 10.1186/s13098-023-01111-z ,PMC PubMed Central
2. The association of neck circumference with risk of metabolic syndrome and its components in adults: A systematic review and meta-analysis , pure.johnshopkins.edu
3. Neck circumference and its association with cardiometabolic risk factors: a systematic review and meta-analysis , doi: 10.1186/s13098-018-0373-y , PMC PubMed Central
4. Neck Circumference and Incidence of Diabetes Mellitus over 10 Years in the Korean Genome and Epidemiology Study (KoGES) , nature.com
5. Neck Circumference-Height Ratio as a Predictor of Sleep Related Breathing Disorder in Children and Adults , doi: 10.5664/jcsm.5572 , PMC PubMed Central
6. Goiter , mayoclinic.org
7. Thyroid Tests , clevelandclinic.org
8. Management of THYROID DISORDERS , moh.gov.my
9. American Cancer Society Guidelines for the Early Detection of Cancer , cancer.org
10. Screening Tests , cancer.gov
11. Cancer Screening Guidelines by Age , cancer.org
12. General Cancer Screening Guidelines , clevelandclinic.org
13. Cut-off points of neck and waist circumference as predictors of obstructive sleep apnea in the Colombian population: a comparison with polysomnography , doi: 10.1590/1516-3180.2022.0415.R2.310523 , PMC PubMed Central
14. Neck Circumference , .sciencedirect.com
15. Assessment of neck to height ratio as a predictive tool for metabolic dysfunction-associated steatotic liver disease in Korean adults: a cross-sectional analysis from Korea National Health and Nutrition Examination Survey 2019–2021 , www.kjfm.or.kr

Last updated or reviewed on November 09, 2025

How we reviewed this article

Sources
Our experts continually monitor the health and wellness space, and we update articles when new information becomes available.
Current Version
October 25, 2025
Written By
Nour Hany
Edited By
KirolosReda
Medically Reviewed By
Dr. Ahmed Mostafa Mostafa