Two Body Fats With Very Different Health Effects
Body fat is often discussed as a single entity, but the type and location of fat profoundly affect health. Subcutaneous fat — the fat just under your skin — is largely metabolically benign. Visceral fat — the fat surrounding internal organs — is metabolically active in harmful ways and drives much of the cardiovascular and metabolic disease associated with obesity.
Two patients can have identical weights and identical BMIs but very different health risks based on where their fat sits. Understanding visceral fat helps explain why some "thin" people develop metabolic disease while some larger people remain metabolically healthy.
At Zimmer Medical Group, we focus on body composition and metabolic health, not just weight, when assessing cardiovascular risk and treatment goals.
Why Visceral Fat Matters
Visceral fat behaves differently from subcutaneous fat:
- Releases inflammatory cytokines that drive systemic inflammation
- Releases free fatty acids directly into the portal circulation, affecting liver metabolism
- Contributes to insulin resistance and metabolic syndrome
- Drives the development of non-alcoholic fatty liver disease (now called MASLD)
- Increases cardiovascular disease risk independently of total body weight
- Contributes to type 2 diabetes risk
- Associated with increased cancer risk
- Affects hormone balance
The metabolically active nature of visceral fat means that even modest reductions can significantly improve cardiovascular and metabolic risk markers.
The Difference Between Body Types
Two general body fat distributions:
Apple-Shaped (Android Distribution)
- Fat concentrated in abdomen and trunk
- More visceral fat
- Higher cardiovascular and metabolic risk
- More common in men, but increasing in postmenopausal women
- Often associated with insulin resistance
Pear-Shaped (Gynoid Distribution)
- Fat concentrated in hips and thighs
- More subcutaneous fat
- Lower metabolic risk for the same total body weight
- More common in pre-menopausal women
- Subcutaneous lower-body fat may even be protective
A man with significant abdominal fat at a "normal" BMI of 24 may have higher metabolic risk than a woman with primarily lower-body fat at a BMI of 28.
How to Measure Visceral Fat
Practical Office Measures
Waist circumference:
- Measured at the level of the belly button after gentle exhalation
- Higher risk thresholds:
- Men: > 40 inches (102 cm)
- Women: > 35 inches (88 cm)
- For Asian populations, lower thresholds apply
Waist-to-hip ratio:
- Waist measurement divided by hip measurement
- Higher risk: > 0.9 in men, > 0.85 in women
Waist-to-height ratio:
- Waist circumference divided by height (same units)
- Goal: < 0.5
- Simple "Keep your waist less than half your height" message
These simple measurements often predict cardiovascular and metabolic risk better than BMI alone.
More Sophisticated Measures
- DEXA scan — provides body composition including visceral fat estimate
- CT or MRI — gold standard for measuring visceral fat (used in research; not for routine clinical care)
- Bioelectrical impedance scales — variable accuracy; helpful for tracking trends if same scale used consistently
Who Has More Visceral Fat
Risk factors for higher visceral fat:
- Older age
- Male sex (women catch up after menopause)
- Family history
- Genetic factors (some ethnic groups have more visceral fat at lower BMI)
- Excess calorie intake
- High refined carbohydrate intake
- Sedentary lifestyle
- Sleep deprivation
- Chronic stress (cortisol drives visceral fat accumulation)
- Excessive alcohol intake
- Smoking
- Certain medications (chronic steroids, some antipsychotics)
- Hormonal changes (menopause, low testosterone in men)
What Reduces Visceral Fat
Good news: visceral fat is more responsive to lifestyle changes than subcutaneous fat. Patients often lose visceral fat preferentially with weight loss, even when subcutaneous fat changes less.
1. Caloric Reduction with Quality Choices
Weight loss reduces visceral fat. Even modest weight loss (5–10 percent of body weight) significantly reduces visceral fat and improves metabolic markers.
The composition of weight loss matters:
- Mediterranean and similar dietary patterns associated with greater visceral fat reduction — see our Mediterranean diet article
- Low-refined-carbohydrate approaches preferentially reduce visceral fat in some patients
- Adequate protein intake preserves muscle during weight loss — see sarcopenia
- Whole foods over processed
- Reduce sugar-sweetened beverages
2. Exercise — Particularly Aerobic Plus Resistance
Both types help, but evidence is particularly strong for combined approaches:
- 150+ minutes per week of moderate aerobic activity
- Resistance training 2–3 times weekly
- Higher-intensity exercise (when appropriate) reduces visceral fat efficiently
- Even without weight loss, regular exercise reduces visceral fat
Aerobic exercise alone reduces visceral fat. Resistance training adds muscle, supporting metabolism. The combination is most effective.
3. Sleep Optimization
- Inadequate sleep increases visceral fat accumulation
- 7–9 hours per night for most adults
- Treat sleep apnea when present
- Address sleep hygiene
4. Stress Management
- Chronic stress and cortisol promote visceral fat storage
- Mindfulness, meditation, yoga, and other stress-reduction approaches help
- Address sources of chronic stress when possible
5. Limit Alcohol
- Alcohol calories preferentially deposit as visceral fat
- Reducing intake often produces visible abdominal fat reduction
6. Medications When Appropriate
- GLP-1 receptor agonists (semaglutide, tirzepatide, liraglutide) — see our GLP-1 medications article — preferentially reduce visceral fat
- SGLT2 inhibitors — also reduce visceral fat
- Metformin — modest effect on visceral fat
- Bariatric surgery — substantial visceral fat reduction with sustained weight loss
What Doesn't Work (Or Works Less)
- Spot reduction — abdominal exercises don't preferentially reduce abdominal fat
- Crash diets without exercise often lose muscle along with fat
- "Detox" cleanses — no impact on visceral fat
- Most "fat-burning" supplements — minimal evidence
- Waist trainers and similar garments — temporary appearance change only
Special Considerations
Postmenopausal Women
Estrogen loss after menopause shifts fat distribution toward the abdomen. Women may notice increasing waist circumference even without significant weight gain. Strategies:
- Maintain or increase strength training
- Adequate protein intake
- Address sleep changes during perimenopause
- Mediterranean-style eating
Men with Low Testosterone
Low testosterone is associated with increased visceral fat. The relationship goes both ways: visceral fat lowers testosterone, and low testosterone promotes visceral fat. Address both — see low testosterone.
Patients with NAFLD/MASLD
Reducing visceral fat is the single most effective treatment for fatty liver disease. Even 7–10 percent weight loss often reverses significant disease.
Realistic Expectations
- Visceral fat decreases occur within weeks of consistent lifestyle changes
- Substantial visible improvement typically takes months
- Cardiovascular risk markers (blood pressure, lipids, insulin resistance, inflammation) often improve before visible changes
- Sustainable, gradual changes work better than aggressive short-term interventions
When to See Your Doctor
- Concerning waist circumference (above thresholds listed above)
- Family history of metabolic syndrome, diabetes, cardiovascular disease
- Difficulty losing abdominal fat despite reasonable efforts
- New abdominal weight gain
- Signs of metabolic syndrome (high blood pressure, high glucose, high triglycerides, low HDL)
- Considering medications or other intervention for weight management
The American Heart Association and American Diabetes Association provide additional resources on body composition and metabolic health.
Concerned about abdominal fat or metabolic risk? Contact Zimmer Medical Group for a comprehensive metabolic assessment and a personalized plan that targets visceral fat — including medications when appropriate.
