Burning Belly Fat

What is belly fat, actually?

Belly fat is not a homogeneous mass. It consists of two compartments with fundamentally different properties: subcutaneous fat (directly under the skin) and visceral fat (around the organs in the abdominal cavity).

Subcutaneous fat is what you can grab. It is relatively metabolically inactive and cosmetically bothersome, but health-neutral in normal amounts. Visceral fat, on the other hand, surrounds the liver, intestines and pancreas. It produces inflammatory substances and hormones that pass directly via the portal vein to the liver.

You cannot see visceral fat — a normal BMI with a lot of visceral fat exists (TOFI: thin outside, fat inside). Men with a flat stomach can still have dangerously high amounts of internal fat.

Why is visceral fat dangerous?

Visceral fat tissue is endocrinologically active: it produces adipokines and inflammatory substances (TNF-alpha, IL-6), and disrupts insulin sensitivity. A lot of visceral fat is a direct driver of metabolic syndrome.

Proven increased risk with a lot of visceral fat: type 2 diabetes (2 to 5 times), cardiovascular disease (3 to 4 times), fatty liver disease (MASLD), certain cancers (colon, breast, uterus), sleep apnoea and early dementia.

The good news: visceral fat responds surprisingly quickly to weight loss. As little as 5 percent overall weight loss reduces visceral fat by 20 to 30 percent — more than subcutaneous fat. This substantially lowers the risks mentioned above.

Belly fat in women versus men

Sex hormones determine where you store fat. In women of reproductive age, oestrogen drives peripheral storage (hips, buttocks, thighs — 'pear shape'). In men, androgens dominate: fat accumulates centrally around the abdomen ('apple shape').

For women this changes drastically during menopause. Declining oestrogen shifts storage to the abdomen. Many women report a sudden 'menopause belly' between the ages of 45 and 55 despite the same lifestyle. This is physiologically normal, but does carry an increased metabolic risk.

Practical consequences: women after menopause need targeted intervention (strength, protein, possibly a discussion about HRT). Men should be alert to waist size from the age of 30-35. For both sexes: waist circumference is a better predictor than BMI.

Measuring belly fat — waist circumference and more

Measure your waist circumference at the narrowest point between the lowest rib and the top of the hip bone, breathing out in a relaxed way, not holding your stomach in. Do not measure at the navel — that is not a consistent reference point.

• Women: healthy <80 cm, increased risk 80-88 cm, strongly increased risk >88 cm.
• Men: healthy <94 cm, increased risk 94-102 cm, strongly increased risk >102 cm.
• Waist-to-hip ratio (waist divided by hip): women <0.85, men <0.95.
• Waist-to-height ratio (all ages, all sexes): <0.5 is healthy.
• For visceral fat specifically: a DEXA scan or MRI is the gold standard, but unnecessary for most people.

What does NOT work (but is sold anyway)

Much of the marketing around belly fat is nonsense. A short list of what is NOT evidence-based for targeted belly fat loss:

• Sit-ups, planks, crunches alone — strengthen the core but do not burn fat.
• Waist belts, 'fat burners', detox teas, slimming pills without GLP-1.
• Sauna and 'sweating it out' — you lose fluid, not fat.
• Spot-reduction laser or cryolipolysis — limited cosmetic effect on subcutaneous fat, nothing on visceral fat.
• Spot reduction via massage or vibration machines.
• One-meal-a-day or strict fasting patterns without calorie control — work for some, but adherence is low.

Nutrition: the 80% factor

Nutrition is by far the most important factor (estimated 70-80% of the result). It comes down to two principles: a calorie deficit of 300-500 kcal per day, and the quality of what you eat within that deficit.

For belly fat specifically, protein-rich eating works best. Aim for 1.6 to 2.2 grams of protein per kilogram of body weight. This gives maximum satiety, preserves muscle mass during weight loss, and has a thermogenic effect (protein costs 20-30% more energy to process than carbohydrates).

Do not cut out any food group completely, but focus on minimally processed food: meat, fish, eggs, legumes, wholegrain products, vegetables, fruit, nuts. Drastically reduce: ultra-processed snacks, soft drinks/juice, alcohol (a strong driver of belly fat), sugary desserts.

A Mediterranean eating pattern is superior in studies for visceral fat reduction — fish twice a week, olive oil, vegetables, legumes, little red/processed meat.

Exercise: strength and HIIT

Exercise is the other 20-30% of the result. For belly fat specifically, a combination works best.

• Strength training 2-3x per week — building muscle mass raises resting metabolism and protects against visceral fat. Compound exercises (squat, deadlift, rowing) are more effective than isolation exercises.
• HIIT 1-2x per week — short intervals (20-30s all-out, 1-2 min rest) demonstrably burn more visceral fat than steady-state cardio for the same time investment.
• Daily movement — aim for 8,000-10,000 steps. Prolonged sitting increases visceral fat even with sufficient exercise.
• Specific abdominal exercises (planks, dead bug, ab wheel) — not for fat loss but for core stability and visibility of results.
• Strength training is extra important for women after menopause: it tempers the effects of oestrogen loss on fat and bone.

Sleep, stress and hormones

Sleeping less than 7 hours per night increases visceral fat independently of food intake. Poor sleep disrupts ghrelin (hunger), leptin (satiety) and cortisol (fat storage around the abdomen).

Chronic stress is an underestimated driver of belly fat. High cortisol levels stimulate fat storage specifically around the abdomen. For women after menopause this plays an even stronger role.

Practical interventions: 7-9 hours of sleep, fixed bedtimes, no screens for 1 hour before bed, 10-20 minutes of relaxation or meditation daily, limiting alcohol (disrupts sleep and stimulates belly fat).

A hormonal evaluation (TSH, oestradiol, testosterone, cortisol) is sensible with unexplained belly fat despite a healthy lifestyle. An underactive thyroid, low testosterone in men or declining oestrogen in women often explains stubborn belly fat.

When GLP-1 medication helps

GLP-1 receptor agonists (Ozempic, Wegovy, Mounjaro) are currently the most effective available means of reducing visceral fat. MRI studies show a 20-30% decrease over 12 months.

The mechanism of action fits belly fat well: delayed gastric emptying, appetite suppression, better insulin sensitivity and direct effects on fat tissue. People with type 2 diabetes or prediabetes in particular benefit extra because their visceral fat is usually elevated.

When to consider it? BMI ≥30, or BMI 27-30 with comorbidity (diabetes, hypertension, dyslipidaemia, sleep apnoea), or getting stuck after 6 months of serious lifestyle intervention. At Go Leaner a BIG-registered doctor always carries out an individual assessment.

Important: GLP-1 medication works best in combination with sufficient protein and strength training. Without these supporting interventions you lose up to 25-40% of the weight lost from muscle mass.

Realistic timeline

Weeks 1-4: 2-4 kg weight loss (much of it water/glycogen), waist circumference -1 to -3 cm. Motivation high.

Months 2-3: 3-5 kg weight loss, waist circumference -3 to -5 cm. Plateaus can occur — normal and temporary.

Months 4-6: 6-10 kg total. Visceral fat is largely gone for those who started with an increased waist circumference. Metabolic improvements (cholesterol, blood pressure, glucose) clearly measurable.

Months 6-12: 10-15 kg total, waist circumference -8 to -12 cm. Maintenance phase begins. Important: keep up strength training and protein, otherwise fat (and usually belly fat in particular) returns quickly.

Practical 12-week plan

Weeks 1-2: measure waist circumference, weight and waist-to-hip ratio. Photos from 3 angles. Cut out soft drinks/juice completely. Start with 8,000 steps per day.

Weeks 3-4: introduce strength training 2x per week (full body). Increase protein to 1.6 g/kg. Count calories for one week to create awareness.

Weeks 5-8: add HIIT 1x per week. Optimise sleep (fixed bedtime). Evaluate waist circumference every 2 weeks.

Weeks 9-12: if there is little result despite adherence: blood tests (TSH, glucose, insulin, lipid panel) and consider a medical consultation. Much stubborn belly fat has an underlying metabolic component that improves considerably with GLP-1 medication.

Goal after 12 weeks: 5-8 kg weight loss, 5-8 cm reduction in waist circumference, restoration of a healthy waist-to-height ratio (<0.5).