Does a BMI over 30 always mean obesity?

On average, yes – but not always for every individual. Athletes can have a high BMI just from muscle, not fat. Body composition and waist size tell you more about your health than BMI alone.

Why can’t I lose weight even though I barely eat?

Common reasons: (1) you’re actually eating more than you think, from snacks, drinks and sauces, (2) insulin and leptin resistance are blocking fat burning, (3) poor sleep and stress, (4) a mildly underactive thyroid that hasn’t been diagnosed yet, (5) too much cardio and not enough strength training has slowed your metabolism. Lab tests and an accurate food log usually help find the answer.

Are GLP-1 drugs (Ozempic, Wegovy) the answer?

These drugs are effective for specific medical reasons and are prescribed by your doctor. They don’t change your habits on their own – weight often comes back after stopping, and losing muscle during treatment is common. This decision should be made with your doctor, alongside high protein intake and strength training to protect your muscle.

How fast is it safe to lose weight?

0.5–1% of your body weight per week is a sustainable pace. Faster than that usually means you’re losing muscle and water, not fat. Patience is the most important factor in losing fat.

Short fasting windows (12–16 hours) are safe for most healthy adults. Longer fasts (24 hours or more) should only be done under a doctor’s supervision, especially if you take medications, are pregnant or breastfeeding, or have a history of an eating disorder.

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Weight & metabolism

Overweight and obesity

Excess weight is not about willpower. It is a hormonal and metabolic issue. Often the root cause is not “eating too much, moving too little,” but chronically high insulin (the hormone that controls blood sugar), leptin resistance (when the brain stops getting the “I’m full” signal), and a broken satiety signal.

70%+ of Estonian adults are overweight or obese
“Calories in – calories out” ignores hormonal context
Reversible with the right protocol and patience

See webinars Insulin resistance checklist

Metsatee jalutuskäigul – kaalulangetamise elustiili tugi

What does “overweight” actually mean for your metabolism?

Doctors classify weight using BMI (body mass index – your weight divided by your height squared): 25–29.9 is overweight, 30 or above is obesity. But BMI is a rough tool – it can’t tell muscle from fat, or show where the fat sits on your body. Waist size and visceral fat (fat around your internal organs) matter more for your health.

Body fat is not just storage – it works like an active hormone-producing organ. It releases leptin (the fullness signal), adiponectin (which helps cells respond to insulin), and substances that cause inflammation. When there is too much fat – especially around the organs – it throws off your hormone balance and makes it easier to keep gaining weight.

In most cases, being overweight is a result of insulin resistance and leptin resistance, not the cause. Insulin resistance means your cells stop responding well to insulin (the hormone that manages blood sugar). Leptin resistance means your brain stops receiving the “I’m full” signal. High insulin blocks fat burning, and the fullness signal never reaches the brain. That’s why you feel hungry, tired, and keep gaining weight – no matter how much willpower you have.

Signs it’s not just about eating too much

Waist size of 94 cm or more in men, 80 cm or more in women
Weight won’t drop even when eating fewer calories
Sugar cravings in the evening, hard to stop eating at dinner
Hunger returns within 2–3 hours of eating
Feeling tired and drowsy after lunch
Eating at night or waking up hungry
Puffiness (face in the morning, tight rings or shoes in the evening)
Weight comes right back after every diet

Why strict dieting fails in the long run

Cutting calories too sharply slows down your thyroid (which makes the hormone T3), lowers leptin, and causes muscle loss. Your body goes into “energy-saving mode” – your resting metabolism (how many calories you burn at rest) can drop by 20–25% (Rosenbaum, Am J Clin Nutr 2008). Once the diet ends, you go back to eating normally but now burn fewer calories – so the weight comes back, often with extra.

A 6-year follow-up of contestants from the show Biggest Loser found their resting metabolism stayed slowed down even after they regained the weight (Fothergill, Obesity 2016). This isn’t a willpower problem – it’s the body adapting.

Main root causes

Insulin resistance (cells stop responding well to insulin) and chronically high insulin – blocks the body from burning fat
Leptin resistance – the brain doesn’t get the fullness signal
Sugary drinks and refined carbs – cause insulin spikes and hunger again just 2 hours later
Snacking and eating over a long window (more than 14 hours a day) – insulin never drops low enough for fat-burning to happen
Poor sleep – even one bad night raises the hunger hormone ghrelin and lowers leptin (Spiegel, Ann Intern Med 2004)
Chronic stress and high cortisol (the stress hormone) – keep fat stored on the belly and increase sugar cravings
An underactive thyroid (Hashimoto’s disease, or mild, not-yet-diagnosed hypothyroidism)
Endocrine disruptors (chemicals like BPA and phthalates that interfere with hormones) – these change how fat cells develop
Low muscle mass – this slows metabolism and reduces the body’s ability to handle sugar
Certain medications – corticosteroids, some antidepressants and antipsychotics, insulin
Perimenopause and menopause – falling oestrogen levels increase fat around the belly

Holistic approach

Weight loss without restoring metabolic health is temporary. Four pillars for durable change:

Nutrition

Eat enough protein (1.4–1.8 g per kg of body weight) – it helps protect muscle and keeps you feeling full longer. Cut back on refined carbs and sugary drinks. Eat 2–3 meals a day with no snacking, inside an 8–10 hour window. Add vegetables to every meal.

Strength training first

Without strength training, 25–30% of weight lost is muscle, not fat. Losing muscle slows your metabolism and makes it more likely the weight comes back. Strength training 2–3 times a week protects muscle, improves how your cells respond to insulin, and burns fat even while resting. Cardio is a bonus, not the foundation.

Supplements that may help with fat and weight

No supplement replaces good nutrition, strength training and sleep. But a few can support fat metabolism and help you feel full. If you take medications or have a chronic condition, check with your doctor before starting any of these.

Protein powder (whey or pea) – an easy way to get more protein, helps with fullness and keeping muscle
Berberine – improves how your cells respond to insulin and supports fat burning; can interact with some medications
Omega-3 (EPA/DHA, healthy fats) – lowers inflammation linked to metabolism, supports muscle
Magnesium glycinate – supports sleep and blood sugar control
Vitamin D – low levels are linked to higher body fat; get your level tested first
Creatine monohydrate (3–5 g/day) – improves exercise performance, helps preserve muscle
Fiber (psyllium, acacia) – keeps you feeling full longer, supports gut health
L-carnitine – helps the body use fat as fuel during longer cardio workouts

Time-restricted eating and fasting

Shortening your eating window to 8–10 hours a day lowers your average insulin level, gives your body more time to burn fat, and makes it easier to control calories without constant willpower. For most people this works better long-term than classic calorie counting.

A study by Moro and colleagues (2016, J Transl Med) found that trained men following a 16:8 pattern (16 hours without food, 8 hours to eat) lost fat while keeping their muscle and strength – with the same protein and calorie intake as a normal eating pattern.

Start with a 12-hour gap between dinner and breakfast, then extend it gradually. Don’t train on an empty stomach when you’re just starting out. This approach isn’t suitable during pregnancy, breastfeeding, if you have a history of an eating disorder, or while taking certain medications.

See the study (J Transl Med)

Tests that show the real picture

Body composition test (bioimpedance or a DEXA scan) – shows muscle, fat and water in your body
Waist circumference (under 94 cm for men, under 80 cm for women is a good target)
Fasting insulin and HOMA-IR (a score that shows how well your cells respond to insulin)
Fasting glucose and HbA1c (your average blood sugar over the past 2–3 months)
Triglyceride to HDL ratio (above 1.5 is a warning sign)
Thyroid panel: TSH, free T4, free T3, TPO antibodies
Vitamin D (25-OH) and ferritin (iron stores)
hs-CRP – a marker of low-grade, hidden inflammation in the body
Cortisol (the stress hormone) – morning saliva test or a 4-point curve through the day
Sex hormones: testosterone, oestradiol, and SHBG (a protein that carries sex hormones in the blood)

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KMI, vööümbermõõt ja kehakoostise normid

Riskihindamine täiskasvanule

Marker	Optimaalne	Ülekaal	Kõrge risk
BMI (kg/m²)	18,5–24,9	25,0–29,9	≥ 30,0
Vööümbermõõt (M)	< 94 cm	94–102 cm	> 102 cm
Vööümbermõõt (N)	< 80 cm	80–88 cm	> 88 cm
Vöö / puusa suhe (M / N)	< 0,90 / 0,85	0,90–1,0 / 0,85–0,90	> 1,0 / > 0,90
Kehakoostis: rasva % (mehed)	10–20 %	20–25 %	> 25 %
Kehakoostis: rasva % (naised)	18–28 %	28–33 %	> 33 %
Vistseraalne rasv (skoor)	1–9	10–14	≥ 15

BMI (kg/m²)

Optimaalne: 18,5–24,9
Ülekaal: 25,0–29,9
Kõrge risk: ≥ 30,0

Vööümbermõõt (M)

Optimaalne: < 94 cm
Ülekaal: 94–102 cm
Kõrge risk: > 102 cm

Vööümbermõõt (N)

Optimaalne: < 80 cm
Ülekaal: 80–88 cm
Kõrge risk: > 88 cm

Vöö / puusa suhe (M / N)

Optimaalne: < 0,90 / 0,85
Ülekaal: 0,90–1,0 / 0,85–0,90
Kõrge risk: > 1,0 / > 0,90

Kehakoostis: rasva % (mehed)

Optimaalne: 10–20 %
Ülekaal: 20–25 %
Kõrge risk: > 25 %

Kehakoostis: rasva % (naised)

Optimaalne: 18–28 %
Ülekaal: 28–33 %
Kõrge risk: > 33 %

Vistseraalne rasv (skoor)

Optimaalne: 1–9
Ülekaal: 10–14
Kõrge risk: ≥ 15

KMI on ligikaudne – lihaselisel inimesel võib see näidata ülekaalu ka siis, kui rasva on vähe. Vööümbermõõt ja kehakoostise analüüs on täpsemad.

Frequently asked questions

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Dr Sergey Saadi – expert in metabolic health and the root causes of weight gain

Dr Sergey Saadi is a physician with over 15 years of clinical practice.

Thousands of consultations for metabolic-health and weight concerns
Author of “Dangerous secrets of blood sugar” (Varrak)
Clinical approach: body composition + hormonal panel + lifestyle audit
No one-size-fits-all diets – individual root-cause analysis

This page is educational and general. It is not personal medical advice, a diagnosis or a treatment plan. Discuss changes to your health, medications or supplements with your doctor.

Overweight and obesity

What does “overweight” actually mean for your metabolism?

Signs it’s not just about eating too much

Why strict dieting fails in the long run

Main root causes

Holistic approach

Supplements that may help with fat and weight

Time-restricted eating and fasting

Tests that show the real picture

Read the full article

Go deeper: metabolic-health webinars

KMI, vööümbermõõt ja kehakoostise normid

Frequently asked questions

Go deeper: related materials

Related topics

Teaduslikud allikad

Dr Sergey Saadi – expert in metabolic health and the root causes of weight gain

Dr Sergey Saadi sees patients at Synage Clinic

Overweight and obesity

What does “overweight” actually mean for your metabolism?

Signs it’s not just about eating too much

Read the full article

Go deeper: metabolic-health webinars

KMI, vööümbermõõt ja kehakoostise normid

Frequently asked questions

Does a BMI over 30 always mean obesity?

Why can’t I lose weight even though I barely eat?

Are GLP-1 drugs (Ozempic, Wegovy) the answer?

How fast is it safe to lose weight?

Is fasting safe?

Miks kalorite lugemine ei tööta pikaajaliselt?

Kas geneetika määrab ülekaalu?

Miks tekib „platoo“ kaalulangetamise ajal?

Kas hormonaalne ülekaal on olemas?

Kui palju valku peaks sööma kaalulangetuse ajal?

Kas GLP-1 ravimid (Ozempic, Wegovy) on lahendus?

Kas vahelduv paastumine töötab kaalulangetamiseks?

Kas magneesium ja teised mikrotoitained mõjutavad kaalu?

Mis kell päevas peaks sööma?

Kas jõutreening on olulisem kui kardio kaalulangetamiseks?

Go deeper: related materials

Related topics

Teaduslikud allikad

Dr Sergey Saadi – expert in metabolic health and the root causes of weight gain

Dr Sergey Saadi sees patients at Synage Clinic