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
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.
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)
Go deeper: metabolic-health webinars
Recorded webinars on insulin resistance, blood sugar and the root causes of weight loss – with Dr Saadi.
BMI, 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 |
| Kehatasand rasva % (M) | 10–20 % | 20–25 % | > 25 % |
| Kehatasand rasva % (N) | 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
Kehatasand rasva % (M)
- Optimaalne
- 10–20 %
- Ülekaal
- 20–25 %
- Kõrge risk
- > 25 %
Kehatasand rasva % (N)
- Optimaalne
- 18–28 %
- Ülekaal
- 28–33 %
- Kõrge risk
- > 33 %
Vistseraalne rasv (skoor)
- Optimaalne
- 1–9
- Ülekaal
- 10–14
- Kõrge risk
- ≥ 15
BMI on ligikaudne – lihaselisel inimesel võib olla „ülekaal“ ilma rasvahaiguseta. Vööümbermõõt ja kehakoostise analüüs on täpsemad.
Frequently asked questions
Related topics
Metabolic health is interconnected – explore the other deep-dives:
Insulin resistance
The root of metabolic disease – 5–10 years before diabetes appears.
ReadVagus nerve
The rest-and-repair system – digestion, heart, inflammation, stress.
ReadCholesterol & ApoB
Expanded lipid panel – ApoB, Lp(a), homocysteine, A vs B phenotype.
ReadSleep
The foundation of metabolic health – hormones, cortisol, insulin, brain recovery.
ReadChronic inflammation
The ‘silent fire’ behind cardiovascular disease, diabetes and autoimmunity.
ReadLow-carb and keto
Carbohydrate restriction – IR, T2D, fatty liver, metabolic syndrome.
ReadTeaduslikud allikad
- Fothergill E et al. Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity, 2016. doi.org/10.1002/oby.21538
- Hall KD, Kahan S. Maintenance of Lost Weight and Long-Term Management of Obesity. Medical Clinics of North America, 2018. doi.org/10.1016/j.mcna.2017.08.012
- Frayling TM et al. A common variant in the FTO gene is associated with body mass index and predisposes to obesity. Science, 2007. doi.org/10.1126/science.1141634
- Wilding JPH et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity (STEP 1). NEJM, 2021. doi.org/10.1056/NEJMoa2032183
- Leidy HJ et al. The role of protein in weight loss and maintenance. American Journal of Clinical Nutrition, 2015. doi.org/10.3945/ajcn.114.084038
- Jakubowicz D et al. High caloric intake at breakfast vs. dinner differentially influences weight loss. Obesity, 2013. doi.org/10.1002/oby.20460
- Westerterp-Plantenga MS. Sleep, circadian rhythm and body weight. Proceedings of the Nutrition Society, 2016. doi.org/10.1017/S0029665116000227
- Villareal DT et al. Aerobic or Resistance Exercise, or Both, in Dieting Obese Older Adults. NEJM, 2017. doi.org/10.1056/NEJMoa1616338
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
Want to know why the weight won’t move?
In the consultation we review your labs, body composition, HOMA-IR and hormonal context and build an individual plan you can discuss with your GP and/or other treating clinicians.
Booking information and contactThis 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.