Untreated Obesity: What Diseases Develop and Why It's Dangerous

If excess weight is just 'a few extra kilograms,' why are doctors worldwide sounding the alarm?

The numbers speak for themselves. In 2024, over half a billion people live with diabetes, and the forecasts are grim: by 2050, this number will double to 1.3 billion [33]. Obesity accounts for 44% of all type 2 diabetes cases [33]. According to World Obesity Federation projections, by 2035, more than 51% of the world's population will be overweight [33].

But there's good news too. Most obesity complications are reversible. A 10-15% weight reduction can dramatically change your health picture. And that's exactly what we'll discuss.

Why is obesity a medical condition, not cosmetics?

Obesity is a chronic progressive condition characterized by excessive accumulation of adipose tissue in the body. According to WHO definition, obesity is diagnosed at body mass index (BMI) ≥30 kg/m² [46].

And it's not just about the numbers on the scale. Adipose tissue is an active endocrine organ. It produces hormones, cytokines, and inflammatory mediators that affect the entire body.

When adipose tissue accumulates in the visceral zone (around internal organs), it triggers a cascade of metabolic disorders. Pro-inflammatory cytokine levels increase, insulin sensitivity is impaired, blood pressure rises.

Therefore, obesity isn't an aesthetic issue. It's a matter of heart, liver, joint, hormonal system health, and even cancer risk.

Want to find out your BMI? Use the BMI calculator on our website.

How does obesity cause type 2 diabetes and metabolic syndrome?

Type 2 diabetes is the first complication that comes to mind. And for good reason. The connection between excess weight and glucose metabolism disorders is so strong that obesity is considered the main risk factor.

The statistics are striking. According to global research:

• Over 500 million people live with diabetes in 2024
• 2050 forecast: 1.3 billion diabetic patients
• 44% of all type 2 diabetes cases are linked to obesity [33]

Metabolic syndrome is a complex of disorders that often accompanies obesity. It includes:

• Abdominal obesity (waist circumference >102 cm in men, >88 cm in women)
• Elevated blood pressure
• Impaired glucose tolerance
• Dyslipidemia (elevated triglycerides, reduced 'good' cholesterol)

Research shows a deep connection between obstructive sleep apnea, obesity, and metabolic syndrome. Both conditions significantly increase cardiovascular disease risk [27].

Read more about obesity: types, causes and correction approaches in our guide.

What happens to the heart and blood vessels with obesity?

Cardiovascular diseases are the leading cause of death worldwide. And obesity is one of the key risk factors.

Excess weight affects the cardiovascular system through several mechanisms:

According to the European Society of Cardiology (ESC) consensus, obesity is closely associated with atherosclerotic cardiovascular disease development. This connection is partially mediated through classic risk factors: diabetes, hypertension, dyslipidemia. But visceral adipose tissue also directly contributes to atherosclerosis development by increasing inflammatory marker levels [20].

But there's also positive news. Clinically significant blood pressure reduction is achieved even with moderate weight loss. Research confirms the effectiveness of weight reduction through lifestyle changes and, when necessary, medication support [20].

Sleep apnea, liver, and joints: how weight burdens organs?

Obstructive Sleep Apnea (OSA)

Obstructive sleep apnea is extremely common among people with obesity. The mechanism is simple: excess fat deposits around the upper airways, narrowing them. During sleep, muscles relax, and airways periodically become blocked.

According to global data, using the criterion of 5 or more episodes per hour, OSA affects nearly 1 billion people. 425 million adults aged 30-69 have moderate or severe apnea (15+ episodes per hour) [25].

Sleep apnea consequences extend far beyond poor sleep:

• Increased risk of cardiovascular events
• Increased mortality
• Daytime sleepiness and reduced quality of life
• Cognitive impairment

A study in Chest journal showed that in patients with obesity and sleep apnea, tirzepatide treatment reduced overall mortality risk (HR 0.443), major cardiovascular events (HR 0.731), and renal complications (HR 0.427) [7].

Non-Alcoholic Fatty Liver Disease (NAFLD)

NAFLD is fat accumulation in the liver unrelated to alcohol consumption. It's the most common chronic liver disease worldwide.

In the US, NAFLD (now MASLD - metabolic dysfunction-associated steatotic liver disease) affects 80-100 million people. Forecast: by 2030, the number of patients will grow to 100.9 million [24].

Liver fibrosis stage is independently associated with overall and liver-specific mortality, regardless of other histological features [2]. Therefore, early detection and weight correction are critically important.

Osteoarthritis (OA)

Joints suffer directly from excess weight. Every extra kilogram of body weight creates additional load of 3-6 kg on knee joints when walking.

According to WHO data, in 2019, about 528 million people worldwide lived with osteoarthritis - a 113% increase from 1990. The knee is the most commonly affected joint (365 million cases) [36].

Lancet Rheumatology research predicts: by 2050, nearly 1 billion people will live with osteoarthritis. Population aging, rising obesity, and injuries are key drivers [34].

It's important to understand: obesity affects joints not only mechanically. Adipose tissue produces pro-inflammatory mediators (adipokines) that directly damage cartilage tissue [35].

For every kilogram of excess weight, osteoarthritis development risk increases by approximately 10% [41].

Which cancer types are linked to obesity and how much does risk increase?

Obesity increases the risk of at least 13 cancer types. This isn't a hypothesis - it's a proven fact confirmed by large-scale studies.

A meta-analysis of 230 cohort studies confirmed: overweight and obesity are associated with increased risk of many cancer types [5].

Interestingly, even in women with normal BMI but elevated body fat percentage (so-called 'hidden obesity'), postmenopausal breast cancer risk increases [4].

Mental Health

Obesity affects not only the body. People with excess weight more often suffer from:

• Depression
• Anxiety disorders
• Reduced self-esteem
• Social isolation

Joint pain, limited mobility, medication side effects, and other obesity-associated factors can lead to complications not directly caused by the disease [47].

Good news: most complications are reversible

Despite the seriousness of consequences, there's an extremely important fact: most obesity complications improve or completely disappear with weight loss.

What happens with weight loss?

Diabetes and metabolism:

• Insulin sensitivity improves
• Fasting glucose levels decrease
• Risk of prediabetes progressing to diabetes reduces

Cardiovascular system:

• Clinically significant blood pressure reduction
• Lipid profile improvement
• Inflammatory marker reduction

Sleep apnea:

• Weight loss interventions consistently reduce OSA severity
• CPAP therapy need decreases
• Cardiometabolic parameters improve [6]

Liver:

• Fatty infiltration reduction
• NASH inflammation regression
• Fibrosis progression slowing

Joints:

• The IDEA Trial showed: significant weight loss substantially reduces inflammation markers and improves knee joint condition [32]
• Small studies confirm: even moderate weight loss improves joint health [32]

Cancer risks:

• In a large prospective study, women who intentionally lost more than 5% weight had lower cancer risk, especially endometrial cancer [13]
• In the Women's Health Initiative study, women who lost ≥5% weight had lower invasive breast cancer risk [13]

How DOZA helps achieve results

At DOZA, we understand: weight loss isn't about willpower. It's about the right tools and support.

Modern tirzepatide-based medications (for example, Mounjaro) show impressive results. In the SURMOUNT-1 study, participants lost up to 22.5% of their weight over 72 weeks.

The DOZA program includes:

• Individual product and dosage selection
• Continuous specialist support
• Gradual program exit for result maintenance
• Support in forming healthy eating habits

Learn more about the DOZA weight loss program or how Mounjaro works.

Frequently asked questions about obesity complications

Summary

Obesity isn't a cosmetic problem or a matter of laziness or weak will. It's a chronic medical condition that affects the entire body: from heart to joints, from liver to mental health.

But most importantly - complications are reversible. A 10-15% weight reduction can dramatically improve health. Modern weight correction methods under specialist supervision make this path real and achievable.

If you're ready to take the first step — write to us on Telegram @Doza_sofia_bot↗. The consultation is free and doesn't commit you to anything.