Obese vs overweight: Exploring the differences

The terms 'overweight' and 'obese' are often used interchangeably but they have separate meanings. Put simply, being overweight means having more body weight than what's considered the healthy weight range, while obesity is a chronic condition that represents a severe form of excess fat and weight.

Plus, to be classified as either overweight or obese, you have to meet different body mass index (BMI) scores. It's also important to note that oftentimes being overweight can lead to obesity in the long-term, which puts people with obesity at an increased risk of developing weight-related health problems too.

That's why we're uncovering the key differences, what body mass index classifies someone as overweight or obese at a population level, and how to lose weight holistically and healthily.

What is considered overweight?

The Australian Institute of Health and Welfare (AIHW) reports that 2 in 3 adults and 1 in 4 children and adolescents are considered obese or overweight, with 17% being considered the latter [1]. Furthermore, by 2025, experts say that 3 in 4 Australian adults will either be overweight or obese.

So how do you figure out what classifies someone as overweight?

In Australia, we use the body mass index (BMI) as a screening tool to classify overweight people. Your BMI is a calculation of body fat, which divides kilograms — your weight — by metres squared — your height.

A BMI between 25 and 29.9 is generally considered overweight, but it's important to note that for some people, a BMI measure isn't always as accurate [2].

Certain groups of people naturally have different muscle and fat mass, like athletes who often have a high muscle mass. If we only measured these groups of people based on their BMI, they would be considered overweight or obese even though their body fat is low and they are at a healthy weight [2].

That's why waist circumference can also be used to assess your weight. The AIHW, as well as The World Health Organisation (WHO), classify overweight and obesity as having an increased chance of metabolic risk and a waist circumference above 94 cm for men and 80 cm for women (who aren't pregnant) [3] [4].

What is considered obese in Australia?

The BMI and waist circumference measurements are also used to determine obesity. According to WHO, a BMI greater than 30 or a waist circumference of 102cm in men and 88cm in women is classified as obesity [2][5].

Healthcare professionals and doctors may also measure blood pressure, blood sugar (glucose), and cholesterol (lipid) levels to determine whether you're at an increased risk of other medical conditions related to obesity [2].

Overweight vs obesity: what are the differences?

Both overweight and obesity are defined as the accumulation of abnormal and excess fat that can lead to health problems. While they're related, there are some significant differences between them.

Being overweight means having more body weight than what is considered a normal or healthy weight range in line with one's age group and build. On the other hand, obesity is a more severe form of excess weight and body fat.

Obese people carry increased risk factors for medical conditions like the ones we mentioned above, and obesity is considered one of the chronic conditions that require treatment and management in the long term [2].

Longitudinal studies examining the relationship between overweight and obesity found that overweight people have a major risk factor for becoming obese in the future in comparison to those who start with a normal or healthy weight [6].

A study published in the American Journal of Clinical Nutrition found that overweight children and adolescents have a 70% chance of becoming obese adults [6]. Plus, it's estimated that roughly 55% of obese children will become obese in adolescence, and roughly 80% of obese adolescents will still be obese in adulthood [7].

What causes overweight and obesity?

There are a bunch of complex factors that can lead to weight gain, an often gradual process where the body accumulates more energy from food intake and calories than it needs.

The average adult only needs 8700 kJ (around 2079 calories) per day and any extra energy consumed is stored as body fat. Some of the most common causes and factors influencing a person's weight are [2]:

• Family history: The genes you've inherited from your parents and the habits around diet and physical activity that you were taught.
• Your environment: The types of foods that are available to you and lifestyle factors like living a sedentary lifestyle.
• Your metabolism: How your body turns food into energy and the rate at which your body burns energy.
• Different medical conditions: These can cause weight gain or make it more difficult to lose weight.
• Certain medications: Weight gain is a side effect of different kinds of medications.

How to calculate your BMI

Body mass index is used to estimate the total amount of fat in relation to your weight and height. As we explained before, you can calculate it by taking your weight in kilograms and dividing it by your height in metres squared.

There are also handy online tools, like NSW Government's BMI Calculator, that help you understand whether you're at a healthy weight, or have excess body weight and should consider starting a weight loss journey.

What are the health risks of being overweight or obese?

Being overweight and obese doesn't just mean you carry extra body fat. Excess weight, and obesity in particular, puts people at a substantially increased risk of major medical conditions and other chronic conditions.

Being overweight and obese has actually become the second leading cause of Australia's disease burden, accounting for 8.4% of the total burden and 19.3% of the cardiovascular burden [8].

As excess weight rises, especially when people are classified as having severe obesity or being morbidly obese, the risk factor for developing these conditions also rises. Plus, people who are overweight or obese also have higher rates of death [8].

How to approach weight loss

When it comes to weight loss, we believe in taking a sustainable approach that considers your body's unique metabolism on a biological level and recognises the need to make lifestyle changes like improving your diet and moving your body regularly.

This involves taking small, incremental steps to change your lifestyle so that it works for your needs and fits into your routine. That's why Juniper’s Weight Reset Program takes a holistic approach to weight loss, helping you achieve long-term and sustainable results.

Get treatment that targets weight gain on a biological level, plus a dietitian-led program that supports long-term weight maintenance.

We help you make habit changes to increase your physical activity levels and promote a balanced and nutritious diet, by arming you with 1-on-1 health tracking and weekly check-ins with your health practitioner. We track your biometric, mental, and physical health, continuously adjusting your program to suit your individual needs, and helping you get to a healthy weight range and become your most confident self.