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Obesity Class I

Your result:

BMI Classification Table
BMI Classification
Under 18.5 Underweight
18.5 - 24.9 Normal Weight
25-29.9 Overweight
30-34.9 Obesity Class I
35-39.9 Obesity Class II
Over 40 Obesity Class III

*This BMI calculator is for adults 20 years or older. Talk to your doctor about your BMI if you're under the age of 20.

What does this mean for you?

Having a BMI of 30-34.9 places you in the category Obesity Class 1. This means that you are at risk of developing obesity-related diseases. Losing weight will reduce the risk of developing obesity-related diseases significantly. Read about the health benefits.

There are scientifically-proven treatment options for obesity that can help you manage your weight depending on your unique needs and situation. Check them out to start making a change.

Find your local weight management provider

Talk to your weight management provider about treatment options that could prevent the weight you lose from coming back.


A healthcare provider can make recommendations depending on the specific needs, current health status, and whether there are any weight-related complications.

Treatments include:

  • Healthy Eating
  • Increased physical activity
  • Behavioural therapy
  • Meal replacements / low energy diets
  • Weight loss medications
  • Bariatric surgery*

Tips and advice for you

A healthy lifestyle is recommended for everybody. However if your BMI shows that you're overweight or have obesity at any point, it may be time to make changes so that you can be at a healthier weight. Many things can affect your weight, so you can also try to manage it in different ways. Click on an item below to see what you can do to make a change.


There's no perfect diet for losing weight. But, there are scientifically proven ways to help you manage weight and prevent the weight from coming back. Focus on healthier ways of eating (like the Mediterranean diet, high fiber diet, and vegetarian diet) instead of going to extremes in limiting how much you eat.

Mental health

There are many reasons why we gain weight and sometimes, they have to do with how we feel. Some people use food to cope with difficult situations and soothe their feelings. This is called emotional eating - and it's the reason why we sometimes need psychological support instead of diet advice. Get a better understanding of the roles feelings and stress play in managing weight.


Regular exercise is very important for losing and managing your weight. To make sure that your obesity weight loss programme is as effective as possible, consider adding aerobic and resistance exercises to your routine. You should also move more in general.

Find tips for getting a good start on a new exercise programme here.


Getting too little sleep can affect your hormones, which can then affect how and what you eat. When you sleep better, you're better able to make healthy choices and resist tempting foods. Find tips to improve your habits and get the sleep your body and mind need.

Your obesity health risk

Living with overweight or obesity is associated with an increased risk of mortality and other diseases or conditions. Generally, the higher your BMI, the greater the chance of developing other chronic obesity-related diseases. See the health benefits of losing weight.

Frequently asked questions

Why is BMI important to know?

BMI is a good way to check your risk of diseases related to body fat (adiposity). Generally, the higher your BMI, the greater the chance of developing other chronic obesity-related diseases, including:

  • Type II diabetes
  • Cardiovascular disease
  • Stroke
  • High blood pressure
  • Infertility
  • Depression and anxiety
  • Coronary heart disease
  • Dyslipidemia
  • Nonalcoholic fatty liver disease (NAFLD)/Nonalcoholic steatohepatitis (NASH)
  • Gastroesophageal reflux disease (GERD)
  • Metabolic syndrome (MetS)
  • Urinary incontinence
  • Obstructive sleep apnea and breathing problems
  • Chronic kidney disease
  • Various types of cancer: including but not limited to - breast, colon, endometrial, oesophageal, kidney, ovarian, and pancreatic cancer
  • Knee osteoarthritis
  • Gallstone disease
  • Thrombosis
  • Gout
  • Increased risk of mortality compared to those with a healthy BMI

Ask your healthcare professional for more information about any of these diseases and how they relate to your BMI.

What are the limits of BMI?

BMI is a simple and objective measurement, but it can be misleading in certain cases and for some groups of people. Research has shown that BMI is less accurate in predicting the risk of disease in people who are older, athletes, those who are tall or short, and those with more muscular body types. For example, elite athletes or bodybuilders have more muscle and weigh more, which makes their BMI higher.

BMI also doesn't take into account:

  • Hereditary risk factors associated with obesity-related diseases, such as metabolic syndrome
  • Environmental and lifestyle factors that can contribute to your risk of developing chronic disease
  • How body fat is distributed in individuals

It's important to remember that living with obesity doesn't necessarily mean you're unhealthy, just as being at a ‘normal’ weight doesn't mean you're healthy. Your BMI doesn't define you, but knowing and understanding your BMI can be a powerful tool for taking charge of your own health.

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