Key points
- 'Obese' is a medical term used to describe a person with a high excess of body fat.
- A person is described as obese if their body mass index (BMI) is greater than 30 kg/m².
- BMI is just one way to measure obesity.
- An obese person is at greater risk of A disease more common in older people where person's body cells no longer respond to insulin produced by the pancreas., heart disease and some types of cancer.
Obesity and exercise
Video
A school fitness adviser explains what obesity is and the steps that can be taken to avoid it. Where diabetes is referred to in this video, it specifically relates to Type-2 diabetes.
The role of diet in reducing obesity is vitally important to make sure that we don't consume more calories than we actually burn off.
Obesity is where someone is overweight and has excess of body fat. Balanced diet is equally important as daily exercise. They both play a fundamental part in maintaining a healthy weight.
Exercise is so important because it's great for everybody's physical and mental wellbeing. We need to be walking, we need to be trying to get our heart rate up which is the most important part about being active. The heart is a muscle, and we need to work that on a daily basis.
Some daily examples are walking to school, really fun but walking at a brisk pace. Taking the stairs instead of the lift. Drop a stop earlier from the bus stop and walk home.
Well, how you can tell if someone is obese is you perform a BMI test which is a body mass index test. BMI is calculated using a person's height and weight. If you're above 25, you are overweight. If you are between 30 and 40, you're considered obese. And anybody above 40 is very obese.
Someone at an obese stage in their life is more at risk of heart attack, strokes, and diabetes and associated illnesses.
The science I learned at school was really important to understand how the body works and what's needed to lead a healthy lifestyle.
My top three tips would be daily activities which are fun that you're gonna be want to doing again, a balanced healthy diet, and my third tip is to make sure you commit to this as a family.
Can you answer these questions based on the video?
1. Body mass index - BMI - is calculated using a person's height and …?
2. According to the video, which two words describe how a diet should be?
A person's height and weight.
Balanced and healthy.
What is obesity?
A person is said to be obese if they have such a high excess of body fat that their health might be affected.
Health workers use body mass index (BMI) to assess obesity. They measure the height and mass of a person and then use the equation below to calculate their BMI:
BMI = mass (kg) ÷ height² (m²)
For example, if a person has a mass of 60 kg and a height of 1.65 m:
BMI = 60 kg ÷ 1.65²
BMI = 22 kg/m²
A person is overweight if their BMI is between 25 kg/m² and 30 kg/m². A person with a BMI over 30 kg/m² is said to be obese.
Therefore, the person in this example can be described as being a healthy weight.
How might someone become obese?
Energy balance is the relationship between energy input (calories consumed through food and drink) and energy output (calories used by the body for our energy requirements).
This relationship dictates whether weight is lost, gained, or remains the same.
A person might become obese by eating food that supplies more energy than they need.
A 13-year-old girl needs about 9,000 kilojoules (KJ) of energy each day. Boys the same age needs around 10,000 KJ/day. Adult women need roughly 8,400 KJ/day and adult men need roughly 10,500 KJ/day.
If people consistently eat food that supplies more energy than this, without taking extra exercise, they might eventually become obese.
Health problems related to obesity
Obesity increases the risk of life-threatening health problems, including:
- Heart disease
- Stroke
- Type 2 diabetes
- Some types of cancer, including cancers of the breast, bowel and liver
A person can prevent obesity by eating sensible amounts of nutritious food and exercising regularly.
Test your knowledge
Quiz - Health and obesity
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