Have a question for our experts? This line is open until Friday, January 7th. Sangita will then answer the top questions and we’ll post the answers right here and on the forums.
Q: I just used an online BMI calculator and it said I was overweight! Should I be worried?
A: The BMI–or Body Mass Index– is one of many measurements that clinicians use to evaluate your overall risk for chronic diseases like diabetes, hypertension and heart disease. It is a calculation that takes into account the ratio of your weight to your height, which at the population level has been shown to correlate to disease risk.
- A BMI over 25 is considered to be ‘overweight’–meaning that there is shown to be an elevated risk of disease in groups of people at that BMI level.
- A BMI over 30 is considered to be obese, and suggests another cutoff point at which an even higher risk of disease is observed.
- Interestingly, health risk also increases at very low BMIs: a BMI less than 18.5 is considered underweight and is undesirable as well.
- BMIs between 18.5 and 24.9 are considered to be “normal,” meaning that there is no increased risk of health issues associated with people in that category.However, at the individual level, BMI alone is not predictive of whether a certain person is at increased risk for disease, because there are a lot of factors that influence the calculation itself–as well as factors that influence disease beyond weight–which make BMI an imperfect indicator of an individual’s health risk on its own. Read more at FYI Living.
Q: What causes obesity?
A: Consuming more food energy than can be used up in daily activity and normal body function (metabolism) generally results in excess energy being stored as body fat.
In terms of what you eat, ‘energy-dense’ foods (those that have a lot of kilojoules in a small volume) can be associated with weight gain, especially if you eat a lot of them. These foods tend to be high in sugar and/or fat, for example, soft drinks, chips and pastries. As for the other side of the equation — how much energy you expend — not being active (often simply not moving enough, let alone not formally exercising) is an important cause of obesity.
On top of these factors is a person’s genetic make up, that is, how easily they tend to store fat.