Do you find it difficult to get your weight down? If so, can keeping physically fit reduce the health risks? Or can keeping slim compensate if you don’t do much exercise?

Here’s what recent research suggests:

  • Being overweight (i.e. with a BMI of 25 – 30) doesn’t seem to shorten your life expectancy. Nor does having lower level obesity (with a BMI of 30 – 35). 
  • However, if you are more seriously obese, with a BMI over 35 this means you’re more likely to die younger. That’s the conclusion from a systematic review published in the Journal of the American Medical Association in 2013 – which looked at studies involving nearly 3 million people. 
  • Fortunately, there’s a way you can bring down your risk of developing or dying from heart disease or cancer if you are obese. Take regular exercise. Provided you are metabolically fit this can reduce your risk to that of someone who is a normal weight. That was the verdict from a study by US and European researchers published in the European Heart Journal in 2012. Unfortunately, research published in 2018, based on data from over half a million people in Europe, suggests the picture isn't quite so rosy. Following a healthy lifestyle reduces the risk of coronary heart disease (CHD), whetever your weight - but if you are overweight or obese you still increase the risk of CHD by over 25% compared to someone who is a normal weight.
  • Whether you are male or female obesity has other negative side effects – like pain. A survey of over a million Americans found that pain rates were 68% to 254% higher in people who were obese compared with those who weren’t. This was the case for both men and women. 

How can I tell if I’m overweight or obese?

A good starting point is to check your Body Mass Index. This measures whether you're a healthy weight for your height.

It isn’t a perfect measure. For example if you have a muscular build this may give you a higher BMI. However, it is a useful rough guide and we can all work out what our BMI is.

The World Health Organisation - estimates that having too high a BMI is responsible for 21 percent of the cases of ischemic heart disease, 23 percent of ischemic stroke, 58 percent of type 2 diabetes, and 39 percent of hypertension. Ischemic means your arteries have become blocked.

Obesity also increases the risk of some cancers, as well as the risk of nonfatal diseases, such as joint problems, respiratory problems and infertility.


  • Know your BMI and use it as a rough guide for your weight goals.
  • A BMI of 35 or over, without exercise, increases your risk of dying younger.
  • Being physically active reduces at least two of these risks, for heart disease and cancer - but not by as much as being a normal weight.
  • Lack of exercise may be an even bigger health risk than obesity.
  • Conversely, losing fat can partially offset the higher health risks linked with lack of exercise.
  • Obesity increases a range of other health risks, like type 2 diabetes (especially for women) as well as other negative side effects like higher levels of pain.
  • So the best combination is to maintain a normal weight and get plenty of exercise. This will reduce your risk of a range of health problems. 

Reviewed and updated by Karen Rollins April 2015. Next review date March 2020