Obesity and its effect on us

Weighing scales

Author: Lesley Smyth (Obesity tutor/presenter/expert)

Obesity is defined as a ‘medical condition in which excess body fat has accumulated to the extent that it may harm health’ (NHS, 2012). It is a complex multifactorial chronic disease that develops from an interaction of genotype and the environment. Preventing and managing obesity is a complex problem with no easy straightforward answer.

Obesity has a severe impact on the health of individuals both physiologically and psychologically, with the risk of complications from secondary conditions a major concern. It’s also linked to Metabolic Syndrome (also known as syndrome X), which is a medical term for clustering of symptoms/medical disorders that, when presented together increase the risk of developing diabetes type 2 or cardiovascular disease.

In 2006 International Diabetes Federation (IDF) consensus worldwide definition is central obesity defined by waist circumference AND any two of the following…

  • Raised triglycerides
  • Reduced HDL cholesterol
  • Raised blood pressure (BP)
  • Raised fasting plasma glucose (FPG)


    BMI (KG/M2)

    Risk of secondary conditions



    Low (other health risks may be associated with low BMI)

    Healthy weight

    18.5 - 24.9


    Overweight (pre-obese)

    25 - 29.9


    Obesity, class 1

    30 - 34.9


    Obesity, class 2

    35 - 39.9


    Obesity, class 3


    Very severe

    Assessment of the health risks associated with overweight and obesity in adults should be based on BMI and waist circumference as follows…

    Weight classification

    BMI (Kg/M2)

    Men > 102cm (40’) Women > 88cm (35’)





    18.5 - 24.9



    25 - 29.9


    Obesity class


    30 - 34.9

    Very high


    35 - 39.9

    Very high



    Extremely high

    Disease risk* relative to normal weight and waist circumference

    *Increased waist circumference also can be a marker for increased risk, even for individuals of normal weight.

    Further metabolic risks associated with Obesity:

    • Hypertension - 5 fold risk in obesity (Foresight Report, 2007)
    • Coronary Heart Disease
    • Stroke - up to 6x more likely in an obese person (Lancet, 2009)
    • Certain cancers - up to 6x more likely in an obese person (Lancet, 2009)
    • Non-alcoholic fatty liver
    • Polycystic ovaries
    • Skin complications
    • Dementia
    • Respiratory disease
    • Osteoarthritis (The risk increases by 35% for every 5kg of weight. Obese individuals are 14 x more likely to have this (Grotle et al. 2008) 
    • Lower back pain 
    • Sleep apnoea
    • Stress incontinence
    • Varicose veins
    • Hernia
    • Oedema
    • Depression

    Obesity not only affects our bodies but also our society.

    • It is the fifth leading risk for global deaths
    • 2.8 million adults die each year from these conditions and it’s associated comorbidities
    • 44% of diabetes type 2, 23% of coronary heart disease and 41% of cancers can be attributed to obesity (WHO, 2013)
    • More than half of the adult UK population are overweight and one-third of people between 55 and 74 years old are classed as obese (NHS, 2012)
    • In 2012, an estimated 62% of adults (aged 16 years and over) were overweight or obese in England (BMI>25), 24.7% were obese (BMI>30) and 24% were severely obese (BMI>40). (PHE, 2014)
    • Adult obesity increased from 13% of men in 1993 to 24% in 2012 and from 16% of women in 1993 to 25% in 2012. (PHE, 2014)
    • According to a four-year study concluded in 2013 from the Health & Social Care Information Centre (HSCIC) nearly 1 in 4 adults are obese
    • The 2009 Health Survey for England (HSE) found that 1 in 6 children aged 2-10 are obese
    • The 2007 Foresight report, Tackling Obesities: Future Choices predicted that if no action was taken 60% of men, 50% of women and 25% of children will be obese by 2050
    • Obesity has a severe impact on the health of individuals both physiologically and psychologically, with the risk of complications from secondary conditions a major concern
    • Direct costs caused by obesity were estimated to be £15.8 billion in 2007 with a cost of £4.2 billion to the NHS. Predictions suggest this figure could rise to £27 billion in 2015 and forecast to more than double to £50 billion by 2050 if we carry on as we are (Foresight Report, 2007)
    • Heart and circulatory disease costs the economy £18.9 billion every year (BHF, 2013)

    Use the online BMI calculator to check your BMI


    Related Posts

    5 things to remember before exercising ...
    5 things to remember before exercising ...
    If you're new to exercise or planning on starting a new fitness programme, you should consult your GP. In my blog posts,
    Read More
    Filling in the gap
    Filling in the gap
    Fit Boutique was launched in 2014 but over the last few years we've been a bit quiet. Although I've always been here I'v
    Read More
    Getting back to fit after pregnancy - Part 3
    Getting back to fit after pregnancy - Part 3
    Weeks 6 and 7 postnatal. I’m consistently losing 2lb a week which is my target but, as life does, it’s thrown a few chal
    Read More

    Also in Wellbeing & Fitness

    The Strength Within: Why Weight Training is Essential for Women
    The Strength Within: Why Weight Training is Essential for Women

    In the realm of fitness, weight training often takes a backseat for many women. The common misconception that lifting weights will bulk them up like bodybuilders is a myth that has persisted for too long. However, the truth is quite the opposite. 

    Continue reading

    A person running up stairs
    Embracing the Vitality Within: Unveiling the Importance of Exercise

    Beyond its surface benefits of physical fitness and aesthetic improvements, exercise holds a profound significance that transcends the boundaries of the gym. It's a catalyst for transformation, a conduit for vitality, and a cornerstone of holistic health. 

    Continue reading

    Tips on keeping motivated
    Tips for staying motivated

    I’m struggling with this one myself at the moment. The weather’s cold and dark here in Essex/UK, I live in big baggy jumpers and leggings and it’s very easy to find something more important to do than exercising. So here are a few tips to help keep you motivated and consistent with your fitness...

    Continue reading