With more and more people being diagnosed with diabetes every year, it’s definitely a risk to wake up to if you are overweight. It’s believed that obesity accounts for 80-85% of the risk of developing type 2 diabetes. The charity Diabetes UK suggests that up to 80% of cases of type 2 diabetes can be delayed or prevented by making simple diet and lifestyle changes.
In addition to being overweight, other risk factors for diabetes include:
- Your ethnicity; people from African-Caribbean, Black African, Chinese or South Asian backgrounds over the age of 25 are more at risk
- Your age; risk increases past age 40 for people from other backgrounds
- Family history; sibling or parent with diabetes
- Medical history; previous heart attack, stroke, or polycystic ovaries (PCOS)
- Medical diagnosis; being diagnosed with ‘pre-diabetes’ (sometimes called ‘impaired fasting glycaemia’ or ‘impaired glucose tolerance’) and/or having high blood pressure
- Pregnancy-related risks; gestational diabetes during pregnancy, and/or giving birth to a baby over 10lbs (4.5kg)
This article refers to type 2 diabetes, which accounts for around 90% of people with diabetes. This type of diabetes is different to type 1 diabetes which is an autoimmune disease often diagnosed in childhood, and requires insulin treatment from the outset. With type 2 diabetes, the pancreas either isn’t producing enough insulin to maintain normal blood sugar levels, or the body isn’t able to use the insulin it’s producing – known as ‘insulin resistance’. Often people will start by being ‘diet controlled’, and may move on to medications or even insulin as the disease progresses over time.
Why does being overweight increase my risk?
Whilst carrying excess weight is a well-known risk factor for type 2 diabetes, scientists are still not sure about the exact mechanisms by which being overweight or obese cause diabetes.
It’s a myth that diabetes is caused by eating too much sugar or sugary foods. The fact is that being overweight is a big risk factor of developing diabetes, and eating too much sugar or sugary food is linked to weight gain. By regularly eating foods high in sugar (and fat) like cakes, biscuits, pastries, chocolate, and sugary drinks, you increase your calorie intake, and thereby increase your chances of gaining weight.
However, although body mass index (BMI) is an important measurement, it’s perhaps not the most important factor. What really increases your risk of diabetes is your body shape; the amount of weight (fat) you carry around your middle and upper body. You may have seen this measurement referred to as ‘waist circumference’. It is quite possible for someone to have a healthy BMI, but have too large a waist measurement. This means if you are an ‘apple shaped’ person – prone to storing more fat around your middle (and less around your hips and thighs), you may be more at risk of diabetes than a ‘pear shaped’ person (who stores less fat around their middle and more around their hips and thighs) even with the same BMI.
Being overweight, and in particular having a large waist circumference indicates you’re carrying too much fat. Fat stored centrally, around key organs like your heart, liver and pancreas, can result in insulin resistance – where your fat cells have become resistant to your natural insulin production. This results in too much sugar staying in the blood stream, rather than entering your fat cells.
The following table shows the measurement cut-offs for significantly increased risk of diabetes (and cardiovascular disease). If you haven’t already done so, try measuring yourself (instructions in the final section) – if your waist is higher than these below, then you really need to take stock:
|White||94cm (37 inches)||80cm (31.5 inches)|
|Black||94cm (37 inches)||80cm (31.5 inches)|
|Asian||90cm (35 inches)||80cm (31.5 inches)|
Table taken from www.diabetes.co.uk.
How can losing weight help?
Research has shown that losing as little as 5-10% of your weight can result in significantly reducing insulin resistance.
If you already have diabetes, whilst you can’t reverse it, there’s good news for you too on the benefits of weight loss front. Losing 5-10% of your body weight can significantly reduce your HbA1c, and can also reduce your blood pressure and cholesterol if these are raised too.
Losing over 10% of body weight has even more significant improvements.
Research suggests that obese people (BMI over 30) are 80 times more likely to develop type 2 diabetes than those with a BMI of less than 22 – that’s a staggering statistic! A BMI of 22 may seem like a future pipe dream – a long way off, but hopefully the fact that losing just 5% will have a big difference too will motivate you to keep going. For a 15 stone person, this means losing just 10lbs, which is a much more realistic short-term goal.
What else can you do to help reduce your risk?
The following tips will help you to understand your risk factors and how to start making changes.
- Be aware of your risk factors – whilst you can’t change some of your risk factors (such as age or ethnicity), it’s still important to review the risk factors for diabetes, especially those you can change. You could consider getting an NHS Health Check with your GP or Practice Nurse. The NHS Choices website also has a type 2 diabetes self-assessment tool.
- Know your numbers – Most people tend to weigh themselves regularly, but do you measure your waist circumference as well? You waist size is not necessarily your trouser size. To measure yourself, you will need to find the mid-point between the bottom of your rib cage and the top of your hip bone; measure around this point, and take the best of three measurements. Measure this monthly, alongside your usual weekly weights. Some people see really positive reductions in waist circumference without significant reductions in weight, which can be motivating.
- Decide on the best approach to weight loss – you will need to make changes to your diet and get the right support in order to lose weight and keep it off for good. How you do this is the tricky bit! But trying a Slim & Save programme might be a good option for you.
- Slash your sugar and fat – if you have already been diagnosed with diabetes or pre-diabetes, now is the time to really take action. The British Heart Foundation have produced a labelling ‘decoder’ – a useful tool that can be used to help you choose lower fat and lower sugar foods, by reviewing the nutrient content per 100g of food. It’s a really useful way to start looking at reducing your intake. You can download the PDF from here.
- The new Change 4 Life Sugar Smart App is another really useful tool to help you cut back on your sugar intake.
- Exercise – has a big role to play in reducing risk of diabetes. Whilst increasing you exercise levels can help you lose weight, regular exercise is also known to increase your body’s sensitivity to insulin (thereby reducing insulin resistance). Just 30 minutes of moderate-intensity exercise a day can help you achieve this benefit.
Written by Annemarie Aburrow RD BSc (Hons) PGDip, Slim & Save Dietitian.