This feature article is an excerpt from a recent Continuing Professional Development article written by Advisory Board Member, Margaret Ashwell, PhD OBE, and published by the British Dietetics Association in the December 2011 edition of Dietetics Today. Dietetics today is a monthly publication for registered dieticians in the United Kingdom. Download the full pdf article here. (PDF is in high resolution, download and save for best viewing quality.) For more information on Dietetics Today and the British Dietetics Association, please visit: http://www.bda.uk.com/
The global epidemic of obesity
Rising prevalence of obesity is a worldwide health concern as excess weight gain is certain to lead to an increased burden from several diseases, most notably cardiovascular diseases, diabetes, and cancers. 1 Current trends project 65 million more obese adults in the USA and 11 million more obese adults in the UK by 2030. This in turn would give rise to about 7 million more cases of diabetes, 6 million more cases of heart disease and stroke, and half a million more cases of cancer, for USA and UK combined. The combined medical costs associated with treatment of these preventable diseases are estimated to increase by about 55 billion dollars per year in the USA, and by about £2 billion per year in the UK by 2030.
Think about shape and not weight and focus on the ‘apples’
There are many strategies for treating overweight and obese people including diet, exercise, drugs, behavioural therapy, surgery and many combinations of all these. But it is equally important to recognise those individuals who are most likely to become obese and to identify those who will have the greatest health risks when they do. To this end, it is easier to think in terms of shape and not weight. It is now universally accepted that the health risks of obesity are more severe for people with central obesity, called ‘apples’ rather than people without central obesity, called ‘pears’.2 Central obesity usually reflects extra-large deposits of intra-abdominal fat, which seems to be more metabolically active and promotes diabetes, hypertension and other factors associated with cardiovascular and metabolic risk.
The easiest way to determine shape is to calculate, waist-to-height ratio (WHtR), which is waist circumference divided by height. If waist circumference is more than half the height, WHtR is greater than 0.5, and your patient should ‘consider action.’ If WHtR is over 0.6, your patient must ‘take action’ to avoid health risks. This advice even applies to people in the group with normal weights as assessed by BMI--those with BMI between 20 and 25.3 Use the Ashwell Shape Chart below to help you prioritise those patients who most need your help to modify diet and lifestyle for weight management.
Role of sweeteners in caloric reduction
One of the simplest ways to reduce calories in the diet is to replace the sugar in sweetened foods and drinks, either totally or partially, with non- nutritive sweeteners (NNS). Each 100g sugar contains nearly 400 kcalories. For example, to reduce personal consumption by 100 kcals per day, as currently suggested by public health officials in the UK, only 25g sugar would need to be replaced by NNS--about six teaspoonfuls.
After 40 years of NNS in the markets, we are now entering a new phase of NNS development--the natural NNS--which is in line with the drive for more natural products. This is where stevia comes in. Stevia is the first natural origin, no-calorie sweetener to be put into the market by the global food and beverage industry. It is a sweetening ingredient that is up to 400 times sweeter than sucrose.
How can your patients benefit from stevia?
Purified stevia is natural, heat stable, non-fermentable and non-cariogenic (i.e. does not promote tooth decay). Stevia is safe for people with diabetes and suitable for use by people with phenylketonuria (PKU) who cannot use the NNS aspartame because it contains the amino acid, phenylalanine.
In terms of sweetening compounds, it has a unique position because it lies right in between sucrose which is natural, but calorigenic, and other NNS which are non calorigenic but not natural.
Stevia is available to consumers in many ways. Sometimes it is the sole sweetener in the product, sometimes it is blended with other NNS, both options providing zero calorie sweetness. On other occasions it is blended with sugar to reduce calories in products like table top sweeteners or soft drinks. Today, stevia can be found in hundreds of food and beverage products from around the world.
But what happens next- is there a danger that stevia might stimulate the appetite? Luckily the answer to that question is no, certainly not in the short term. When given stevia or sucrose, both lean and overweight adults reported similar levels of hunger and satiety, and those given stevia did not increase their calorie intake at the next meal.4
In your health practice, ask your patients about their consumption of sweetened foods and beverages. For many of these, low calorie alternatives already exist. Why not suggest that they try them and point out that this is an easy way to save calories without saving on the sweetness? If they are keen to only use natural ingredients, you can tell them about stevia. Remember that six cups of tea or coffee sweetened with stevia instead of sugar will save them 100 kcalories a day.
By Margaret Ashwell, Global Stevia Institute Advisory Board Member, full version published in Dietetics Today December 2011 edition, British Dietetics Association.
The Ashwell ® Shape Chart is based on WHtR. If the shape is in the ‘chilli’ region (WHtR <0.4), the patient should “Take Care”. If in the ‘pear’ region (WHtR between 0.4 and 0.5), the patient has a healthy OK” shape. If the shape falls in the ‘pear-apple’ region (WHtR between 0.5 and 0.6), the patient should “Consider Action.” If the shape falls in the ‘apple’ region (WHtR > 0.6), the patient’s health may be at risk and should “Take Action.”
References
1. Garrow J. Treat Obesity Seriously - a clinical manual. Edinburgh: Churchill Livingstone. 1981.
2. Ashwell M. Shape: the waist-to-height ratio is a good, simple screening tool for cardiometabolic risk. Nutrition Today 2011;46:85-89.
3. Ashwell M, Gibson S. Waist to height ratio is a simple and effective obesity screening tool for cardiovascular risk factors: Analysis of data from the British National Diet And Nutrition Survey of adults aged 19-64 years. Obes Facts 2009;2:97-103.
4. Anton SD, Martin CK, Han H, Coulon S, Cefalu WT, Geiselman P, et al. Effects of stevia, aspartame, and sucrose on food intake, satiety, and postprandial glucose and insulin levels. Appetite 2010;55:37-43.