How a Western Diet Leads to Overeating and Obesity
There is no point beating around the bush, as a nation we have reached an epidemic where the prevalence of obesity has risen over the years.
We aren’t alone with this as it’s now a global issue that has become a serious one. It’s not just Western diets that have ended up with this issue. Some parts of the world are now tackling a double burden of malnutrition, where there is both undernutrition and over-nutrition, leading to obesity and non-communicable diseases co-existing within the same communities.
This is also being seen in children, where poor nutrition continues to cause nearly half of deaths in children under 5. However, low and middle income countries are also now seeing a rise in overweight and obesity in children (WHO, 2016a).
It is common knowledge that there is a global “promotion of energy-rich and nutrient-poor products” which is one of the factors of an increase in weight gain, and risk of chronic disease, especially in children (Lobstein et al., 2015).
Statistics on Obesity
- in England have risen, with up to nearly 26% of adults being diagnosed as being obese in 2014
- nearly 29% of the adult population are obese in Scotland
- 24% in Wales
- 25% in Northern Ireland
- and 23% in Ireland. (Public Health England, 2017).
More shockingly, is that there has also been an increase in the number of children being diagnosed as obese over the last 30 years. Type two diabetes, which was more commonly seen in adults, and was known as something that occurs later on in life, has been seeing a rise in children.
In 2014, 533 children were diagnosed with it, a scary statistic. It is predicted that by 2050, obesity will affect 60% of adult men, 50 of adult women, and 25% of children (Public Health England, 2017).
Health Risks Associated with Obesity
The reason this rise in prevalence is an issue, is due to obesity being linked to increases in a multitude of health risks and chronic diseases.
It is also important when looking at health risks to distinguish if someone is obese, is where they store their fat.
Excess fat stored around our abdomen (known as visceral fat) is the fat stored around our organs including the pancreas, liver and intestines and is linked to impacting health risks.
This includes, a high BMI and fat stored around the stomach, which are all factors that increase your risk of type 2 diabetes; hypertension; dyslipidaemia; coronary artery disease; non-alcoholic fatty liver disease; gout; some cancers (breast, prostate, colon, pancreas, and kidney); peripheral oedema; osteoarthritis; sleep apnoea which is caused by upper airway obstruction during sleep; and also cognitive dysfunction (Mitchell et al., 2011).
A recent meta-analysis found that obesity (increase in adiposity) has strongly been linked via evidence to cancer risks including: oesophageal adenocarcinoma; multiple myeloma; cancers of gastric cardia, colon, rectum, biliary tract system, pancreas, breast, endometrium, ovary and kidney. There are also other cancers which have a slight link, but the evidence is not strong enough (Kyrgiou et al., 2017).
Overweight and obesity are now linked to more deaths worldwide than underweight (WHO, 2016b).
How Do We Define Someone as Obese?
So, the method that is actually used to find out whether someone is obese, is based on body mass index (BMI).
This is calculated by dividing your weight in kg by height squared in m (ie. divide your weight in Kg by your height in M, then divide that answer by your height).
A BMI between 25-29.9 kg/m squared is considered overweight. It is defined as being obese if you BMI is over 30 kg/m squared.
Obesity classifications and categories can be broken down further as well. A BMI between 30-34.9 kg/m squared is class I, between 35-39.9 kg/m squared is defined as class II , and extreme obesity is class III and that is any BMI above 40 kg/m squared.
For Asians, BMI has been modified with different cut off points to assess their classification. A BMI between 23-24.9 kg/m squared is deemed as overweight, and over 25 kg/m squared is obese.
BMI is not always an accurate indicator of whether someone is obese. People who are highly muscular come up as obese, like rugby players! However, they are all in peak physical fitness, so BMI doesn’t work for everyone, but it is a good general indicator.
I remember one of my lecturers showed us a picture of a young Danny DeVito and Arnold Schwarzenegger, who incidentally have the same BMI, but if you look at them, they have a completely different body composition to each other, but both classified as obese due to BMI!
The best way as well, for measuring your abdominal visceral fat is by an MRI scan. However, this isn’t really an option for most of us, so the other way is to take a waistline measurement. To get this, find the top of your hip bone and the bottom of your ribs, place the tape between these two points and loop around your stomach. If you are a male, anything over 94cm puts your health at risk but if it’s over 102cm, it’s a high risk. If you’re a female, anything over 80cm puts you at risk, and 88cm a higher risk for your health (Diabetes, 2017).
At work (I work for the NHS on a Diabetes Prevention Programme), we use a slightly simpler method which is to find your belly button and then place two fingers above your belly button, this is roughly a similar way!
The Western Diet
There is a basic reason why we are seeing such a rise in obesity rates globally – we are, as a whole, consuming more than we are expending for energy.
Many things are now for our convenience….. we need to nip around to the shop, so we drive there; if we’re hungry but can’t be bothered to cook, then we get something already prepared for our ease. For many of us, even our jobs revolve around sitting at a desk from 9-5, with limited movement, leading a more and more sedentary lifestyle.
Pair that with the fact that many of us are now also eating more energy dense foods, most of which are processed and are high in sugar, fats and salt and contain limited nutritional benefits. This in itself is a major contributor to the rise in overweight and obesity rates.
The Western diet is defined and characterised as the overconsumption of refined sugars, high saturated and omega-6 fatty acid intake, low intake of omega-3 fat, and the over use of salt (Myles, 2014).
Evidence has suggested and shown that one of the main factors that causes obesity is the Western diet.
Our body controls our food intake through signalling pathways and these pathways also control energy balance, and reward (Argueta and DiPatrizio, 2017).
A study which looked at mice found that when mice were fed on a Western diet, this lead to the activation of specific signalling pathways, which promote hyperphagic responses (this means there is an increased appetite and frequency in consumption of food). The mice on the Western diet also had an increase in calorie intake, size of meal and the rate of feeding, in comparison to the mice which were fed on a standard diet (Argueta and DiPatrizio, 2017). It is suggested that the activation of signalling pathway for reward, is activated during the Western diet and may be one of the factors that leads to obesity.
The Western diet leads to positive reinforcement with certain parts of the brain recognising it as food reward (Argueta and DiPatrizio, 2017). It was found that with the mice that were exhibiting hyperphagia and were obese from the Western diet, when the specific pathways that are involved in this were inhibited, it led to the mice resuming a normal diet intake, even when they were consuming the Western diet. It was concluded that this may be a safe therapeutic approach for treating overeating due to the Western diet, and may be a safer alternative to other approaches which have caused psychiatric side effects, including depression and suicide (Argueta and DiPatrizio, 2017). This is still a study conducted on mice but it shows promising transferrals to a potential treatment for us.
In the UK, we have some of the highest rates of obesity in Europe and with this it holds a multitude of issues which we have discussed above, as well as general aches and pains.
It’s not just the increased risk of non-communicable diseases but also our diet has a negative impact on our immune system, making us more likely to get ill and also causes our body to struggle to recover from infections.
In 2011, a white paper was published in the UK, called “Healthy Lives, Healthy People: A call to action on obesity in England” (Department of Health, 2011). This policy paper aimed to try and reduce the rates of excess weight in both adults and children. What they aimed to do was empower individuals to be able to make their own informed decisions through feedback on BMI, through Change4Life (which also has an app), trying to get companies to reduce their salt and sugar levels, and trying to get people active.
It’s not just the UK who are trying to target and change obesity levels. The World Health Organisation has also developed the “Global Action Plan for the Prevention and Control of Non-Communicable Diseases 2013-2020”.
Another method for looking at the amount of abdominal fat we have is by measuring your waist to height ratio, which in general, you want to keep your waist less than half your height and may be more transferrable to all individuals (Ashwell et al., 2014). Click here to see the waist-to-height ratio chart. BMI is good for population level trends but not always for individuals.
In a society where we have developed so we don’t need to do as much movement in our day to day life, we need to make sure that we are all exercising. It is recommended that we get 150 minutes of moderate, aerobic activity every week, something that increases our heart rate and gets us sweating (NHS, 2015).
It is important that we break up our daily activity, especially if we do spend most of it sitting down, with activity and movement. Instead of going in the elevator, take the stairs; if going on the bus, get off the stop before you’re meant to; if you’re sat down watching tv, get up and walk around. It’s important to just keep moving.
It’s important to try and eat lots of fruit and vegetables, as well as reducing or being aware of the amount of processed foods you are eating and making sure that you are eating lots of fresh produce.
When possible, cook from scratch. This means that you can control the amount of sugar and salt you put into things, as well as avoiding preservatives and additives. For example, if we take a tomato sauce for pasta, a packaged one may contain lots of sugar and salt but when you make your own, you can use a fraction of the salt and maybe no sugar!
Argueta, DA. And DiPatrizio, NV. (2017). Peripheral endocannabinoid signalling controls hyperphagia in western diet-induced obesity. Physiology & Behaviour, 171, pp. 32-39. Available here.
Ashwell, M. Mayhew, L. Richardson, J. and Rickayzen, B. (2014). Waist-to-height ratio is more predicative of years of life lost than body mass index. PLOS one. Available here.
Department of Health. (2011). Healthy Lives, Healthy People: a call to action on obesity in England. Department of Health, HM Government. Available here.
Diabetes. (2017). How to measure your waist. Diabetes.co.uk. Available here.
Kyrgiou, M. Kalliala, I. Markozannes, G. Gunter, MJ. Paraskevaidis, E. Gabra, H. Martin-Hitsch, P. and Tsilidis, KK. (2017). Adiposity and cancer at major anatomical sites: umbrella review of the literature. The British Medical Journal, 356. Available here.
Lobstein, T. Jackson-Leach, R. Moodie, ML. Hall, KD. Gortmaker, SL. Swinburn, BA. James, WPT. Wang, Y. and McPherson, K. (2015). Child and adolescent obesity: part of a bigger picture. The Lancet, 385(4), pp. 2510-2520. Available here.
Mitchell, N. Catenacci, V. Wyatt, HR. and Hill, JO. (2011). Obesity: overview of an epidemic. Psychiatric Clinics of North America, 34(4), pp. 717-732. Available here.
Myles, IA. (2014). Fast food fever” reviewing the impacts of the western diet on immunity. Nutrition Journal, 13(61). Available here.
NHS. (2015). Physical activity guidelines for adults. NHS Choices. Available here.
Public Health England. (2017). UK and Ireland prevalence and trends. Public Health England. Available here.
WHO. (2016a). Double burden of malnutrition. World Health Organization. Available here.
WHO. (2016b). Obesity and overweight. World Health Organization. Available here.
About Lucy Bee Limited
Lucy Bee is concerned with Fair Trade, ethical and sustainable living, recycling and eating close to nature with additive free products for health.
Members of the Lucy Bee team are not medically trained and can only offer their best advice. Any information provided by us is not intended to diagnose, treat, cure or prevent disease.
Please note you should always refer your health queries to a qualified medical practitioner.