INTRODUCTION

“Chocolate lifesaver – from cancer to dementia” written by Fiona Macrae of the health section of the Mail Online in March 2007 [1]

This article concerns the possible benefits of compounds called flavonoids found in chocolate in relation to Cancer, Diabetes, Heart Disease and Dementia –[chocolate] “could prove to be as important to medicine as penicillin” [1].

A study of the central American Indian Kuna tribe whose diet is exceptionally rich in cocoa, showed they rarely suffer from high blood pressure and have lower rates of cancer, heart disease, and diabetes. It suggests this is due to their high intake of epicatechin (a flavonoid), which they get from “drinking up to five cups of cocoa a day” [1].

It is believed that flavonoids in chocolate could be used in future to develop preventative medicine or dietary supplements, hence is an interesting area of research.

DIABETES

Diabetes mellitus is a disease of disordered glucose metabolism, resulting in hyperglycaemia. Blood glucose levels are controlled by a complex interaction of chemicals and hormones in the body, including insulin, made in the beta cells of the pancreas. Diabetes develops due to a diminished production of insulin (in type I) or resistance to its effects (in type II and gestational), both of which lead to hyperglycaemia. The majority of new cases will be Type 2 diabetes, attributable to the ageing population and rapidly rising numbers of overweight and obese individuals.

Due to the absence of insulin and inability of cells to absorb glucose in diabetics, the consumption of glucose containing chocolate, would seem an unlikely weapon against diabetes. However, new research shows that eating dark chocolate reduces the risk of damaging changes in the body that can lead to the condition [1].

The Daily Mail article states that “Diabetes deaths were six times less common” in reference to the diabetes related mortality rate of the Kuna people on the Island of San Blas compared to that of on the mainland of Panama [1].

However the data has been age adjusted, therefore is misleading as it is not actually six times less common: “Deaths due to diabetes mellitus were much more common in the mainland (24.1 ± 0.74) than in the San Blas (6.6 ± 1.94)” [13].

In a study by Song et al. it was found that the flavonoids in chocolate “may prevent the progressive impairment of pancreatic β-cell function due to oxidative stress and may thus reduce the occurrence of type 2 diabetes” [14]. However, the results did not support this hypothesis, and although the modest inverse association with intake of flavonoids cannot be ruled out, it is not conclusive enough to state that high intake of flavonoids reduces the development of diabetes.

In conclusion, our findings have shown that although flavonoids may have a beneficial effect on some aspects of health, their impact on diabetes is inconclusive.

CANCER

Cancer is caused by the uncontrolled proliferation of cells in the body. Cancerous cells grow without instruction from the body, do not stop growing, do not die or age and feed themselves by angiogenesis. There are over 200 different types of cancer. Currently 1 in 3 people will develop cancer in their lifetime, hence prophylaxis and anti-carcinogen research is essential.

Cocoa's anti-carcinogenic propertiesCocoa has proven to have anti-carcinogenic effects due to antioxidant activity. They are believed to reduce carcinogenesis by removing growth factors and contributing factors such as inflammation. Antioxidants have been shown to “inhibit chemically induced carcinogenesis” and “exert antioxidant activity in humans” [4]. Oxygen radical damage to DNA is a well-recognised effect of carcinogenic agents. Antioxidants slow down and/or inhibit oxidation by removing free radicals. Blocking oxygen radical production may provide a major protective effect against carcinogenesis [5].

PolyphenolsThe antioxidants in cocoa are polyphenols [6] which may reduce the risk of cancer. Research shows that “polyphenols act as antioxidants in vitro by scavenging reactive oxygen and nitrogen species and chelating redox-active transition metal ions” [7]. They function as antioxidants through inhibition of pro-oxidant enzymes, such as inducible NO synthase, COXs, and antioxidant enzymes. These contribute to carcinogenesis. By activating these processes, polyphenols have been shown to induce apoptosis, inhibit angiogenesis, and inhibit growth thereby blocking carcinogenic cell cycle progression.

Cocao’s anti-inflammatory propertiesPolyphenols have also been found to prevent inflammation. Inflammation clears damaged cells including DNA damaged cells but can also cause DNA damage to cells leading to the proliferation, survival and migration of cancerous cells via mediators such as prostaglandins, histamine, cytokines and reactive oxygen species such as Nitric Oxide. The COX and NF-κB pathways are also implicated in malignant tumour formation [8], which can be inhibited by polyphenols.

Flavonoids: The best studied of the polyphenols. They have been found to enhance detoxification, direct antioxidant action to the initiation stage of carcinogenesis and prevent DNA-carcinogen interaction [9],[10]. Two flavonoids in particular have been found to have anti-carcinogenic benefits:

1. Catechins: Found abundantly in chocolate. In research it has been found that catechins reduce carcinogenesis in vitro and in particular to have benefits for human breast carcinoma [11] . Epigallocatechin-3-gallate has protective properties against UV radiation-induced damage and skin tumour formation, preventing skin cancer [12].

2. Quercetin: Has been found to inhibit the inflammatory mediator histamine.Chocolate containing polyphenol flavonoids hence has been shown to have antioxidant, anti-inflammatory, and in consequence anti-carcinogenic properties, and thus could be a prophylactic treatment of cancer.

CORONARY HEART DISEASE

• CHD occurs when the coronary arteries are blocked by plaques (atheroma) of fatty and scar tissue. A short duration of hypoxia caused by the blockage will kill myocardial cells.• One risk factor of CHD is high blood pressure. High blood pressure can cause lesions in the endothelium of the coronary arteries. This damage triggers aggregation of platelets and, eventually, a block [15].• Flavonoids in chocolate reduce plaque formation and hence the risk of CHD [16]. • In a study by Pearson et al. “16 healthy adults consumed aspirin (81 mg), cocoa (as a beverage), or aspirin plus cocoa”. Results showed that chocolate containing polyphenols was found to lower the levels of leukotrienes by 29% and increase the levels of prostacyclin by 32%. Leukotrienes stimulate vasoconstriction and platelet aggregation. Prostacyclins are vasodilators and inhibit platelet aggregation. It was, however, found that aspirin has the most successful and long-lasting antiplateleteffect, lasting for days rather than hours [17].• Also, in cocoa feeding trials, chocolate has been found to increase HDL (good) cholesterol. HDL is believed to remove cholesterol from plaques in arteries and hence decreases blood pressure [16].

HOWEVER

There was only a small sample size of 16 subjects and a short duration of Flavonoid action. Leukotrienes and Prostacyclins play a small role inplatelet aggregation. Also LDL increase clearlyoutweighs antiplateletfunction and HDL action [18].

Produced by: Amy Balmer, Ashley Cottrell, Charlotte Gould, Maximillian Julve, Madiha Lightwood, Jonathan Noble, Sadia Rahman, Humera Sheikh, Seema Vawda

[20]

PET Scan of dementia (top) compared to normal patient [20]

Table 1. showing the various foods monitored in the study [22].

DEMENTIA

Dementia is a general term for a disease of the brain characterised by the progressive loss of higher intellectual and cognitive functions. Symptoms include memory loss, change in personality, inability to learn and understand new information and disorientation. There are numerous potential causes:

Dementia is most common in the elderly population; 1 of 20 people over 65 and 1 of 5 over 80 year olds suffer some form of it.

Preventative measures of dementia have been widely investigated. One such measure is the use of flavonoids found in chocolate as studied by Commenges et al. [22].

The Daily Mail article relies on this paper to infer that chocolate can reduce the risk of developing dementia [1]. The paper took a cohort of 1375 people over the age of 65 in south-west France and monitored them from 1991-1996. At the end of this time, 66 of the participants had developed a form of dementia (46 developed Alzheimer's, 20 developed other types).

Questionnaires and interviews were given at the start of the study and at intervals throughout to assess how much of their diet comprised those foods seen in

Table 1. Each food was measured for its content of the five major flavonoids including quercetin.From this, they concluded that the intake of flavonoidswas inversely proportional to the risk of developing dementia.

HOWEVERIn this study, chocolate was not explicitly considered –only the major flavonoids found in many foods were, thus its specific effect on flavonoid intake is not clear. The paper also only applies to those over 65 years of age – no mention made of younger people. The article also only concludes that more research into this area should be done before firm conclusions can be drawn.

• Degenerative diseases such as Alzheimer's (most common, afflicting an estimated 62% of all dementia suffers) and Pick’s• Vascular diseases• Head trauma• Even vitamin deficiency

REFERENCES

1. Daily Mail Online, Chocolate lifesaver - from cancer to dementia, 2007. Available at: http://www.dailymail.co.uk/health/article-441600/Chocolate-lifesaver--cancer-dementia.html [accessed 03/10/08].2. The Healthy Chocolate Revolution, 2004, Available at: http://darkcocoariches.info/images/img_activ.gif[accessed 17/10/08]3. Flavonoids, Wikipedia, 2008, Available at: http://upload.wikimedia.org/wikipedia/commons/2/20/Epicatechin.png, [accessed 20/10/08]

CANCER:4. Kang, N.J., Lee, K.W., Lee, D.E. et al. Cocoa procyanidins suppress transformation by inhibiting mitogen-activated protein kinase kinase. Journal of Biological Chemistry, 2008, 283(30), pp. 20664-73. 5. Ruddon, R.W. Cancer Biology. 4th ed. Oxford University Press, USA, 2007.6. Arts, I.C. & Hollman, P.C. Polyphenols and disease risk in epidemiologic studies. American Journal of Clinical Nutrition, 2005, 81(1 Suppl), pp. 317S-325S.7. Frei, B. & Higdon, J.V. Antioxidant activity of tea polyphenols in vivo: evidence from animal studies. Journal of Nutrition, 2003, 133(10), pp. 3275S-84S.8. Hull, M.A., Booth, J.K, Tisbury, A. et al. Cyclooxygenase 2 is up-regulated and localized to macrophages in the intestine of Min mice. British Journal of Cancer, 1999, 79(9-10), pp. 1399-405. 9. Surh, Y. Molecular mechanisms of chemopreventiveeffects of selected dietary andmedicinal phenolicsubstances. Mutation Research, 1999, 428(1-2), pp.305-27.10. Sale, S., Tunstall, R.G., Ruparelia, K.C. et al. Comparison of the effects of the chemopreventive agent resveratrol and its synthetic analog trans 3,4,5,4'-tetramethoxystilbene (DMU-212) on adenoma development in the Apc(Min+) mouse and cyclooxygenase-2 in human-derived colon cancer cells. International Journal of Cancer, 2005, 115(2), pp. 194-20111. Mittal, A., Pate, M.S., Wylie, R.C. et al. EGCG down-regulates telomerase in human breast carcinoma MCF-7 cells, leading to suppression of cell viability and induction of apoptosis. International Journal of Oncology, 2004, 24(3), pp. 703-10.12. Katiyar, S., Elmets, C.A. & Katiyar, S.K. Green tea and skin cancer: photoimmunology, angiogenesis and DNA repair. Journal of Nutritional Biochemistry, 2007, 18(5), pp. 287-96.

DIABETES:13. Bayard, V., Chamorro, F., Motta, J., et al. Does flavanol intake influence mortality from nitric oxide-dependent processes? Ischemic heart disease, stroke, diabetes mellitus, and cancer in Panama. International Journal of Medical Sciences, 2007, 4(1), pp. 53-8.14. Song, Y., Manson, J.E., Buring, J.E. et al. Associations of dietary flavonoids with risk of type 2 diabetes, and markers of insulin resistance and systemic inflammation in women: a prospective study and cross-sectional analysis. Journal of the American College of Nutrition, 2005, 24(5), pp. 376-84.

CORONARY HEART DISEASE:15.Michelson, A.D. Platelets, 2nd Ed., Elsevier Inc., USA, 200316. Ding, E.L., Hutfless, S.M., Ding, X. et al. Chocolate and prevention of cardiovascular disease: a systematic review. Nutritional Metabolism (London), 2006, 3, pp. 2.17. Pearson, D.A., Paglieroni, T.G., Rein, D. et al. The effects of flavanol-rich cocoa and aspirin on ex vivo platelet function. Thrombosis Research, 2003, 106(4-5), pp. 191-7.18. Holt, R.R., Schramm, D.D., Keen C.L. et al. Chocolate Consumption and Platelet Function. Journal of the American Medical Association. 2002, 287(17), pp. 2212-2213.19. Haemstasis, 2007, Available at: http://www.haemostasis.se/resource/3.Platelet-plug-formation.jpg [accessed 17/10/08]

DEMENTIA20. Geriatrics & Aging, 2005, Available at: http://www.geriatricsandaging.ca/ga_folder_new/may_2001/dementia.gif [accessed 31/10/08].21. Science Clarified, 2008, Available at: http://www.scienceclarified.com/images/uesc_04_img0178.jpg, [accessed 31/10/08].22. Commenges D, Scotet V, Renaud S et al. of flavonoids and risk of dementia. European Journal of Epidemiology.2000, 16, pp. 357-363.

CONCLUSION23. BBC News Online, Chocolate's double-edged health message, 2001, Available at:http://news.bbc.co.uk/1/hi/in_depth/sci_tech/2001/glasgow_2001/1521982.stm [accessed 01/11/08]24. BBC News Online, Dark chocolate may be healthier, 2003. Available at:http://news.bbc.co.uk/1/hi/health/3185363.stm [accessed 01/12/08].

CONCLUSION

•Flavonoids in cocoa could have positive health affects and could have huge implications for prevention of illnesses. Dark chocolate is better because of the effect of milk on flavonoid uptake [23].

•Most commercially available chocolate bars contain very small amounts of flavonoids, which are swamped by milk, sugar and fats which can lead to increased cholesterol intake [24].

•Fruit and vegetables contain much higher levels of flavonoids and antioxidants than chocolate as well as many other beneficial vitamins and minerals without the fat though this does not make such sensational news.

•It should be noted that the research behind the Daily Mail articleis funded by MARS.

•The BHF does not endorse regular chocolate snacking to protect our hearts. And “advising people to eat chocolate regularly for their hearts' sake is reckless” [24].

•Articles such as this one, especially headlines, which grab the public's attention, are evidence that one should not believeeverything we see and hear in the media.

WHAT ARE FLAVONOIDS?

Figure 1. Flavonoids are the largest of the plant polyphenols. They are widely distributed in plants. Scientists have identified several cocoa flavonoids, including epicatechin, catechin, and their oligomeric forms, and their antioxidant properties. [3]

[2]

Prostate cancer – The PSA test

The Prostate GlandThe prostate is an exocrine gland of the male reproductive system

The main function of the prostate is to store and secrete a slightly alkaline fluid, contributing from a quarter to a third of the semen. This fluid helps to neutralise the acidity of the vaginal tract and prolong the lifespan of sperm

The prostate also contains smooth muscle that help to expel the semen during ejaculation

The healthy prostate is about 3cm across and surrounds the urethra inferiorly to the bladder (figure 1)

Prostate cancer is the commonest cancer in men within the UK, with nearly 35,000 new cases each year. The lifetime risk of being diagnosed with prostate cancer is 1 in 14 (reference 1).

Conclusion

What else is available?

The PSA test

Discussion

While the PSA test is one of the first line diagnostic procedures for finding prostate cancer, there are other methods for diagnosis.

A confirmed high PSA reading will be followed up by a digital rectal examination. The doctor will insert a gloved finger into the rectum to feel for any abnormalities. If cancer is present then the prostate may feel hard and rough.

Another test includes trans-rectal ultrasound, this involves insertion of a probe into the rectum to get an ultrasound image of the gland. A biopsy is often taken at the same time.

10 samples of tissue are often taken from the prostate in biopsy for microscopic examination. This yields a false negative 5-10% of the time though, meaning a repeat biopsy is required for negative results (ref 13).

A novel genetic test is available to complement the PSA test, however this test is expensive (over £200). This test requires a prostate massage with 10ml of urine sampled afterwards. The PCA3 gene is measured in the sample. This gene is over-expressed specifically in prostate cancer (ref 14).

Prostate specific antigen (PSA) is a glycoprotein produced by prostate gland epithelia.

Blood serum PSA levels may rise with prostatic disease, including cancer, due to increased production of PSA and by architectural changes in the prostate allowing better access to the circulation.

There may be many causes for increased PSA levels other than prostate cancer, including acute urinary retention and acute prostatitis (REFERENCE 3).

In the USA the test costs around $50-$80 (£36-£58). It is estimated that if every male over the age of 50 had the PSA test it would cost $28billion (£20billion) per year (Reference 4)

Methodology of the PSA test

Future Research

Figure 1: The anatomy of the male reproductive system showing location of the prostate gland. Notice its proximity to the rectum. (Image taken from reference 2)

Prostate cancer is often discovered with a PSA test but there is concern about the accuracy of this test.

The use of PSA testing also varies considerably between the UK and the USA.

Through this poster we aim to discuss the benefits and drawbacks of aggressive screening for PSA and some of the reasons why there is such a discrepancy between testing between the UK and the USA.

In the UK, the PSA test costs around £10 per person (ref 5). According to cancer research UK, “The current and annual cost of treating prostate cancer to the NHS in England and Wales is likely to exceed £55million (ref 6)

Figure 2: Image showing the percentage chance of false positive and negative PSA test results and number of prostate cancers detected

(taken from reference 7)

The PSA test is a blood test

It can take up to 2 weeks to get the results (reference 8)

The normal range for PSA blood serum levels is between 0.0 – 4ng per millilitre of blood (ref 9)

In the laboratory, the prostate specific antigens are detected by a method called the monoclonal antibody technique. In this method, the antibody that the prostate specific antigen will bind to is produced. (REF 10)

Mice are used to isolate the antibody-forming cells. These antibody-forming cells are then mixed with a tissue culture and allowed to replicate until sufficient numbers are produced. After various safety tests are carried out, the antibodies can be isolated from the tissue culture.

When the patient’s blood sample is received, the prostate specific antigens present in that sample will bind to isolated antibodies. Depending on the concentration of PSA present in the sample, more or less antibody-antigen complexes will form.

There has been much debate across the world on whether the PSA test is a useful test or discriminant of prostate disorders. There are many advantages of the test, but increasingly worrying are the possible drawbacks of including the PSA test as part of a prostrate cancer screening process. Some of the advantages and disadvantages of the test are described in the table below.

(Adapted from McMillan Cancer Trust)

As soon as the PSA test was introduced in 1987, it soon became part of the preventive health care system in the USA, for men over the age of 40. Though there was some debate at the time, on the value of the test, it is now understood the views of the PSA test were based on modelled data. Recent studies reported in the NEJM (Reference 15, 16), illustrated that American men who received annual PSA tests did not have a reduced rate of death from prostate cancer. The figures produced from the studies, therefore determine the PSA test to be ineffective in prostate cancer prevention.

The feeling that the PSA test brings about unnecessary worry on the patient is now ever growing. False- positive results have also led to individuals being wrongly diagnosed and treated. With the high number of false- positive results and the ineffectiveness of the PSA test in preventing death from prostrate cancer is it now time for the American health system to abandon the PSA test and the consequent Prostrate Cancer screening programme. Data suggests America might need to.

In European countries, like the UK, the PSA test is only suggested by a GP when a patient is showing other symptoms of prostate cancer such as urgent or very frequent need to urinate, or difficulty starting and stopping urination (NHS Choices).

The prostate specific antigen-antibody complexes that are formed can be detected by radioactive markers, so that when the antigen binds to the antibody, the antibody undergoes a conformation change and this emits some form of radiation which can be detected. The amount of radiation detected gives quantitative results as to how much PSA is present in that blood sample. (REF 11)

Figure 3: This shows the production of antibodies from mice. These antibodies can then be used to detect the amount of PSA present in the blood sample (Image taken from reference 12)

There are several new tests available for the detection of prostate cancer. A Gene expression test based of 4 genes can be used to detect prostate cancer with a 93% sensitivity. This test could lower the number of false negatives of prostate biopsy and reduce the necessity for invasive procedures in prostate diagnosis (ref 17).

The PCA3 test is also likely to be used more widely in the diagnosis of prostate cancer as it is less invasive than biopsy and more sensitive. This test is expensive though (ref18).

Peter JarvisJoge-Jossy TonisonJonathan NesarajSeema Vawda

A false-positive result can lead to unnecessary follow-up testing that is more invasive, i.e., multiple biopsies.

The test is a quick, simple and painless procedure involving taking a sample of blood for testing in a lab.

Men over the age of 75 may not benefit from the test because the prostate is generally very slow growing and treatment is unlikely to lengthen their lives.

The test may contribute to significant reduction deaths from prostate cancer.

The test does not distinguish between prostate cancer and other prostate problems such as infection.

Early detection before the cancer has spread outside the prostate provides men with more treatment options and a better chance for a cure.

High rate of false-positive results.The test detects cancer 5 to 10 years earlier than digital rectal exams (DREs).

Significant number of false negatives. In 1 out of 5 cases, the PSA test comes back 'normal' with PSA levels in men with early prostate cancer.

Prostate cancer can be detected by the test long before symptoms present themselves.

DisadvantagesAdvantages

Overall, data suggests the PSA test should not be part of a prostrate cancer screening programme in the USA. However, the truth is many American patients and doctors are happy with the introduction of the PSA test as it can inform them of a possible health problem.

Due to the inaccuracy of the PSA test, better methods for detecting prostate cancer are needed.

Mixed messages in media portrayal of obesity

The article stated that thinking makes you want to eat more. The intake of 14 students was measured after relaxing, a summarizing task, and computerised memory test. It was found that the students consumed 203 and 253 more calories after the summarising and computer tests respectively when compared to the rest condition.

Scientific SummaryThe study attempted to investigate the impact of knowledge-based work in energy intake and glucose homeostasis. The calorific intake of 14 female students was measured after 3 different test conditions: resting, writing a summary, and performing computerised tests. Plasma glucose, insulin and cortisol levels were also measured. It was found that the energy intake for the summarising and computer tasks compared to the rest condition was increased by 848kJ and 1057kJ respectively. The cortisol levels were found to be significantly higher in the knowledge-based work conditions, and fluctuations in glucose and insulin levels were observed. The study concluded that ‘knowledge-based work is thought to be a stimulus that has the potential to alter the precision of the regulation of carbohydrate balance and favour an increased caloric intake as a mechanism of maintaining homeostasis”.

Obesity and the MediaObesity has become a regular staple of media coverage, on any given day it would be difficult not to find some type of coverage on obesity, in the news. This coverage and the increased awareness has led to obesity becoming a public health concern, but do the statistics support this coverage? As can be seen in the two casestudies, the media portrayal of an issue does not always line upwith the reality of the science. The social issues research centre (SIRC) was commisioned in 2003 by the government to investigate this very claim, it was granted access to all government data from the annual Health Survey for all of the UK for the prior 10 years. In the 10 years of the study the BMI of both boys and girls did notincrease in a significant way and the overall prevalence of obesity did not increase significantly (Figure 5).

Clearly the data does not reflect the pandemic levels of child obesity reported. The latest data, released in the 2006 Health Survey data results, shows the percentage of overweight children has decreased or remained steady since 2000 (Health Survey Data 2006).

Within adult populations the SIRC did find a significant increase in BMI between 1993 and 2003 (Figure 5). The 2006 Health survey with overall prevalence of adult male obesity within all age groups averaged at an increase of 22.2 % to 23.7%, though it is worth mentioning that within 3 of the 7 age categories the rate decreased (National Health Survey Data 2006). In females an increase in overall prevalence was noted from 23.0% to 24.2%. Within all age categories except 16-25 female obesity rates have increased (National Health Survey 2006).

Without question obesity rates within adult populations is on the rise, but it has yet to be proven with any certainty that they are increasing significantly within children, this is not reflected within media coverage however (Figure 6). Many government initiatives and policies reflect this high reported childhood obesity rates even if they are not accurate. In the 2003 report on obesity in the UK, the SIRC concluded that this high rate of investment in prevention of childhood obesity could not at this point be supported by actualscientific data, and that obesity rates within children were not rising at the levels that were being reported in the media (SIRC 2003).

Inverse Pyramid WritingJournalists can get away with writing outrageous headlines by simply removing some information and not giving whole truths. The media use many ways to rope readers in and make a point quickly and succinctly. The purpose of these techniques is to drive home immediately the theme of an article in such a way that the reader’s interest may be captured.

One of the most common and most successful types of writing is referred to as “inverse pyramid writing”. Whilst an essay or academic paper would place a summary at the end of a paper, these articles would do the opposite, by starting with the summary. This methodology is important as it means all the essential facts are communicated at the beginning of the article and the reader can therefore stop reading at any point in the article and still come away with the majority of the useful and intended information. In this case, the broader the point, the more important the information and the further down the article it needs to go. As an illustration of this, the beginning of this explanation has been written in such a style hopefully meaning that your eye was caught as you saw the rather bold title and your continuing desire to read was due to a gradual release of information, getting more detailed down the paragraph. This inverse style itself also has the ability to allow emergency cuts by an editor since the bottom few lines are intended to be supplementary rather than necessary. Clearly providing a wealth of informative articles is not high on the media’s agenda.

Limitations of the study•The paper refers to the mental tasks as “knowledge based”, none of the activities actually relied on the use of knowledge. •The study was only tested on a very small sample of women, aged 20 to 30 so can not be generalised to the whole population. •The study also took place between May and October, allowing possible seasonal variations.•There was no randomisation of order that the subjects performed each task, resulting in a possible learned response and un-blinding of the study.

below).

Scientific summaryExperiment 114 males (av. BMI 22.5) took part in an experiment to test whether comparing new food with recalled food affects intake. Participants recalled their lunch today and their lunch yesterday on two days in random order. They rated bowls of popcorn and ate freely any leftovers. They scaled hunger, desire to eat, and fullness in a questionnaire. An ANOVA was used to determine variance and amount eaten was calculated. It was found that those who recalled today’s lunch ate less than those who recalled yesterday’s lunch. No effect was found of condition on rated liking of popcorn types suggesting compared palatability does not affect food intake.Experiment 2 73 females (av. BMI 21) took part in a study to test whether the effect of food recall is dependent on dietary traits. Four groups were created.1.Low restraint / low disinhibition2.Low restraint / high disinhibition3.High restraint / low disinhibition4.High restraint / high disinhibitionParticipants were subdivided into lunch today and lunch yesterday groups. The experiment followed the procedures above. Intake wasnot affected by condition, restraint, or disinhibitionoverall, however in lowdisinhibition participants there was a significant decrease in intake in those whorecall today’s lunch compared to those who recalled yesterday’s lunch. Experiment 347 females (av. BMI 22) took part in a study to determine the impact of time on the affect of food recall. Two groups were created.1.Recall today’s lunch2.Recall journey to test centreParticipants carried out tests 1 hour or 3 hours after lunch. They were provided with astandard lunch then hunger, fullness, and desire to eat (HFD) were rated and participants returned 1 or 3 hours later. Participants wrote details of their lunch or journey then were then free to eat cookies. HFD was rated and cookie consumption calculated. Cookie intake was greater after 3 hours however food recall did not lower intake in high disinhibitionparticipants, however in low disinhibition participants intake was lowered and the effect was greater after 3 hours. Limitations of the study·Cannot demonstrate how this effect occurs.·All participants were of normal weight. ·All participants were relatively young.·The study only shows a short term effect·The effect was only significant in low disinhibitionparticipants

Daily express article analysisThe article gives a brief overview of the study only after making claims that do not fit with the research conclusions. It states recall can ‘prevent’ snacking; the study merely claims that it may reduce the amount consumed. It then claims the harder you think about the meal, the greater the effect, a parameter never even investigated by the researchers.

Daily Mail article analysisThis article gives a more comprehensive overview of the study’s procedures, results and conclusions. However, it fails to mention its limitations. It states recall reduces the desire to snack when in factappetite was not found to be affected by recall. The article does however describe other research expanding on and supporting the original study including the idea that memory function may affect the quantity consumed.

The article begins by stating that scientists have found “the cure” for snacking to be thinking about you last meal. People who think about their lunch before snacking ate less than those who thought about their journey. The effect grew with time up to three hours. Those with brain damage will eat many lunches but can be helped by being reminded of the food they have already eaten.

MethodIn this study we examined media coverage of two scientific studies. All of our primary literature was garnered from the NHS Choices website dealing with media coverage. The first article was a study investigating the effect of knowledge based tasks on calorific intake by Chapput et al. 2008. Using the NHS website, a media article from each the Daily Express and the Daily Telegraph that covered the original paper were investigated in their online format. The second article was a study investigating the effect of recalling lunch on afternoon snacking and other factors that could impact this effect. It was published by Higgs et al. in 2008. Two media articles covering the paper were found, again through the NHS Choices website. One from the Daily Mail and another from the Daily Express. The journal papers themselves were analysed and criticed. The newspaper articles were then compared to the original scientific papers and were analysed to see how accurately the facts and conclusions of the research were portrayed. The style of writing used in newspaper articles to portray scientific research was also analysed , particularly a technique often seen called inverse pyramid writing. Finally, the data from the SIRC and UK national health survey relating to obesity and media coverage rates were analysed to see the larger effect of obesity coverage and whether this coverage is proportional to the problem.

AbstractThe media is a large force within society and has become the primary source of scientific information for the general public. Despite this enormous responsibility there is little to ensure that their portrayals are accurate as few checks and balances exist and the media has a different bottom line than science and medicine. Four different media articles from 3 newspapers were investigated and found to have contradicting messages on the relationship of thinking to food intake. It was found that the media articles used inverse pyramid writing to capture the reader and portray the desired conclusion of the tabloid rather than the scientific journal. This is worrying since the media should not be used as a source of scientific information, which it invariably is in the case of much of the general population.

ConclusionObesity is a topic that is largely publicised in the media. Although obesity rates in adults may be increasing, government health data shows that child obesity rates are not on such a dramatic rise as the media suggest. The media articles investigated in this study deliver opposing messages, two of which, only five months apart in the same paper. After analysing the original scientific papers upon which the articles were based, with the use of pyramid writing, the respective media articles modified the content. Clear cut conclusions that thinking makes you both fatter and thinner were made, something not implied in the original papers. In conclusion, it is not viable to believe everything that is presented in the media and it should not be used as a source of scientific information. Instead all evidence should be reviewed and primary literature found. This causes concern, as the media is the main source of information for the general public, who therefore may be mislead in the information they rely on.

Arora S., Chahwan A., Francis R., Husseneux A., Kumar A., Moss S., Pickard A., Samiy S., Thompson G.,Department of Medicine, Barts and the London School of Medicine and Dentistry, London, UK.

Figure 5 Mean BMI of Adults and Children 1993-2006

DiscussionScientific journals are designed as a method of communication within the scientific community, no provision was ever made to pass this information on to the general public. Many complex scientific debates take years before they can be agreed upon by a majority, and the nature of science means that theories and information are constantly being refined. The media, mainly news agencies have become over time the means by which science is disseminated to the public, but the media has a different set of rules and a different bottom line than science. The media often attempts to show both sides of a debate sometimes giving equal weighting to an argument that within the scientific community is definitely not evenly divided. In this way the general public can receive mixed and confusing messages about issues, and can believe that science is divided on an issue when it in fact isn't. Within this study we examined media coverage of two scientific papers and looked overall at the media interpretation of the scientific outcomes, in all cases the media came to conclusions that were not supported by the scientific papers which they were based upon (Chaput et al. 2008) (Higgs et al. 2008). Furthermore government sponsored reviews have found that media coverage of obesity was not to always accurately representative of the true rate and prevalence of obesity within the UK. Particularly media representations of childhood obesity rates have been exaggerated and cannot be supported by UK national health data as they cannot be seen as rising any faster than proportional to the population (SIRC 2005) (National Health Survey 2006) (Figure 6).

Led by the increased media coverage the public are more and more wanting input into the scientific process and increasingly interested in this “bite-size” science; science that has been removed from the framework of the debate and the scientific discussion that it is part of. Medicine and science face increasing scrutiny from the public and media, and face the very real possibility of having to justify legitimate research lines, to people with little or no scientific background. Whether or not you agree with increasing public ownership and participation in the direction of science and medical research the increased powers given to the media in this respect are disstressing. The media has now become the main mechanism of disseminating science to the public, this is worrying as the media owes no allegiance to anyone but its investors and its primary goal is not to disseminate the truth but to sell its brand. This study has illustrated the perils of believing everything you read and has shown extreme caution should be used when we interact with the media as health professionals. Whenever possible we should rely on primary literature and actively contribute to public education about the issues they read about. Furthermore a need for a more responsible mechanism of disseminating and debating scientific and medical advances within the media is needed.

IntroductionThe past 10 years have seen obesity within the UK rise to become a major public health concern, legislation, funding and research have all been directed at this growing problem. Media coverage of obesity rates has without any doubt been a major driving force behind this. The media has come to have many different roles within the framework of public education on health issues, it not only reports on scientific discoveries but can in many ways direct them by covering the stories it likes. The scientific community has no control on the types of articles that are written and the coverage of issues by the general media, and very few checks and balances are in place to ensure accuracy of information. This study investigates media coverage of two rather esoteric scientific articles both related to cognitive processes and weight gain. This study also examines recent government health surveys for actual prevalence of obesity to identify if the media accurately portrays obesity rates in the UK. Within media interpretations of both scientific papers the conclusions of the scientific paper are not represented truthfully, leading a reader to believe the scientific papers to be far more certain than they were.

Figure 4 Test condition results Mean +/- SDFigure 6 Global trends in Media Coverage of Obesity

Daily Express article analysisThe media articles state thinking makes you crave food but increased food intake does not imply a craving of food. The titles of the articles are misleading especially “think big…and get fat” as this implies a relationship which the original study did not conclude. Information taken from the study was used to make generalisations about the general public that were not implied in the study. Although the study comes to no real conclusion on the issue, the media articles put more importance on the issues raised and imply they should be a concern for the public.

Figure 1 Global Obesity Map

Figure 2 BMI Chart

This article explained that subjects partook in the following tasks: relaxing in a sitting position, reading and summarising, memory attention and vigilance tests on a computer for 45 minutes each. They explained that different tasks caused fluctuations in glucose and insulin levels which resulted in an increase in food intake of 23.6 and 29.4% to restore balance, which they assert could be a contributing factor to the obesity epidemic.

Figure 3 Test Conditions

The article states that remembering your last meal can suppress appetite and that people can teach themselves to resist snacking. An overview of the experiment and its results is given followed by a description of a study in which women who were distracted by television ate more than those who focused on their food. The hippocampus is the part of the brain involved in recalling food and may be manipulated to treat obesity in the future.

References

Chaput J., Drapeau V., Poirier P., Teasdale N., Tremblay A. 2008 Glycemic Instability and Spontaneous Energy Intake: association With Knowledge-Based Work. Psychosomatic Medicine 70;797-804

Global Trends in Media Coverage of Obesity 2008 last viewed November 10th 2008<http://www.nursingcenter.com/library/JournalArticle.asp?Article_ID=539952>

Health Survey for England 2006 National Statistics UK 2008 last viewed November 30th 2008< http://www.ic.nhs.uk/pubs/hse06trends>

Health Survey Raw Data for Adults and Children 2006 National Statistics Uk 2008 last viewed November 30th 2008< http://www.ic.nhs.uk/pubs/hse06trends>

Higgs S., Williamson A.C., Attwood A.S. 2008 Recall of lunch and its effect on subsequent snack intake Physiology and Behavior 94;454-462

Image of World Health Organization Map of World Prevalence of Obesity 2005, BBC News UK 2008 last viewed 10th

December 2008< http://news.bbc.co.uk/1/hi/health/7151813.stm>

Image of BMI Chart 2006 BBC News UK 2008 last viewed 1st December 2008<http://news.bbc.co.uk/nolpda/ukfs_news/hi/newsid_5297000/5297790.stm>

S i l I R h C t R i f N ti l H lth S l t i d D b 10th 2008

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