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by Dr. Damayanthi Perera , Ph D - Human Nutrition (London) Nutrition Consultant/Independent Researcher.

The scientific data presented in this article indicate that heart disease, hypertension (high blood pressure), and diseases such as diabetes that predispose an individual to heart disease and stroke are common problems amongst both the rich and the poor of this country today. The important question is that in a back drop such as this, how could heart patients or even healthy people be 'recommended' to consume foods such as fried salted cashew nuts (high in salt and energy) and also other energy dense foods such as nuts or avocado adlibitum (without restrictions).

There are different principle of Nutrition and Diet Counseling. When dietary advice is offered at 'individual level' it is crucial to adopt a 'Holistic Approach'. When advice is offered on mass media at 'national level' it is also important to consider the existing health and nutrition situation of the country ie: the Nutrition Transition that is taking place in Sri Lanka at present.

This article highlights a classic example of a mismatch between the health and nutrition situation of the country and the nutrition and dietary advice offered to the public via the mass media. The above misinformation has created a need to educate the public on the scientific position with regard to the consumption of energy dense foods. This article raises important questions in relation to public health, professional obligations/ethics and media ethics.

Background: I write with reference to Mr. R. Wickremasinghe's letter to Dr. D. P. Atukorale (Daily News, Health Watch, 15/11/02) titled Kadju and Cholesterol and Dr. D. P. Atukorales's reply to Mr. Wickramasinghe titled Controversy about Cashew Nuts and Avocado (Daily News, Health Watch, 29/11/02). In his letter Mr. Wicremasinghe (whom I shall refer to as Mr. Wic) states that he is a heart patient who is attending the Cardiology Unit of the General Hospital regularly and when he inquired about the above matter, the doctors from the unit vehemently objected to his consuming cashew nuts, avocado and coconut oil.

Mr. Wic queries from Dr. Atukorale, as to the basis on which Dr. Atukorale recommends heart patients could eat cashew and avocado without any 'reservations' as against the advice of many other doctors. Mr. Wic also had the following to say "It is time that the Medical Council meet and have a discussion on this subject and arrive at a final decision in order to put the mind of the public at rest once and for all, as this controversy has dragged for too long" Interestingly, Mr. Wic also noted that "Something is wrong somewhere".

I trust the above quotes highlight the dilemma of the public, particularly, people like Mr. Wic who are affected by heart diseases and need to be given sound dietary advice. Doctors at the Cardiology Unit have used a cautious approach which is also a very wise approach. It is best to err on the side of caution. Indeed, as very rightfully stated by Mr. Wic, something is very wrong somewhere and I shall try to explain to the readers what is wrong. I request the readers also to refer my reply in the Daily News, Health Watch of 13/12/02, Cashew, avocado and heart patients: a reply.

Points to ponder: However before I go into the scientific details I wish to place some important questions before the public. As explained below, currently the Sri Lankan public is highly confused with regard to many important nutrition related issues that have a major bearing on public health. If you or one of your loved ones are suffering from heart disease or you come from a family with a history of heart disease which puts you at risk of developing the disease what kind of nutrition information and dietary advice would you like to hear on the media? Sensational, selling news or sound, scientific information? Please read the following information carefully and decide for your self.

A matter of National Importance: The above issue with regard to incorrect nutrition information and dietary advice appearing on the print media frequently is a matter of national importance since it has important public health implications and should not be swept under the carpet. I believe in standing up for the rights of the people through my profession, especially defending the rights of the average and the underprivileged citizens of this country.

A Nutritionist's primary obligation is to safeguard the Health and Nutrition status of the general public of this country. If I do not highlight these problems at this stage, I will be failing in my responsibility to safeguard public health as a professional as well as a responsible citizen of this country. It will be easy to silence a single individual struggling for a cause but I believe the medical community who bear a greater obligation, will live up to it's reputation and the expected standards and view this problem from purely scientific angles.

In this regard, I have in mind, the Sri Lanka Medical Council, Sri Lanka Medical Association, Heart Association of Sri Lanka and other medical associations and the medical fraternity of this country.

Dilemma of the public: First and foremost I wish to state as to why I am entering in to this controversy. Mass Media can be used for promoting both positive (ie: health education) and negative (the above is one example and also commercial advertising of food products luring the public to eat the wrong kinds of food is another) health messages. In a country like Sri Lanka, nutrition education can play a very positive role in the prevention of diet related Non Communicable Diseases (NCDs)/ diet related chronic degenerative diseases.

This was highlighted by this author in an article titled Preventing non-communicable diseases through nutrition education, Daily News, 17th May 2002. My discipline compels me to provide an up-to-date and timely nutrition information to the Sri Lankan public and therefore I have engaged in educating the general public on important nutrition related issues such as obesity, diabetes, heart disease etc. through print and electronic media and also through other forums.

Urban: Chronic diseases/conditions such as overweight, obesity, diabetes, hypertension and heart disease etc are common problems in Sri Lanka and are on the increase.

The above assessment is substantiated by scientific research data cited below. In Sri Lanka the urban affluent have already acquired a modern, western type of diet and a life style with a concomitant increase in diet related non communicable diseases (NCDs). Currently, diet related chronic degenerative diseases such as obesity (Fernando and Siribaddana, 1994), diabetes (Fernnando et al., 1992), cardiovascular disease (heart disease, stroke; Mendis, 1998) are notable problems in Sri Lanka. In a study conducted in suburban (Maharagama) Sri Lanka, it was found that the study participants had a higher prevalence of dyslipidaemias (fats in the blood such as cholesterol, triglycerides), diabetes, obesity, hypertension and central obesity (fatness around the stomach which is a risk factor diseases such as diabetes, heart disease etc) compared to European subjects but lower than those reported in migrant South Asian populations (Fernando and Siribaddana, 1994). Research repeated in the same community after a decade indicated an increase in the prevalence of diabetes and vascular risk factors.

According to the authors, the prevalence in younger age groups indicate that ischaemic heart disease will become more common. It has been pointed out that the epidemic of diabetes has already commenced in Sri Lanka and diabetic patients over 65 have been shown to consume a disproportionately large amount of health care resources. It is known that diabetic persons are more prone to heart disease and stroke than non-diabetic people.

It is of concern to note that suburban Sri Lankans developed diabetes at a younger age and at a lower Body Mass Index compared to a similar group of diabetics in Manchester, UK. It is also important to highlight that at diagnosis, the Sri Lankan diabetics have a higher prevalence of complications such as coronary vascular disease, hypertension, stroke, neuropathy and retinopathy compared to Caucasian (white) and Indo-Asian patients in the UK (Weerasuriya et al, 1998). In a number of these articles the authors highlight the importance of a healthy diet and lifestyle and the need for prevention.

There is also anecdotal evidence that diet related cancers such as breast and prostrate cancer etc is on the increase in Sri Lanka. Overweight/obesity is a common risk factor for most of the diet related chronic diseases and the amount and the type of fat intake of a population too have a direct or indirect relationship with most NCDs.

Rural: Contrary to the popular belief that diet related chronic diseases/ NCDs are diseases of the affluent, such diseases are on the increase in the rural areas too. Based on the scientific research information (Barker and Osmond, 1896; Barker, Osmond and Law, 1989; Barker, 1992; Barker, 1995; Moor and Davis, 2001) it was argued by this author that with improved economic status, poor of this country too will be affected by such diseases in the near future, unless timely, preventive action is set in motion (Damayanthi Perera, Nutrition in transition: Towards a National nutrition Policy for addressing the 'existing' and 'emerging' nutrition challenges of the 21st century, Biennial Scientific sessions of the Nutrition Society, 16th March 2002.

A news article published soon after confirmed the author's views. According to Dr. K. Rajakanthan, Consultant Cardiologist, Teaching Hospital, Kurunegala (cited by Naomi Gunasekera, Sunday Times, 31/03/02), with urbanization and industrialization of the rural areas, heart disease has become the No. 1 killer in the North Western Province (NWP) and 40% of the deaths are due to heart ailments. NWP is the second largest province in Sri Lanka with an approximate population of 2.2 million.

According to the statistics provided, NWP has over 42,000 patients suffering from coronary heart disease in the Kurunegala District while 350,000 suffer from hypertension. The article highlighted the lack of facilities to treat cardiovascular patients and the plight of the rural NCD patients (see: Kurunegala's heart crusade, Gunasekera, loc.cit).

The above have significant implications for public health and the data highlight the urgent need for prevention of NCDs through appropriate dietary and other lifestyle interventions. Considering the above, I trust that the policy makers, the media, the medical fraternity and the lay community would agree that providing unhealthy dietary advice on mass media is a serious matter and it is time to arrive at some serious policy decisions in the interest of public health.

Nutrition Intervention Trial (experiments in which study foods are fed to study subjects under certain controlled conditions) data are particularly difficult to interpret due to various nutrient interactions that take place within the body at metabolic level and also due to difficulties in controlling various confounding factors (health, dietary and socio-cultural factors) that may affect the results. Nutrition Epidemiological Observations (where the scientists observe dietary and other lifestyle factors of large free-living populations) provide associations between social, health and nutrition variables.

Associations do not prove cause and effect. Therefore, interpretation of nutrition data, particularly translating information from nutrition trials and epidemiological data into dietary advice must be done with utmost caution.

Cashew, and heart patients: On many occasions incorrect dietary advice has been given with regard to cashew consumption. In reply to Mr. Wic Dr. Atukorale states the following "It is common knowledge among doctors that in view of the high content of heart healthy mono-unsaturated fats and polyunsaturated fats which increase your serum HDL cholesterol and decrease your serum LDL cholesterol, all heart patients suffering from hyperlipidaemia should consume avocado and nuts such as cashew nuts, peanuts, hazel nuts, Brazil nuts and walnuts whenever it is possible as these contain very high quantities of monounsaturaated fats and polyunsaturated fats" (Daily News, Health Watch, 29/11/02).

Similarly, in another article it was stated that heart patients with high LDL and low HDL cholesterol are 'recommended' to eat cashew nuts in any form even fried, salted nuts! (Daily News, Health watch, 24/05/02). A few heart patients may be delighted to hear such advice, but this is not sound dietary advice.

In another article (Daily News, 16/04/01) it is stated that cashew is a highly nutritious food. Generalizations such as cashew is a 'highly nutritious food' is misleading because what is good for one person or a particular condition may be not be appropriate for another person.

Source and interpretation of scientific data: Along with Mr Wic's letter (Daily News, Health Watch, 15/11/02) Dr. Atukorale has made a note requesting the reader to refer Page 17 of the Readers Digest of November 2002. Although scientific advice is never based on articles from the popular press, I did refer the said article (which is approximately a 2X4" column slightly longer than the average obituary notice). The article referred to the Physician's Health Study in the USA that has examined the diet, health and exercise habits of physicians.

There are similar studies such as the Nurses Health Study, which has identified important associations between diet, lifestyle and health. One of the earliest studies that demonstrated an 'association' between nut consumption and lower rates of heart disease is the 7th Day Adventists Study of Fraser et al (1992).

All the above studies are epidemiological studies (observational studies carried out on free living individuals in the community) and it is important to bear in mind that an 'association' does not prove 'cause and effect'. Therefore, the problems of confounding that needs to be taken in to account with regard to the study of Fraser et al (loc. cit.) was very clearly highlighted in the Editorial Section of the same journal in which the Adventist's Study was published (William Castellie, Medical Director, Framingham Heart Study, 1992). Some interesting scientific information regarding the above study will be published on a latter date.

Additionally, all the above studies have been carried out in Western countries and it is important to note that in such countries people who include nuts 'regularly' in their diet are usually people who eat a Predominantly Plant Based Diet - PPBD. It is important to highlight that although a PPBD western diet is usually referred to as a vegetarian diet in the scientific literature for convenience, that there are major differences between the traditional Indian vegetarian diet and a PPBD diet that is consumed in western countries.

Usually such people exercise regularly, drink alcohol in moderation or abstain from it and maintain a healthy body weight. All the above are important confounding factors when assessing the relationships between diet, health and lifestyle. The very fact that these studies have been conducted in selected groups of people (ie: the Adventists, Physicians and Nurses) by it self is an important confounding factor.

There can be many such epidemiological studies and even Intervention Trials but none will change the Fundamental Principles of Nutrition and Diet Counseling and the fact that nuts and avocado are high calorie foods, and if consumed in excess will lead to overweight/obesity. Therefore, nowhere in the medical literature it would be stated that nuts or avocado could be added to a habitual diet without any limits or conditions as recommended by Dr. Atukorale. If avocado, nuts, olive oil or any such energy dense foods are included in the diet they should replace some of the other foods containing saturated fats, excess polyunsaturated oils and products, other energy dense foods or drinks.

Vegetarian Guide: In his subsequent reply to Mr. Wic (Daily News, Health Watch, 29/11/02) Dr. Atukorale justified his arguments further by stating that he is quoting from The Guide to Vegetarian Living by Peter Cox, Bloomsbury, 1994 which is an encyclopedia of vegetarian living which he considers as the ultimate authoritative guide. On a previous occasion too Dr. Atukorale had contributed an article titled Nutritional Value of Rice with reference to the same author (Peter Cox) and also a Mrs. Grieves (Daily News 28/02/02). This article on rice too contained many errors and generalizations, some of which were highlighted by C. Breckenridge (see The Island 03/04/02).

This is where that something has gone wrong. Health Books, Magazines and Health and Nutrition articles on print and electronic media (ie: internet) written by non-professionals in nutrition contain many misinterpretations. The above article on rice is a clear example. In addition to what was highlighted by Breckenridge, there were many other incorrect statements and broad generalizations on rice in the above article. It is not customary for the scientific community to offer public advice based on what is published in Readers Digest and publications such as the above vegetarian guide.

Health and socio-cultural practices: In nutrition and dietetic practice, such unconditional, generalized dietary advice is never offered to heart patients or healthy individuals, without taking other dietary and health (other illnesses), nutritional factors (ie: weight status) and socio-cultural practices in to consideration.

Contrary to the traditional belief that fat is more satiating than carbohydrates or protein it is now known that fatty foods are the least satiating out of the above (Holt et al, 1995). It is known how easy it is to passively over consume fatty foods such as nuts or Croissants (a light bread roll containing a high amount of fat). In Sri Lanka usually cashew is eaten deep-fried with other high-energy snacks, food and alcohol.

Therefore when dietary advice is offered one has to take such socio-cultural practices also in to consideration. As mentioned above, obesity and it's co-morbidities such as diabetes, heart disease, hypertension and diet related cancers are on the increase in Sri Lanka and when dietary advice is offered on mass media one needs to take the Health and Nutrition situation of the country in to consideration.

High fat/energy diet and Lack of exercise: Total and saturated fat and energy content of the Sri Lankan diet has increased over time. The traditional plate of rice is now laden with chicken, high fat meat products such as bacon, sausages, meat balls etc, accompanied by various types of Fizzy Drinks or alcoholic beverages depending on the age and social class. Such products are freely available even in rural areas. There is also anecdotal evidence to indicate that Sri Lanka has the highest per capita alcohol consumption in the world! In addition to the above, margarine and full fat milk products that are high in fats and energy are used on a regular basis by the people who could afford such foods.

Most adults and children engage in little or no leisure time physical activity. Electronic revolution (ie:computers and internet) is a major factor contributing to reduced recreational physical activity. For many urban Sri Lankans, both young and not so young, Net Surfing (spending much time on the internet which is a sedentary activity) probably is the only form of leisure time activity! Ironically, these are the people who subscribe to the English Dailies of Sri Lanka and recommending such people to eat energy dense foods such as cashew and avocado ad libitum (without restrictions) is highly questionable.

However, it is important to note that it is not only the urban affluent that has lower energy expenditure. The lifestyle and the energy expenditure pattern of the majority of the rural folk too have changed and they too engage in much less physical activity than they were traditionally accustomed to. It is also important to remember that the people of the lower social classes like to imitate the lifestyles of the urban affluent.

Unfortunately, at a time when urban school kids are taking hamburgers and pastries (high fat snacks) in their lunch boxes and Colas as their drink, the LD recommends that "Cashew nuts are a particularly good snack for lunch boxes and for growing children ..." (Daily News, Health Watch, 29/11/02). It is clear that the LD is not aware as to what goes in the lunch boxes of both adults and the children who are vulnerable to NCDs. It is important to remember that children who can afford to take Cashew nuts in their lunch boxes are also likely to be consuming other foods high in fat/ energy foods such as pastries, ice creams, crisps, fizzy drinks etc during the school interval and also at home.

An invitation to obesity: In brief, at a time when Sri Lanka needs to seriously think about sound nutrition advice to prevent overweight/obesity, and its related co-morbidities (illnesses) such as diabetes, cardiovascular disease, hypertension etc this is an open invitation to obesity! Above arguments are fundamentally incorrect and are in total violation of Basic Principles of Nutrition and Dietetics and Diet Counseling. There is no dispute that foods such as cashew and avocado contain Mono Unsaturated Fatty acids (MUFA) considered as heart healthy. However, such foods are never recommended without conditions or limits.

A nutritionist/dietitian may incorporate foods such as cashew or avocado in limited quantities, after making an assessment of the health and nutrition condition of the patient and dietary intake data. However, just because a food is known to contain MUFA such foods are never 'recommended' with out conditions or ad libitum (without limits). A good example is olive oil. Olive oil contains the highest proportion of MUFA (average 75%) but any food that is high in calories such as avocado, nuts and olive oil are never recommended without limits. If avocado, nuts, olive oil or any such energy dense foods are included even in the diet of healthy people they should replace some of the other foods containing saturated fats, excess polyunsaturated oils and products, other energy dense foods or drinks.

Available scientific data indicate that health and nutrition situation of Sri Lanka is in transition, and as has happened in this instance there can be a mismatch between the nutrition information and dietary advice offered to the public and the health and nutrition situation of the country. There are important policy implications arising from this issue. The brighter side is that there are lessons to be learnt from this experience and it is possible to avoid such mistakes in the future.

Avocado and heart patients: I do not wish to spend much time on the issue of avocado, because the arguments behind avocado too are the same. It is of concern to note articles appearing with captions such as 'Avocado a solution for heart disease', D P Atukorale (Daily News, Health Watch, 30/05/01). Heart disease has a 'Multi Factorial Aetiology' and prevention and treatment of heart disease requires a 'Multi Pronged Approach'. Asking people to eat avocado adlibitum is not a solution to heart disease. It is also important to note that there are differences between a diet prescribed for preventing heart disease as opposed to a diet that is prescribed to patients with existing heart disease.

In the interest of public health, could the LD kindly substantiate these 'recommendations' by producing any 'scientific' references (not advice from health books or magazines, internet, Readers Digest etc) which state that heart patients are 'recommended' to eat cashew nuts or avocado without any conditions? It is up to the to the public and the medical community to decide whether it is scientific or ethical to provide such flawed dietary advice to the public on mass media or otherwise. The following section highlights the ethical issues and the need to introduce media ethics for scientific writers.

Responsible scientific reporting and media ethics: Mass media exerts a powerful effect on the public, be it politics, fashion or food & nutrition. Therefore, incorrect nutrition information and unsound dietary advice offered on mass media may contribute significantly to an increase in diet related non-communicable diseases (NCDs)/chronic degenerative diseases such as overweight, obesity and its co-morbidities (related diseases) such as diabetes, heart disease, hypertension (high blood pressure), diet related cancer etc. An increase in NCDs will affect the health and wellbeing of the public and will also lead to increased health expenditure at personal and national level.

This is a free country with freedom of speech and any one is free to contribute to the media keeping in line with the accepted media regulations and ethics. However, when it comes to information relating to 'applied sciences' that may have a direct or indirect bearing on public health, contributed by professionals, there is a collective obligation by the writer, publisher and the policy maker to ensure that what is published using the free media will not jeopardize public health. Key issues and Conclusions: Nuts or MUFA are not the issue here.

The key issue is the unscientific and irresponsible manner in which scientific information has been disseminated to a large group of people who are vulnerable to obesity and its related co-morbidities (illnesses) such as diabetes heart disease, hypertension etc via the mass media. This article demonstrates clearly the dangers of using the mass media by people who are not trained in nutrition to deliver nutrition messages to the public and the confusions that can arise as a result of conflicting and incorrect messages given to the public through mass media. Implications of such advice may not be obvious immediately but it will take its own toll eventually.

Therefore, this article raises public health, and ethical issues in relation to persons not qualified in nutrition providing nutrition and dietary advice to the public on mass media or otherwise.

Available scientific data indicate that health and nutrition situation of Sri Lanka is in transition, and as has happened in this instance there can be a mismatch between the nutrition information and dietary advice offered to the public and the health and nutrition situation of the country. There are important policy implications arising from this issue. The brighter side is that there are lessons to be learnt from this experience and it is possible to avoid such mistakes in the future.

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