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Background: Coronary heart disease (CHD) was an important epidemic in many developed countries in the 20th century and there is concern because the epidemic has affected Eastern Europe, Russia and Central Asia and is starting to affect developing countries. Methods: The epidemic curves of CHD mortality for 55 countries, which had reliable data and met other selection criteria, were examined using age-standardised death rates 35–74 years from the World Health Organization. Annual male mortality rates for individual countries from 1950 to 2003 were plotted and a table and a graph used to classify countries by magnitude, pattern and timing of its CHD epidemic. Results: The natural history of CHD epidemics varies markedly among countries. Different CHD patterns are distinguishable including “rise and fall” (classic epidemic pattern), “rising” (first part of epidemic) and “flat” (no epidemic yet). Furthermore, epidemic peaks were higher in Anglo-Celtic countries first affected by the epidemic, and subsequent peaks were less, except for the recent extraordinary epidemics in Russia and Central Asian republics. There were considerable differences among some continental or regional geographical areas. Eastern European, South American and Asian countries have quite different epidemic characteristics, including shorter epidemic cycles. Conclusions: It cannot be assumed that WHO regions or any other geographical regions will be useful when analysing CHD epidemics or deciding upon strategic policies to reduce CHD in individual countries. The needs for action that are urgent in some countries are less so in others, and even regional country groups can have quite different epidemic characteristics.

The sum of evidence-based nutrition has to be more than a Cochrane-type meta-analysis of randomised controlled trials (RCTs). Most of the evidence base in nutrition is observational, especially cohort studies. RCTs of diet change through to disease outcome are uncommon and the change has usually been addition or removal of only a single food component. Trials with whole diets through to disease outcome are rare and dietary changes made by individuals are unlikely to be an exact copy of the prescription. It is hard to even imagine a trial in which half (randomised) of a large group of middle-aged people agree to avoid vegetables for 5 y and be followed up to see who will develop cancer. Most of the USA's health claims, permitted by the Food and Drug Administration, are not supported by RCTs. But where controlled trials of nutritional change and disease outcome have been achieved, they must be reviewed very carefully. Two Cochrane reviews on diet and cardiovascular disease (CVD), published in the widely read British Medical Journal (BMJ), were criticised after their publication and the conclusions have not been subsequently adopted by expert committees. The first of these reviews was 'Dietary fat and prevention of CVD: a systematic review'. The second was 'Systematic review of long term effects of advice to reduce dietary salt in adults'. A critique of these two Cochrane reviews is presented here as a contribution to our discussion of the potential of Cochrane methodology to the reliability of knowledge about diet and disease.

This review outlines a hypothesis that A1 one of the common variants of beta-casein, a major protein in cows milk could facilitate the immunological processes that lead to type I diabetes (DM-I). It was subsequently suggested that A1 beta-casein may also be a risk factor for coronary heart disease (CHD), based on between-country correlations of CHD mortality with estimated national consumption of A1 beta-casein in a selected number of developed countries. A company, A2 Corporation was set up in New Zealand in the late 1990s to test cows and market milk in several countries with only the A2 variant of beta-casein, which appeared not to have the disadvantages of A1 beta-casein. The second part of this review is a critique of the A1/A2 hypothesis. For both DM-I and CHD, the between-country correlation method is shown to be unreliable and negated by recalculation with more countries and by prospective studies in individuals. The animal experiments with diabetes-prone rodents that supported the hypothesis about diabetes were not confirmed by larger, better standardised multicentre experiments. The single animal experiment supporting an A1 beta-casein and CHD link was small, short, in an unsuitable animal model and had other design weaknesses. The A1/A2 milk hypothesis was ingenious. If the scientific evidence had worked out it would have required huge adjustments in the world's dairy industries. This review concludes, however, that there is no convincing or even probable evidence that the A1 beta-casein of cow milk has any adverse effect in humans. This review has been independent of examination of evidence related to A1 and A2 milk by the Australian and New Zealand food standard and food safety authorities, which have not published the evidence they have examined and the analysis of it. They stated in 2003 that no relationship has been established between A1 or A2 milk and diabetes, CHD or other diseases.

Since the major reviews on diet and cancer by the World Cancer Research Fund (WCRF) and by the British Department of Health's Committee on Medical Aspects of Food Policy (COMA) in 1997 and 1998, additional epidemiological studies relating (red) meat consumption and colorectal cancer have been published or found by search. These are collected here. Thirty adequate case–control studies have been published up to 1999 (from 16 different countries). Twenty of them found no significant association of (red) meat with colorectal cancer. Of the remaining 10 studies reporting an association, some obtained statistical significance only in rectal or colon cancers, another only in men, not women, or found a stronger association with pasta and rice, or used an inadequate food list in the food frequency questionnaire. Fifteen cohort studies have now been published. Only in three were significant associations of (red) meat found with colorectal cancer. Two of these positive studies were from the same group in the USA (relative risk 1.7). The results of the third positive study appear to conflict with data from part of the vegetarians follow up mortality study. Here, five groups of vegetarians (in three different countries) with socially matched controls were followed up (total 76 000 people). Mortality from colorectal cancer was not distinguishable between vegetarians and controls. While it is still possible that certain processed meats or sausages (with a variety of added ingredients) or meats cooked at very high temperature carry some risk, the relationship between meats in general and colorectal cancer now looks weaker than the ‘probable’ status it was judged to have by the WCRF in 1997.

Interest in Mediterranean diet began 30 years ago, when Ancel Keys published the results of the famous Seven Countries Study, Since 1945, almost 1.3 million people have come to Australia from Mediterranean countries as new settlers. There are 18 countries with coasts on the Mediterranean sea: Spain, southern France, Italy, Malta, Croatia, Bosnia, Albania, Greece, Cyprus, Turkey, Syria, Lebanon, Egypt, Libya, Malta, Tunisia, Algeria and Morocco. This study from which this report derives aims to investigate the influence of the food habits of immigrants from Mediterranean countries on Australian food intake. Here we look at the 'traditional' food habits of the above Mediterranean countries as told by 102 people we interviewed in Sydney, who came from 18 Mediterranean countries to Sydney. Most of the informants were women, their age ranged from 35 to 55 years. The interview was open-ended and held in the informant's home. It usually lasted around 1 1/2 hours. The interview had three parts. Personal information was obtained, questions relating to the food habits of these people back in their original Mediterranean countries and how their food intake and habits have changed in Australia were also asked. From the interviews, we have obtained a broad picture of 'traditional' food habits in different Mediterranean countries. The interview data was checked with books of recipes for the different countries. While there were similarities between the countries, there are also important differences in the food habits of the Mediterranean countries. Neighbouring countries' food habits are closer than those on opposite sides of the Mediterranean Sea. We suggest that these food habits can be put into four groups. The data here refer to food habits in Mediterranean countries 20 or 30 years ago, as they were recovering from the Second World War. There is no single ideal Mediterranean diet. Nutritionists who use the concept should qualify the individual country and the time in history of their model Mediterranean diet.

This article summarizes presentations from an international workshop held in Heelsum, Netherlands, 14-16 December 1998 that was sponsored by the Dutch Dairy Foundation on Nutrition and Health, the Department of Nutrition at Wageningen Agricultural University, the Dutch College of General Practitioners, and the International Union of Nutritional Sciences. Twenty-one speakers and 12 other participants were invited from 9 countries: the Netherlands, the United States, the United Kingdom, Australia, Canada, Denmark, New Zealand, Spain, and Sweden. The workshop was chaired by GJAJ Hautvast and the scientific secretary was GJ Hiddink. Family physicians are highly trusted. Many consultations include a nutritional aspect, but physicians do not discuss nutrition with their patients as often as they could. Major barriers include short visit times, the paucity of nutrition teaching in medical schools, and poor compliance of patients with physicians' dietary prescriptions. Problems, practicalities, operational research, and some solutions were discussed at this meeting of leading family doctors with interested nutritionists. Family physicians have to distill the essentials for their patients from many different specialties ranging from ophthalmology to podiatry. They look for clarity of recommendations from nutrition researchers. Among developments discussed at the meeting that can increase nutritional work in family medicine are 1) new opportunities to teach nutrition in vocational training programs, 2) some manuals and a new journal specially written by nutritional scientists for family physicians, 3) nutritional advice being incorporated into computer software for family physicians, 4) more dietitians working with family physicians, and 5) nutrition training for practice nurses in some countries.

The last Heelsum workshop agreed that general practitioners should concentrate on dietary advice for treatment or secondary prevention, though nutritional advice for health is part of the doctor’s work with pregnancy, infants and the very old. Nutrition prescriptions contrast with drug prescriptions. For drugs information is authoritative, evidence-based and easily available. Drug prescriptions are potentially liable to litigation. Dietary prescriptions are less serious and more the patient’s responsibility. Nutrition information comes in a plethora of different forms, some of it unscientific, some out of date, some commercially biased. While waiting for some system (?authoritative, ?electronic) that can help general practitioners (GPs) organise nutrition information, there are three modern books that have been written by nutrition specialists for GPs in the English language (there may be others in North America) and another was written for practice nurses. As well as general books like this most large countries have expert reports on some nutritional topics by government committees available for reference. In relating foods and food components to disease, most of the reliable evidence is about their effect on risk factors — plasma cholesterol, blood glucose, blood pressure or body weight. A smaller amount of evidence relates food intake data from large cohort studies to incidence of disease. Very few randomised controlled trials (the ultimate evidence-based medicine) have been achieved for nutrition. Dietary recommendations may have to change with time because of new research — and drugs. Advice for secondary prevention of coronary heart disease is shown as an example of this.

Evidence assembled here indicates that when olive oil forms a major part of dietary fat in controlled human experiments, total and LDL-cholesterols are somewhat higher than when the same amount of fat is one of the modern predominantly monounsaturated oils: low erucic rapeseed or high oleic sunflower oil. Oils rich in monounsaturated fatty acids thus do not all have the same effect on plasma cholesterol. This phenomenon is explicable by consideration of the content of other fatty acids and the non-saponifiable fractions of the different monounsaturated oils. It helps to explain the discrepancy that has existed between the classic experiments (using olive oil), which found monounsaturated oils 'neutral', and some of the more recent experiments which found them more cholesterol-lowering than carbohydrates. Four published meta-analyses are reviewed. The three which included most of the published experiments show that monounsaturated fatty acids (MUFA) have less plasma cholesterol-lowering effect than polyunsaturated fatty acids.

Nutrition research cannot improve people's health until the results influence their purchases and consumption of food and drink. There is much noise in the food information system. The most efficient solution to the problem of insufficient or conflicting public information is for all the data to be critically evaluated by a well-balanced expert committee convened by an authoritative body to produce dietary guidelines for wide publication. Such guidelines in different countries have many similar elements. Guidelines cannot be revised every year, but should be adapted only in response to major new research findings rather than to reports about nutrition in the media, which are no more than trivial distractions. The problems of family physicians giving one-on-one nutritional advice are discussed. For public health nutrition work, dietary guidelines have a range of products such as food guides and health claims on foods that are the tools of nutrition education. In developed countries, consumption of some foods has changed along with the guidelines; consumption of other foods has not. Coronary artery disease mortality has declined but obesity has increased. A more food-based approach to nutrition education is to use ideal diets as the model, such as the traditional Mediterranean diet, Japanese diet, or "hunter-gatherer" diets. These ideal diets would then need to be adapted to our present food preparation technology.

Cataract (opacity of the lens) and age-related degeneration of the macula of the retina are very common causes of disability in old age, and people are living longer. It seems likely that both of these conditions result from gradual photo-oxidative damage. The proteins in cataractous lenses are oxidized and 50 per cent of the fatty acids in membranes of retinal photo-receptors are highly polyunsaturated. The eye normally has unusually high concentrations of vitamin C and zinc which could have protective functions against free radical damage. For cataracts five reported case-control studies are reviewed and two prospective studies one of which included a very large number of subjects. Vitamin intakes were estimated from dietary histories or blood levels. In five of the six studies in which vitamin C was measured it appeared to be protective and vitamin E and carotenoids appeared protective in 5/7 studies. Other descriptive epidemiological studies are going on, including one in the Blue Mountains near Sydney. It is concluded that controlled trials of antioxidant nutrients for cataract prevention are now warranted. As to age-related muscular degeneration (ARMD), severe vitamin E deficiency is known to cause (a different type of) retinal degeneration spontaneously in humans (with cystic fibrosis or abetalipoproteinaemia) and experimentally in animals. Only three human case-control studies of ARMD and diet have been reported thus far and no clear relationship with any particular nutrient has emerged yet. Supplements containing antioxidant vitamins and zinc are being advertised and used in the USA and elsewhere but this is ahead of the evidence. More observational studies are needed and the US National Eye Institute is planning a 10 year intervention study, known as AREDS (Age-Related Eye Disease Study).

Health authorities are advising people to increase folate intake and more foods are being fortified with folic acid. Estimation of dietary folate is difficult because nutrient data bases lack this nutrient in many countries and bioavailability is variable. To see if serum folate can be used to reflect effective folate intake, we have measured serum folate after healthy women had taken different doses of pure folic acid supplements in the nutritional range.A total of 20 volunteer subjects took part in one or more of three experiments, six of them took part in all three. In each experiment subjects took two different doses of folic acid, each for three weeks. Experiment (1) 100 micrograms then 1000 micrograms/d; experiment (2) 500 micrograms then 1500 micrograms/d; experiment (3) 1000 then 2000 micrograms/d. Serum folate was measured after overnight fast with a homogenous enzyme binding assay kit. In experiment (3) red cell folates were also measured.It took three weeks' of the same supplement for serum folate to reach its full higher value. Mean serum folates of small groups of subjects were significantly higher with each higher dose of supplement. The biggest increase was for the first 100 micrograms that is in the range of intake from unfortified foods. The curve of serum folate against folic acid supplement intake shows that serum folate of groups of people, properly standardized, can provide a practical method for assessing adequacy or change of people's folate intake. Red cell folates were less responsive.

Australia has had an official guideline for the last ten years, that people should aim to consume less than 100 mmol sodium per day (equivalent to 6.0 g NaCl). The only practical way of estimating sodium intake is from the 24-h urinary sodium excretion. Between 1970 and 1980 average sodium excretions in different Australian surveys ranged from 130 to 200 mmol/day (middle number 165 mmol/d). These surveys involved small numbers of subjects (n = 11 to 259) . To see how Australians are responding to the guidelines and taking advantage of a range of reduced salt food products now in the supermarkets, we measured urinary sodium and potassium in 117 healthy adult subjects, mostly in the university community. In group N (nutrition personnel) sodium excretion averaged 128 mmol/d in females and 137 mmol/d in males. In group W (eating a western, traditional Australian diet, no special knowledge of nutrition) urinary sodiums averaged 133 mmol/d (female) and 159 mmol/d (male). In group A (eating an Asian diet) sodiums averaged 140 mmol/d (female) and 195 mmol/d (male). Potassium excretions were 73, 81, 72, 76, 53, and 65 mmol/day respectively in the six subgroups. We conclude that these results possibly reflect a small downward trend in Australian sodium intake and that sodium intake is lower in mainline Australian diets than Asian diets. But only a minority of subjects' urinary sodiums were within the recommended 40 to 100 mmol/d. Women excreted consistently smaller amounts of sodium than men; the guidelines for sodium should perhaps be expressed separately by gender. In six subjects who provided seven days' urine collections the coefficient of variation for sodium excretion was between 20 and 35%.

Objective To determine the cholesterol-lowering effect of ready-to-eat cereal containing soluble fibre as psyllium (86%), oatmeal and barley on the plasma lipids of otherwise healthy men with mild hypercholesterolaemia, who were already eating a diet low in saturated fats. Design Double-blind crossover trial, lasting 12 weeks, in volunteers eating each cereal for six weeks at home, in Sydney and Newcastle (New South Wales). Participants Eighty-one men (average age 50 years; range, 31-69 years) who had initial plasma (total) cholesterol concentrations of 5.8-8.8 mmol/L, but did not have major illness, obesity or diabetes, and were not on special diets or taking stool bulkers. Intervention One box of cereal was eaten each day: control, 60 g wheat/wheat bran (2 g soluble fibre); or test, 50 g of product containing psyllium/oats/barley (12 g soluble fibre). Subjects were allocated at random, when established on a low saturated fat diet, to wheat followed by psyllium cereal or psyllium followed by wheat cereal. Main outcome measures Plasma total cholesterol, high density lipoprotein cholesterol, triglyceride and low density lipoprotein cholesterol concentrations measured twice, four to seven days apart before the start of the trial and then after six weeks of eating each cereal. Results Compliance was excellent with both cereals. There were no significant differences in subjects' macronutrient intake or body weight between the two six-week periods. Total cholesterol and low density lipoprotein cholesterol concentrations fell significantly on psyllium cereal, relative to wheat cereal, in both periods at both centres (mean -3.2% and -4.4%, respectively). There were no consistent changes in triglyceride or high density lipoprotein cholesterol concentrations. Conclusions This type of product, which is easy to consume on a daily basis, is a useful adjunct to the dietary management of mild hypercholesterolaemia.

A single blood cholesterol measurement may not accurately reflect an individual's true mean concentration. If duplicate blood samples are taken, what number of days between sampling gives the best chance of detecting the maximum within-subject variation? In this study, we analyzed 20 serial blood samples obtained from each of 13 healthy, menstruating women over 35 days. Variability was calculated as the semivariogram, which gives the average squared difference between replicate samples taken over a range of sampling intervals. Data were available for a complete set of intervals from 1 to 26 days. Variability in total cholesterol (TC) increased as the interval between sampling increased from 1 to 12 days. With high-density lipoprotein cholesterol (HDL-C), variability increased from 1- to 7-day intervals. In practice, our results suggest that, irrespective of the time of menstruation, the minimal interval for collecting a second blood sample for TC and HDL-C assays is approximately 2 weeks.

An increase in dietary energy from carbohydrates is usually associated with a moderate increase in fasting plasma triglycerides--but not cholesterol--in the first weeks after the change. In the long-term the triglyceride returns to or to near the original concentration. Ordinary intakes of sucrose or fructose do not have any special elevating effect on plasma triglycerides in most normal and diabetic people, provided energy balance is not changed. Although biochemical theory predicts that fructose is more lipogenic than glucose, nearly all the animal reports of elevated plasma lipids with sucrose- or fructose-rich diets were obtained with diets unnaturally high in these sugars, and in rats and not other species. In humans, increased (fasting) triglycerides are observed with very high intakes, > 35% of energy from sucrose or > 20% of energy from fructose, and even then triglyceride elevation is unlikely unless the subjects are male and dietary fat is saturated. In people with hypertriglyceridemia (type IV), reduction of percent dietary carbohydrate is not recommended; this implies a higher percent of energy from fat, which leads to higher daylong triglycerides. However, in a minority of these patients, reduction of refined sucrose (or fructose) may be followed by lower triglycerides. Epidemiologically, high carbohydrate intakes are associated with low plasma cholesterol and variable plasma triglyceride concentrations.

Twelve healthy men were fed in turn three diets for 6 wk each in a 3 x 3 randomized block design: a control diet (essentially fish free), a fish diet (200 g lean Australian fish flesh/d), and the same fish-based meal but supplemented with 5 g fish oil/d. Dietary eicosapentaenoic acid [EPA, 20: 5n-3 (omega-3)] was strongly associated with erythrocyte membrane EPA (r = 0.908 at 6 wk), strengthening its value as a measure of compliance in fish and fish-oil feeding trials. On the fish diet, subjects had increased incorporation of n-3 polyunsaturated fatty acids (PUFAs) at the expense of n-6 PUFAs in their erythrocyte membranes. When the fish-based diet was supplemented with fish oil (5 g/d), there was a significant lowering of plasma triacylglycerol (-0.16 +/- 0.24 mmol/L; mean +/- SD). No change in plasma total cholesterol was detected although the fish + oil diet produced a reduction in very-low-density-lipoprotein cholesterol (-0.24 +/- 0.26 mmol/L).

Our group has compared plasma lipids in randomised crossover trials in which approximately half the fat intake of subjects was changed from palmolein to each of three predominantly monounsaturated oils in a series of experiments in free living volunteers. With canola oil total cholesterols were lower than on palmolein; part of this reduction was due to lower HDL-cholesterol (HDL-c) so that total cholesterol/HDL-c was only 2% lower. With olive oil mean total cholesterols were the same as on palmolein but HDL-cholesterols were a little lower and LDL-cholesterols a little higher. Plasma lipid fatty acid patterns confirmed the diet change, showing 5% higher 16:0 on palmolein and 11% higher 18:1 on olive oil. To test the possibility that lack of effect of the extra palmitic acid in the palmolein-olive oil comparison was because subjects were young, thin and active, comparison of a third oil, high oleic sunflower oil (HOSO) with palmolein was made in both young and middle-aged subjects. Plasma total and LDL-cholesterols were 7% lower in the whole group on HOSO but HDL-c was also 5% lower so total cholesterol/HDL-c was only 3% lower than on palmolein. There was no difference in lowering of LDL-c on HOSO between young and older subjects. In comparisons of all three predominantly monounsaturated oils with palmolein a higher HDL-c on palmolein reduced the presumed health benefit of lower total cholesterols on canola and high oleic sunflower oil. The reason for no reduction of total cholesterol on olive oil compared with palmolein was presumably due to the higher linoleic and higher phytosterols in palmolein and higher squalene in the olive oil.

Cereal grains and their products provide around 30% of total energy intake in British adults, (much more than any of the other major food groups). Coronary heart disease (CHD) is the largest single cause of death in Britain and many other Western countries. This review examines the question whether there is a relation between cereal consumption and CHD. Several of the nutrients in cereals have known potential for reducing risk factors for CHD: the linoleic acid, fibre, vitamin E, selenium and folate. Cereals also contain phytoestrogens of the lignan family and several phenolic acids with antioxidant properties. Processing generally reduces the content of these nutrients and bioprotective substances. Although cereals at the farm gate are very low in salt, processed cereal foods, eg bread and some breakfast cereals, are high-salt foods and thus could contribute to raising blood pressure. Human experiments have clearly shown that oat fibre tends to lower plasma total and LDL cholesterol but wheat fibre does not. Rice bran and barley may also lower cholesterol but most people do not eat enough barley to have an effect. Cereal foods with low glycaemic index such as pasta and oats are beneficial for people with diabetes and might lower plasma lipids. Between 1996 and 2001 an accumulation of five very large cohort studies in the USA, Finland and Norway have all reported that subjects consuming relatively large amounts of whole grain cereals have significantly lower rates of CHD. This confirms an earlier report from a small British cohort. The protective effect does not seem to be due to cholesterol-lowering. While cohort studies have shown this consistent protective effect of whole grain cereals, there has been (only one) randomised controlled secondary prevention trial of advice to eat more cereal fibre. In this there was no reduction of the rate of reinfarction. The trial had some weaknesses, eg there were eight different diets, compliance was not checked objectively, and duration was for only 2 y. It appears valid to make health claims (as now permitted by the US FDA) that whole grain cereal foods and oat meal or bran may reduce the risk of CHD.

In this era of evidence based medicine information about diet and diseases is less certain than information about drugs and diseases. Drug treatment is less complex. Dietary change can't usually be incorporated in a double blind trial. There is much more funding for pharmaceutical trials than for dietary trials. The following notes concentrate on newer, developing concepts.

Although “sugar causes heart disease” might become a little more fashionable after Pure, White and Deadly is reissued, the scientific data and constructs will not change. Evidence for the fat hypothesis is massive and has increased since Yudkin’s book went out of print. I think Watts conveys two wrong impressions about Yudkin’s disappointment that the sugar hypothesis was not confirmed.1 I was …

OBJECTIVE To estimate the incidence of Wernicke-Korsakoff syndrome (WKS) before and after the introduction of thiamine enrichment of bread flour in 1991. DESIGN Retrospective survey of hospital records. Patient records with the diagnostic codes for Wernicke's encephalopathy (WE) or Korsakoff's psychosis (KP) were reviewed and details of acceptable cases were entered onto a data form. SETTING All 17 major public general hospitals in the Sydney area (New South Wales), between 1978 and 1993. OUTCOME MEASURES Numbers of confirmed or probable diagnoses of WE, KP or WKS and associated deaths, patient demographic and social characteristics and alcohol intake. RESULTS 1,267 patients with WKS were found, with 1,012 acute cases. Although numbers of acute cases may have started to fall before 1991, numbers for the last two years were the lowest of all the 16 years (P = 0.004). Cases of KP outnumbered those of WE by about 3:1 and men outnumbered women 4:1. The peak age was 60-64 years (17%) and beer was the most commonly cited alcoholic drink (71%). The red-cell transketolase test was seldom used for diagnosis (3% of acute cases). CONCLUSIONS The lower number of "acute" cases in 1992 and 1993 is consistent with a preventive effect of mandatory enrichment of bread with thiamine, but is not conclusive evidence. Longer follow-up of Sydney hospitals, results of postmortem examinations and follow-up in other areas of Australia are required.

Twenty-one healthy normocholesterolemic young adults, men and women, completed a randomized 30-d/ 30-d crossover comparison of the effect of palmolein and olive oil on plasma lipids. The subjects were free-living volunteers who changed to low-fat diets to which one of the test oils was added (used as a spread, for baking, or for frying) in turn. Complete food records were kept throughout: the test oils were compared at 17% of total dietary energy. Under the conditions of this experiment plasma total and low-density-lipoprotein (LDL) cholesterol were almost identical with the two oils, so that when the palmitic acid (16:0) in palm oil replaced oleic acid (18:1) in olive oil the expected increase in LDL cholesterol was not seen. These results indicate that 16:0, though saturated, is not always a plasma cho- lesterol-raising fatty acid. Palmolein is rich in vitamin E, a-toco- pherol, and especially tocotrienols, but the latter were barely detectable in plasma. Am J ('liii Nutr 1995;61 :1043-51.

To determine the cholesterol-lowering effect of ready-to-eat cereal containing soluble fibre as psyllium (86%), oatmeal and barley on the plasma lipids of otherwise healthy men with mild hypercholesterolaemia, who were already eating a diet low in saturated fats.Double-blind crossover trial, lasting 12 weeks, in volunteers eating each cereal for six weeks at home, in Sydney and Newcastle (New South Wales).Eighty-one men (average age 50 years; range, 31-69 years) who had initial plasma (total) cholesterol concentrations of 5.8-8.8 mmol/L, but did not have major illness, obesity or diabetes, and were not on special diets or taking stool bulkers.One box of cereal was eaten each day: control, 60 g wheat/wheat bran (2 g soluble fibre); or test, 50 g of product containing psyllium/oats/barley (12 g soluble fibre). Subjects were allocated at random, when established on a low saturated fat diet, to wheat followed by psyllium cereal or psyllium followed by wheat cereal.Plasma total cholesterol, high density lipoprotein cholesterol, triglyceride and low density lipoprotein cholesterol concentrations measured twice, four to seven days apart before the start of the trial and then after six weeks of eating each cereal.Compliance was excellent with both cereals. There were no significant differences in subjects' macronutrient intake or body weight between the two six-week periods. Total cholesterol and low density lipoprotein cholesterol concentrations fell significantly on psyllium cereal, relative to wheat cereal, in both periods at both centres (mean -3.2% and -4.4%, respectively). There were no consistent changes in triglyceride or high density lipoprotein cholesterol concentrations.This type of product, which is easy to consume on a daily basis, is a useful adjunct to the dietary management of mild hypercholesterolaemia.

A single blood cholesterol measurement may not accurately reflect an individual's true mean concentration. If duplicate blood samples are taken, what number of days between sampling gives the best chance of detecting the maximum within-subject variation? In this study, we analyzed 20 serial blood samples obtained from each of 13 healthy, menstruating women over 35 days. Variability was calculated as the semivariogram, which gives the average squared difference between replicate samples taken over a range of sampling intervals. Data were available for a complete set of intervals from 1 to 26 days. Variability in total cholesterol (TC) increased as the interval between sampling increased from 1 to 12 days. With high-density lipoprotein cholesterol (HDL-C), variability increased from 1- to 7-day intervals. In practice, our results suggest that, irrespective of the time of menstruation, the minimal interval for collecting a second blood sample for TC and HDL-C assays is approximately 2 weeks.

Cerebrovascular disease (stroke) is the second cause of death and among the top five causes of morbidity in many developed and developing countries. The coincidence of trends of stroke and coronary heart disease mortalities is of question in different countries. This study aims to investigate patterns of increase and decrease of stroke mortality in 48 different countries. The mortality curves of stroke for 48 countries that had reliable data and met other selection criteria were examined using age-standardised death rates for 35–74 years from the WHO. Annual male mortality rates for individual countries from 1950 to 2005 were plotted and a table and graph were used to classify countries by magnitude, pattern and timing of stroke mortality. The natural history of stroke epidemics varies markedly among countries. Different stroke patterns are distinguishable; including “declining” (since the inception of data or 1950), “rise and fall”, “rising” (first part of epidemic), and “flat” (no epidemic yet). Further, epidemic peaks were higher in Asia, in particular Japan at 433/105, the former Soviet states at 388/105 and East Europe at 301/105 and lowest in Canada and Australia at 29/105. The different dates of mortality downturn could reflect the times when pharmaceutical treatment of hypertension started to be effective in sufficient numbers of the high risk population and/or there were significant changes in salt consumption. This could be translated to policy interventions for stroke control in countries with rising trend of the disease.

From the mid-1970s several groups realized progressively that the same amounts of carbohydrates in different foods produce quite different blood glucose curves after ingestion. The glycaemic index (GI) was introduced by Jenkins to express the rise of blood glucose after eating a food against a standard blood glucose curve after glucose (or white bread) in the same subject. The GI ranges from about 20 for fructose and whole barley to about 100 for glucose and baked potato. A table is given of representative GI values. There appears to be no general correlation between GI and per cent resistant starch in foods. Questions about methodology for GI are discussed and the factors in food that affect glycaemic response are briefly reviewed. The GI is affected by the physical form of a food, by processing and by associated fat in the food, which reduces the GI, presumably by delayed gastric emptying. As a rule the degree of insulin response to carbohydrate-containing foods is similar to the glycaemic response. Most investigators have found that the GI of a meal of mixed foods can be predicted from the (weighted) GI of its constituent foods. The GI concept is proving useful in dietary design for the management of diabetes mellitus, especially the non-insulin-dependent type. It may prove useful for prevention of diabetes and perhaps also in pre-event meals for athletes, as a factor in dental cariogenesis, in determining satiety, and conceivably regular low GI foods could delay ageing by reducing glycosylation of body proteins.

Over the last four decades there has been extensive research into the links between diet and coronary heart disease. The most recent literature is reviewed in this position statement. The clinical and public health aspects of the National Heart Foundation's nutrition policy are based on this review. The key points are as follows: 1. Saturated fatty acids A high intake of saturated fatty acids is strongly associated with elevated serum cholesterol and LDL-cholesterol levels and increased risk of coronary heart disease. 2. The n-6 polyunsaturated fatty acids The n-6 polyunsaturated fatty acids (principally linoleic acid) lower serum cholesterol levels when substituted for saturated fats and probably have an independent cholesterol-lowering effect. 3. The n-3 polyunsaturated fatty acids (fish oils) The n-3 polyunsaturated fatty acids reduce serum triglyceride levels, decrease the tendency to thrombosis and may further reduce coronary risk through other mechanisms. 4. Monounsaturated fatty acids Monounsaturated fatty acids reduce serum cholesterol levels when substituted for saturated fatty acids. It is not clear whether this is an independent effect or simply the result of displacement of saturates. 5. Trans fatty acids Trans fatty acids may increase serum cholesterol levels and can be reckoned to be equivalent to saturated fatty acids. 6. Total fat Total fat intake, independent of fatty acid type, is not strongly associated with coronary heart disease but may contribute to obesity. Associations between total fat intake and coronary heart disease are primarily mediated through the saturated fatty acid component. 7. Dietary cholesterol Dietary cholesterol increases serum cholesterol levels in some people and may increase risk of coronary heart disease. 8. Alcohol A high intake of alcohol increases blood pressure and serum triglyceride levels and increases mortality from cardiovascular disease. Light alcohol consumption reduces the risk of coronary heart disease. 9. Sugar The consumption of sugar is not associated with coronary heart disease. 10. Sodium and potassium High salt intake is related to hypertension especially in the subset of "salt-sensitive" people. Potassium intake may be inversely related to hypertension. 11. Overweight and obesity Abdominal obesity increases the risk of coronary heart disease probably by adversely influencing conventional risk factors. 12. Vegetarianism A high intake of plant foods reduces the risk of coronary heart disease through several mechanisms, including lowering serum cholesterol and blood pressure levels.

One of the major postulates of the dietary fibre hypothesis (Trowell, 1972) was that coronary heart disease (CHD) is associated with diets low in fibre and a high-fibre diet may protect against CHD. The most obvious direct mechanism for such an effect is by reduction of plasma total and LDL-cholesterol, presumably by some interference with sterol metabolism which would have to start in the gastro-intestinal tract, since fibre is by definition indigestible (by human enzymes) and so not absorbable as such. It is difficult to visualise how any other direct mechanism could work, such as a reduced tendency to thrombosis, reduced blood pressure or reduced liability to dangerous cardiac arrhythmias, from eating more dietary fibre.

Objective To compare high- and low-glycemic index (GI) diets in the treatment of non-insulin-dependent diabetes mellitus (NIDDM). Research Design and Methods Sixteen subjects with well-controlled NIDDM and normal lipid profile, 10 of whom continued oral hypoglycemic medication, participated in the study. A diet that emphasized low-GI foods (e.g., porridge, pasta) was compared with a high-GI diet (e.g., processed cereals, potatoes). The GI of the low-GI diet was 15% lower than the high-GI diet (77 ± 3 vs. 91 ± 1) but otherwise similar in macronutrient composition and fiber, as determined by a 4-day weighed record. The diets were instituted under instruction from a dietitian who visited subjects at home on a weekly basis. Body weight was maintained within 1–2 kg. Results Glycemic control was improved on the low-GI diet compared with the high-GI diet (statistically significant findings, P < 0.05). Mean glycosylated hemoglobin at the end of the low-GI diet was 11% lower (7.0 ± 0.3%) than at the end of the high-GI diet (7.9 ± 0.5%), and the 8-h plasma glucose profile was lower (area under the curve above fasting 128 ± 23 vs. 148 ± 22 mmol.h-1.L-1, respectively). Mean fasting plasma glucose, total cholesterol triglycerides, and lipoproteins did not show important differences. Conclusions A low-GI diet gives a modest improvement in long-term glycemic control but not plasma lipids in normolipidemic well-controlled subjects with NIDDM.

Twenty-one patients undergoing regular hemodialysis completed a trial of energy supplementation. Nine patients added the glucose polymer Polycose to their usual diet and 12 acted as control subjects. The supplemented patients were asked to incorporate 100 or 150 g polymer, equivalent to 1600 or 2400 kJ (400 or 600 kcal) into their usual diet, daily for 6 mo. This resulted in a mean increase in energy intake of 1630 kJ (p less than 0.05) and a mean weight gain of 3.1 kg (p less than 0.005). The addition of glucose polymer to the diet resulted in a mean increase in body fat of 1.8 kg and the lean body mass increased by 1.3 kg. No significant effect on plasma triglycerides, urea, or creatinine was detected. The intake of macro- and micronutrients was not adversely affected and no clinical or psychological side effects were reported. Follow-up of these patients showed that the weight gain was maintained after 6 mo. Glucose polymer was an effective energy supplement that had beneficial effects on the nutritional status of hemodialysis patients.

The total body protein status of 18 patients undergoing regular haemodialysis was assessed by measuring total body nitrogen (TBN) using in vivo neutron activation analysis (NAA). Eighteen healthy controls, who were selected according to their height, age and sex match with the patients were also measured. The male and female patients were both found to have lower mean values for total body protein (P less than 0.01, P less than 0.025 respectively) although they had similar weights compared with their matched controls. Seven patients were measured on further occasions and only two patients showed a change in their body protein. One female showed an increase of 11 per cent in body protein (with an increase of 25 per cent in body weight) after intensive nutritional repletion therapy. In vivo NAA provides a direct means of measuring body protein and is a reliable method to monitor changes with treatment regimes.

Thiamin is one of the marginally adequate nutrients in the Australian diet. The incidence and prevalence of Wernicke-Korsakoff syndrome in this country may be the highest in the world. Homeless men could be at risk for low intakes of thiamin in association with irregular high alcohol intakes. A sample of 107 homeless men from two hostels and one clinic for homeless persons in inner Sydney was investigated for nutritional status; their thiamin status is reported here. By means of 24-hour recall methods, their mean dietary thiamin intake--0.76 mg per day--was less than the National Health and Medical Research Council's recommended dietary intake of 1.1 mg per day; at 0.076 mg/MJ it was even less than the minimal requirement of 0.08 mg/MJ. It was much lower than the mean intake of 1.38 mg per day that was found in the 1983 National Dietary Survey of adults and the distribution of thiamin intakes in this study was skewed positively, with the largest intake being in the range of 0-0.1 mg per day. On clinical examination we found a high prevalence of signs that were consistent with thiamin deficiency. Twenty-four per cent of the subjects showed three-or-more of the signs of the Wernicke-Korsakoff syndrome (ophthalmoplegia, nystagmus, ataxia, peripheral neuropathy and global confusion). In assaying for red-cell transketolase levels, this subgroup showed higher thiamin pyrophosphate effects than did the whole sample. Thirty-six per cent of the whole sample showed subnormal thiamin status by the thiamin pyrophosphate effect. Thus, in this sample, homeless men showed a high prevalence of dietary, biochemical and clinical features to indicate subclinical or early clinical thiamin deficiency.