May 2005 Newsletter

Prof Mark Wahlqvist AO, MD, FRACP

Welcome to the May edition of the HEC newsletter. This edition looks at scientific studies published on: the EPIC study and the mediterranean diet, cheese, red meat, tomatoes, acrylamide and heart disease risk factors of Australians.

Dr Antigone Kouris-Blazos PhD, Grad Dip Diet, BSc (Hons)

WHAT'S NEW IN NUTRITION RESEARCH

EPIC STUDY : the longevity benefits of the mediterranean food pattern proven once again to work in both mediterranean and non-mediterranean seniors

The Mediterranean food pattern is characterised by a high intake of vegetables, legumes, fruits, and cereals (in the past largely unrefined); a moderate to high intake of fish; a low intake of saturated fats but high intake of monounsaturated fats, particularly olive oil; a low to moderate intake of dairy products, mostly cheese and yogurt; a low intake of meat; and a modest intake of ethanol, mostly as wine.

Adherence to a Mediterranean food pattern has been measured using a 10 unit dietary score developed by Professor Antonia Trichopoulou in conjunction with HEC's Dr Antigone Kouris-Blazos and Professor Mark Wahlqvist. This score was first published in the British Medical Journal in 1995 (Trichopoulou A, Kouris-Blazos A, Wahlqvist ML et al. Diet and overall survival in elderly people. BMJ 1995; 311: 1457-60 ) and was the first study to show that a mediterranean dietary pattern improves overall survival in elderly Greeks in Greece.

This score was then applied by the same researchers to elderly Anglo-Celtic Australians, Greek Australians, Swedes and Japanese and for the first time showed that longevity benefits could be obtained by non-mediterranean people following a more mediterranean food pattern (Kouris-Blazos, Gnardellis, Wahlqvist et al., Advantages of the Mediterranean diet transferable to other populations? A cohort study in Melbourne, Australia. British Journal Nutrition 1999; 82: 57-61; Wahlqvist ML, Darmadi-Blackberry I, Kouris-Blazos A et al. Does diet matter for survival in long-lived cultures? Asia Pac J Clin Nutr 2005; 14 (1): 2-6)..

The recent study published in the British Medical Journal 2005 by our colleague Professor Trichopoulou once again proves not only the longevity benefits of the mediterranean food pattern (using our original score published in the BMJ in 1995) but that these benefits can also be experienced by non-mediterranean people. more

Cheese does not raise blood cholesterol as much as butter?

Saturated fat is well known to raise blood cholesterol levels - that is why high fat animal foods such as butter and fatty cheeses are usually restricted when one is trying to lower their blood cholesterol. But do all animal foods raise blood cholesterol equally? Apparantly not, according to a Norwegian study.
This 3 week feeding study on 22 adults, published in the British Journal of Nutrition in November 2004 (Biong AS et al) showed that consuming a diet containing about 160g cheese per day (about 8 thin slices) elevated blood cholesterol less than consuming a diet containing 55g butter per day (about 3 tablespoons) even though saturated fat intake was the same on both diets. more...

Is red meat bad for the heart?

Li and colleagues (including HEC's Professor Wahlqvist) reviewed 54 studies from the scientific literature in relation to red meat consumption and heart disease risk factors. Substantial evidence from recent studies shows that lean red meat trimmed of visible fat does not raise total blood cholesterol and LDL-cholesterol levels. Dietary intake of total and saturated fat mainly comes from fast foods, snack foods, oils, spreads, other processed foods and the visible fat of meat, rather than lean meat. In fact, lean red meat is low in saturated fat, and if consumed in a diet low in saturated fat is associated with reductions in LDL-cholesterol in both healthy and hypercholesterolemia subjects. Lean red meat consumption has no effect on in vivo and ex vivo production of thromboxane and prostacyclin or the activity of haemostatic factors. Lean red meat is also a good source of protein, omega-3 fatty acids, vitamin B12, niacin, zinc and iron. In conclusion, lean red meat, trimmed of visible fat, which is consumed in a diet low in saturated fat does not increase cardiovascular risk factors (plasma cholesterol levels or thrombotic risk factors).
This review was published in Asia Pacific Journal of Clinical Nutrition vol 14, issue 2, 2005

Is the antioxidant 'lycopene' better absorbed from cooked tomatoes in the presence of olive oil?

Lycopene is the main carotenoid in tomatoes and it has been hypothesised to be responsible for reducing the risk of some cancers and heart disease. The cooking of tomatoes with olive oil is a characteristic combination in the Southern Mediterranean diet. Previous studies have shown that the absorption of lycopene is greater from processed tomatoes than fresh tomatoes, since the processing breaks down the tomato cell matrix and makes the lycopene more available. The aim of the present study was to determine whether consumption of diced tomatoes cooked with olive oil resulted in higher plasma lycopene concentrations than consumption of diced tomatoes cooked without olive oil. Plasma lycopene concentrations were measured after 5 days on a low lycopene diet and again after a five-day dietary intervention, in healthy subjects, who consumed one meal per day of tomatoes (470 g) cooked with or without extra virgin olive oil (25 ml olive oil). There was an 82% increase in plasma lycopene concentrations in the 11 subjects who consumed tomatoes cooked in olive oil. There was no significant change in plasma lycopene in 12 subjects consuming tomatoes cooked without olive oil. This study showed that the addition of olive oil to diced tomatoes during cooking greatly increases the absorption of lycopene. The authors (Fielding et al) highlight the importance of cuisine (i.e how a food is prepared and consumed) in determining the bioavailability of dietary carotenoids such as lycopene.
This study was published in Asia Pacific Journal of Clinical Nutrition vol 14, issue 2, 2005

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