Spreading a message about healthy hearts

By MARTIN JOHNSTON

Supermarket fridges can be baffling places for shoppers who want to help their heart by choosing the right sort of fat to scrape onto their morning toast.

Health specialists have been down on butter and its cholesterol-raising power for decades, steering us to the margarine stack.

But with margarines there is yet another choice to be made, now that some contain plant sterols. Reputable health groups say they can drive blood-cholesterol levels even lower than traditional polyunsaturated margarines can.

Bill Schrapnel, a former national nutrition manager of the Australian Heart Foundation, has written a book, The Pro-active Plan, about plant sterols and a cholesterol-lowering diet.

In New Zealand last week to promote the book, he said the now-traditional approach to cholesterol reduction was to cut the intake of saturated fat, contained in butter and meat fat, and to increase polyunsaturated fat. That could reduce the level of "bad" cholesterol in the blood by up to 10 per cent, although in reality most people achieved around 6 per cent.

Eating plant-sterol-enriched margarine reduced blood cholesterol a further 10 per cent on average, he said, citing scientific studies published in the late 1990s. The amount needed was the quantity normally spread on three or four slices of bread a day.

"It's a remarkable reduction for such a simple intervention."

High blood cholesterol is a risk-factor for heart disease. Cholesterol can build up inside heart arteries as plaque which can break off, leading to a blood clot and possibly a heart attack.

Cholesterol is the most common animal sterol. Plant sterols occur in the greatest amounts in nuts and seeds. In the gut, they bind to cholesterol, preventing it from being absorbed. But plant-sterol-enriched spreads are pricey. They can cost more than four times the price of standard margarines - $5.45 for 250g at one supermarket - partly because of their rarity. It takes 2.5kg of vegetable oil to produce 1g of plant sterols.

The Heart Foundation confirms the research findings cited by Mr Schrapnel.

It said the enriched spreads could be used alongside cholesterol-lowering drugs to boost the impact on cholesterol, but the foundation warns patients to keep using their medication as directed by their doctor.

It says plant sterols offer an extra option to those at risk of heart disease, but notes that the degree of reduction in heart disease is yet to be demonstrated in long-term studies.