Plant power

Fact: cholesterol is a killer. Well, no, actually, not in moderation.

The problem is, cholesterol is in tasty foods with lots of animal fat like red meat, cheese, cake and pies. Many of us find them hard to resist and desire guilt-free indulgence. So food manufacturers that want to win the hearts of health-conscious consumers could be on to a winner with cholesterol-busting plant sterols and stanols, known as phytosterols.

According to Frost & Sullivan, revenues in the European phytosterols market reached $184.6M in 2005 and will hit $395.2M by 2012, buoyed by food and drink applications. The analyst reckons the only thing that may stifle growth is confusion caused by information overload about nutrition. However, effective marketing and government campaigns about how phytosterols aid heart health should help to offset this.

Cholesterol is one of a group of substances called sterols that help to maintain a good balance of fats in the body. It is a waxy fat, or lipid, produced by the liver and is found in the blood. We need cholesterol because it helps the body to absorb fats from food. We need some fat for general health.

The problem is, we eat too much, which is leading to rising rates of cardiovascular disease. The World Health Report 2004 says 225M people in the EU have high cholesterol and this will increase by 20% in a decade. The beauty of plant sterols is that they prevent cholesterol being absorbed into the body via the small intestine. The unabsorbed cholesterol and plant sterols are excreted through the digestive tract.

Risky business

A high level of cholesterol - above five millimoles per litre of blood - is one of the main risk factors for coronary heart disease. Too much 'bad' cholesterol - low density lipoprotein (LDL) - clogs the arteries. 'Good' cholesterol - high density lipoprotein (HDL) - mops up excess LDL. Plant sterols do not affect the level of HDL in the body.

People with well-balanced diets already eat plant sterols because they are in fruits, nuts, seeds and vegetables. They can also be found in rapeseed and soybean oil. Plant stanols, which are absorbed from eating grains, can also be derived from sterols.

Plant sterols are available in two forms: as pure sterols or esters with fatty acids. "Plant sterol ester has no special taste or flavour and it's heat stable, so it's a good ingredient for use in foods," says Anniina Honkanen, product manager for Raisio Benecol.

Pure plant sterols have a high melting point of 140°C, which makes it hard to use them in food and drink, explains Dr Franz Timmermann, global product line manager for Vegapure plant sterols and sterol esters at ingredients supplier Cognis. However, the advantages are that they are stable against oxidation and they don't contain additional fat.

He continues: "Plant sterol esters are more susceptible to oxidation and it's recommended that they're stored under cool conditions. Their advantages are a lower melting point and much better solubility in fats and oils. The selection of the most appropriate form will often depend on the specific application."

Chris Swire, commercial director at independent dairy company Fayrefield Foods, says some products may impart a flavour if they use ingredients that help to evenly distribute sterols throughout the finished product.

Fayrefield recently launched Heartfelt Plus, a 12% fat cheese that contains Reducol, developed by Canadian firm Forbes Medi-Tech. "Reducol can affect the way products feel in the mouth by giving them a slightly thicker, creamier texture in virtually fat-free yoghurt or fermented milk," says Swire.

Technically, plant sterols can be added to any type of food and drink, except mineral water. Timmermann explains this is because manufacturers have not yet discovered how to transform sterols into a water-soluble form that can be used in an effective, cholesterol reducing dose.

There have been many clinical studies worldwide into the positive effects of foods that contain phytosterols. The British Heart Foundation says it has shown there are no adverse effects from taking plant sterols and stanols for one year. However, it believes longer-term research involving a large number of people is necessary. It also says no studies have examined their effect on pregnant women.

Barriers to entry

In June, Heart UK's international symposium on atherosclerosis reported that plant sterols may cut LDL by up to 15% (2.5g daily is the recommended dose). They have a minor side effect of reducing levels of beta-carotene in the body, but this can be overcome by eating more fruit and vegetables. The Rome conference also heard that companies are exploring the use of sterols in grains, orange juice, lemonade and ground beef.

Dr Michelle Jones, European technical manager with ADM Natural Health and Nutrition, says: "Their use isn't restricted by technological difficulties, but rather by a restricted list of products to which they may be added in some markets." Phytosterols must be used in accordance with the EU's Novel Food Regulation, which the European Commission (EC) intends to revise next year.

Ingmar Wester, vice president, regulatory and scientific adviser at Raisio Benecol, says changes to EU regulations will result in more investment into proving health benefits. "There will certainly be an impact on spending on clinical research to obtain strong enough scientific evidence about product safety and effectiveness."

Foods that do not have a significant history of consumption within the EU before 1997 are novel foods. Certain plant sterols are now approved as novel ingredients in margarines, salad dressings, dairy and soya drinks, fermented yoghurt-type products, reduced fat cheese and rye bread. According to the Food Standards Agency, phytosterols are not novel foods when used in capsules because they were taken in this form before 1997.

"The position of phytosterols in functional foods is ambiguous and needs clarifying," says Neil Forbes of Cornelius Health and Nutrition, UK distributor of the ChoLevel phytosterol. He continues: "A case can be made that if phytosterols were consumed in the EU before 1997, they aren't novel foods. However, several companies have submitted novel food applications for phytosterols or foods that contain them. The status of phytosterol esters is less equivocal and these materials are generally understood to be novel foods."

Companies in the US can use plant sterols in many products, including mayonnaise, pasta and noodles, healthy bars, salty snacks, puddings, ice cream, cheese and juices.

There, manufacturers have two ways to introduce a new food ingredient: by filing a food additives petition for the ingredient, or showing the Food and Drug Administration that it is 'generally recognised as safe' (GRAS). "Recent GRAS approvals may act as a potential catalyst to similar developments in other countries," comments Jones.

The UK, where heart disease is the biggest killer among adults, is seen as a key target for plant sterols and functional foods. "It's still undeveloped compared to some countries in mainland Europe," says Forbes. For example, food containing Co-enzyme Q-1O, a natural vitamin-like substance that acts as an antioxidant, is already available in Slovenia but not Britain. Studies have shown that Co-enzyme Q-10 may be beneficial for heart health.

"The UK represents by far the largest opportunities, although other European countries are showing increasing interest," comments Swire. Timmermann says western Europe is still the biggest market for plant sterols, but eastern Europe will soon have more functional foods too.

Healthy repositioning

In the future, European consumers may see plant sterols in a wider range of foods, including soya milk, sauces and mayonnaise.

Forbes says: "They may be increasingly found in lifestyle foods like nutritious bars and could complement the use of over-the-counter medicines used to control cholesterol levels. Healthier, low fat versions of crisps have been appearing and phytosterols could help with the repositioning of these foods in the market."

Consumer interest in maintaining heart health should ensure people won't be put off by the premium price of such products. "Phytosterols are ideal for added value products," says Forbes. "Inexpensive foods such as spreads have been transformed into high value speciality foods using phytosterols. The commercial success of these products proves that consumers will buy on value, not price, so it's difficult to conceive of an application for which phytosterols may be too expensive."

Timmermann agrees. "We can't see that any food application would be too expensive. Since the effective daily intake is 2-3g a day, the cost of the finished product will mainly depend on the serving size." For example, fermented one-shot drinks and nutrition bars are among the most expensive, and yet they have already proved successful. Pass the cheese, please.