As a nation in search of better health, we are increasingly turning to functional foods and drinks – nutriceuticals, as they are known in the trade – such as the cholesterol-lowering spread Flora pro-activ, to supplement our diets. Last year we forked out around £375 million on the promise that these will bring better health.
With a turnover of £75 million a year and more than 50 per cent of the market, Flora pro-activ is the UK’s leading cholesterol-lowering spread. It contains a high percentage of plant-based fats known as plant sterols, which medical research shows can reduce levels of ‘bad’ or low density lipoprotein (LDL) cholesterol – the kind that clogs arteries.
Sterols belong to a group of chemicals that include the hormone estradiol, as well as other steroid hormones, vitamin D (cholecalciferol) and cholesterol (note the –ol ending in each name). The average Western diet contains only small amounts of plant sterols – around 250-500 mg per day. At these levels they appear to have little effect on cholesterol. But at higher levels, and with regular use, they reduce the absorption of cholesterol from the gut, with the knock-on effect of lowering concentrations of cholesterol in the blood.
Their benefits seem impressive at first glance. Approximately 3g daily can reduce LDL cholesterol levels by an average of 14 per cent within a few weeks– more than can usually be achieved through diet alone. But by focusing solely on the cholesterol-lowering ability of plant sterols, we may have overlooked some of the potential problems associated with their use.
Plant sterols can be derived from vegetable oils such as soya, canola and sunflower (this is the case with Flora). They can also come from the waste material from wood pulping – a potentially more toxic option to which food manufacturers are increasingly turning, as the demand for sterol additives increases.
Either way, the sterols in your spread are not in their natural state. Because they are not freely soluble in oils and fats, the sterol is first hydrogenated and then compounded, or esterified, with other fatty acids (usually from rapeseed oil) in order to make them mix better in the spread.
The next concern is about the pseudo-hormonal effects of sterols. Not long before the US Food and Drug Adminbistration (FDA) first approved the use of sterols in foods, a Swedish review in 1998 made the chilling and largely ignored observation that “further studies are required of [their] phyto-oestrogenic and endocrine effects, and [their] effects on growing children, particularly regarding subsequent fertility in boys.
This research in humans still has not been done and monitoring of potential hormonal effects in regular users is likewise missing. Apologists describe the oestrogenic activity of plant sterols as weak and insignificant and extrapolated largely from animal studies.
But as far back as 1975, research identified the structural similarity between plant sterols and the morning-sickness drug Diethylstilboestrol, another ‘weak’ oestrogen associated with birth defects and reproductive cancers in women. Both in the laboratory and in the wild, plant sterols have been shown to provoke the growth of breast cancer cells and alter sex hormone levels in animals. Fish that live downstream from paper mills are routinely found to change sex due to exposure to sterol-containing effluents.
Because of all the unknowns abouoestrogenic potential in humans, Flora and other sterol-containing products are legally required to carry a warning that ‘pregnant and breastfeeding women and children should not use this product’, as well as a recommendation not to exceed the recommended 3g of plant sterols daily (equivalent to three 20g servings of Flora pro-activ a day).
Another important and quantifiable concern about plant sterols is that they reduce the absorption of some essential fat-soluble vitamins, especially beta carotene. Eating more fruit and vegetables would counter the decreased absorption of these vital nutrients – however, eating more fruit and vegetables in the first place would also lower your cholesterol levels, negating the need for a functional spread. It is worth noting that Flora pro-activ includes extra beta carotene, as well as vitamins E and D – not as an extra added health bonus but to counter the vitamin depleting effect of the active ingredients.
While plant sterols have some benefits, they are not long-term solutions to anything and their use does nothing to encourage genuinely healthy eating. Consumption of plant sterols needs to be considered in the overall picture of a person’s consumption of other terol-containing foods – such as corn, wheat, rye, oat and olive oil, as well as beer and bourbon, borderline nutriceuticals such as soya, and the increasing variety of herbal medicines including wild yam, saw palmetto, pygeum, devil’s claw, gingko biloba, Panax and Siberian ginseng, each of which owe their beneficial actions in part to their plant sterol components.
As they are added to more and more foods, the chance of inadvertent overconsumption– and the potential health problems of this – grows more likely.
Dietary sources of sterols
Using Flora pro-active will produce a higher cholesterol-lowering effect than could be achieved through diet alone, but not more than could be achieved using a combination of healthy diet and regular exercise. Furthermore, dietary modification and exercise produce long-term effects, while the effect of plant sterols lasts only as long as you continue to take them. Stop using Flora pro-activ and your cholesterol will return to previous levels.
There is no such thing as sterol deficiency, and with a few modifications most of us can get all the plant sterols we need from our diets. On average, 100g of fresh vegetables contain between 5 and 40 mg of plant sterols. Fresh fruit contains between 2 and 30 mg of plant sterols per 100g. Nuts and seeds, however, are the richest sources – sprouting seeds can have up to 120mg sterols per 100g.
Their ubiquity in fruits and vegetables could be taken as evidence that what many nutritionists have been saying for years may actually be true – that the hunter-gatherer diet, which contains a high level of plants and seeds, may really be the one that healthy humans were meant to eat.
INGREDIENTS: Water, vegetable oils (including sunflower oil), plant sterol esters (12.5%), modified tapioca starch, salt (1.0%), buttermilk Emulsifiers: Mono- and di-glycerides of fatty acids, sunflower lecithin, Preservative: Potassium sorbate, citric acid, vitamin E, flavouring, vitamin B6, folic acid Colour: Beta carotene, Vitamins A, D and B12
PLANT STEROL ESTERS: Cholesterol-lowering additive.
Interferes with absorption of some fatsoluble vitamins, principally carotenes. Potential hormone disrupters. Not proven safe for children or pregnant women.
VEGETABLE OIL: Basic ingredient. The description on the label, “including sunflower oil” suggests that Flora is a mix of different oils. This mix can change from batch to batch according to the market price of the various oils. Most vegetable oils in processed foods are based on corn or sunflower oil, high in omega-6 fatty acids. Over-consumption of omega-6 is linked to cancer, immune system damage, hormone imbalance, heart disease and stroke.
MONO- AND DI-GLYCERIDES OF FATTY ACIDS (E471), SUNFLOWER LECITHIN: Emulsifiers. This spread is a mixture of oil and water. Emulsifiers hold the mix together. Fatty acid esters are also commonly used in junk foods to keep them from getting stale. Flora’s use of sunflower lecithin is in response to consumer worries about the GM status of the world’s soya. Sunflower products tend to be GM-free.
MODIFIED TAPIOCA STARCH: Thickener, stabiliser. Modified food starch is a starch that has been treated physically or chemically to modify one or more of its properties. This all-purpose thickener is derived from cassava root or yucca plants and is at home in spreads as it is in adhesives, explosives, paper manufacture, and textile finishings. It is not a substance found in nature, it adds no nutritional value and there is no information on its health effects.
FLAVOURINGS: Adds taste. Flavourings can be mixes of several synthetic chemicals. Essentially perfumes by another name, they will be derived from petrochemicals and contain the same range of neurotoxins, carcinogens and allergens as found in all perfumes.
This article first appeared in the Ecologist April 2007