A lovely spread

Jemima Hodkinson looks at the history of what we’ve spread on our bread – and what’s best for our health

Butter is ancient. Humans have been churning milk and cream into a fatty spread for thousands of years – almost since we’ve had stone-age bread to spread it on. But over the last 150 years, there has been a battle for the butter knife on our breakfast tables.

What is margarine and where did it come from?

Margarine, made using simple chemistry to turn ‘healthy’ oils into solid spread, gained popularity in the 20th century with claims that it could save our hearts, one slice of toast at a time. Consumers began eschewing butter, which is high in saturated fat, in their droves. Today, new evidence questioning the link between saturated fats and heart disease has put butter and other animal-fat spreads firmly back on the table, but conflicting research and advertising claims continue to confuse consumers: so what is the healthiest spread for your sandwich?

Margarine was invented in 1869 by a French food chemist, Hippolyte Mège-Mouriès, in response to a request made by Napoleon III for a cheaper substitute for butter to feed poorer French citizens and sailors in his Navy. Mège-Mouriès’s invention bore little resemblance to today’s spreads: it was a pasty white substance, made by churning beef tallow (fat that has been rendered from beef) with milk. It had little success in his lifetime. After his death, a Dutch company developed the recipe and added a crucial ingredient, yellow dye, to make it appear more similar to real butter.

Around the turn of the 20th century, recipes using cheap plant oils rather than animal fat began to emerge and sales crept up. However, as the popularity of margarine (also known as ‘oleomargarine’ or ‘butterine’) increased, so did opposition from dairy farmers wary of the threat to the butter industry. Heavy taxes were applied in the USA and Canada. Some US states restricted the use of yellow dyes in margarine, or even insisted that it be dyed an unappetising pink, brown or red to distinguish this synthetic spread from butter.

Dairy shortages during World Wars I and II led more consumers to try margarine, out of necessity. But it was only in the mid-20th century – when manufacturers began trumpeting its heart-healthy qualities – that the popularity of margarine skyrocketed.

What’s in butter and margarine?

The vegetable oils in margarine are rich in unsaturated fat, whereas butter and other animal fats contain a high percentage of saturated fat. At the time, the general nutritional consensus was that that eating saturated fats increased levels of low-density lipoprotein (LDL) cholesterol (‘bad’ cholesterol) in the blood, which causes arteries to harden and narrow and can lead to coronary heart disease. Adverts pointedly asked, “Ought you to be eating Flora?” Margarine was the key to “leading a healthier way of life”, for the man who “cares about what he eats”. The slogans worked: in the late 1950s, margarine consumption overtook butter in the USA, with consumption peaking in 1976 at nearly 5.4 kg per person per year.

However, in recent years consumer preferences have switched again, partly thanks to new insights into the health risks posed by different types of dietary fat.

In order to turn liquid vegetable oil into solid margarine, it is mixed with hydrogen gas and a catalyst at a high temperature to undergo a reaction called hydrogenation. The fatty acid chains in the oil molecules contain double bonds between the carbon atoms, meaning the fat is unsaturated. Hydrogenation converts these bonds into single bonds, raising the melting point in the process. However, this only partially hydrogenates the oil. The remaining unsaturated bonds are flipped so that the carbon chain extends from opposite sides of the double bond, to the trans configuration, to produce what’s known as trans fat.

This simple change to the molecules causes them to behave very differently in our bodies. Research carried out in the 1990s showed that these trans fats raise the level of ‘bad’ LDL cholesterol and lower the level of ‘good’ high-density lipoprotein (HDL) cholesterol in the blood, with a consequent increase in the risk of coronary heart disease. Suddenly, the health claims of margarine were in jeopardy.

What do we know today about fats?

Recent research has further diminished margarine’s position as a healthy alternative to butter by challenging the assumption that saturated fats (like those in animal fats) pose a threat to heart health. For example, a review of 72 studies involving over 100,000 people found that there was no evidence that saturated fat increases the risk of coronary heart disease, or that unsaturated fat protects you from it.

Partly as a result, today butter is firmly back on the menu – US consumption has outstripped margarine since the mid-2000s. This is also a symptom of a shift in preferences away from ‘processed’ foods, as well as more general changes in attitudes towards the role of fat in our diets.

Fats were once demonised as a high-calorie, heart-busting luxury, but now the health benefits of cutting fats from the diet are being questioned. Margarine has further suffered from the increasing popularity of alternatives such as nut-based spreads, olive oil spreads and use of liquid olive oil; even dripping and other animal fats appear to be making a comeback in the spirit of nose-to-tail eating (where all edible parts of an animal killed for food are used).

The margarine industry has responded by attempting to re-establish its health-food credentials, removing trans fats from the spreads and sometimes adding ingredients, such as plant sterols and stanols, that have been shown to lower LDL cholesterol.

Which spread should we be eating?

So, after all of the advertising claims, what should we be spreading on our morning toast? The total fat content of butter and most margarine is actually quite similar – around 80 per cent – although in butter, the majority of this is saturated fat, whereas margarine contains more unsaturated fats. They also have roughly the same calorie content (around 700 calories per 100 g), although reduced-fat and low-fat varieties of margarine are available.

Most margarine has now cut out all harmful trans fats. ‘Wholesome’ butter can’t always claim to be entirely unadulterated, either – like margarine, it is sometimes dyed to appear a richer shade of buttery yellow. There are environmental concerns too: the ‘vegetable oil’ used to make margarine may in some cases include palm oil. Palm oil is laden with controversy as it linked to deforestation in Indonesia, Malaysia and Thailand, where trees are cut down to make way for enormous palm plantations.

Of course, for some of us, including vegans and lactose-intolerant people, the choice is predetermined as margarines and spreads offer a dairy-free alternative. For others, taste is the deciding factor. Many consumers have decided that they can believe it’s not butter, and have voted with their taste buds. But with new spreads developing alongside our understanding of the nutritional significance of fats, no doubt our tastes could change again.

Lead image:

Steve Leggatt/Flickr CC BY NC ND

References

Questions for discussion

  • What is ‘vegetable oil’? How is it produced?
  • What parts of a plant contain oil? What is the role of oils in plants?
  • Why do we need fat in our diet?
  • In our diets, what are the main sources of: a) saturated fat? b) unsaturated fat?

Further reading

Downloadable resources

About this resource

This resource was first published in ‘Fat’ in December 2015.

Topics:
Cell biology, History, Health, infection and disease
Issue:
Fat
Education levels:
16–19, Continuing professional development