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The debate -

When it comes to the butter vs. margarine debate, everyone has an opinion. Some are quick to dismiss butter for its high level of saturated fat, while others sleight margarine for being an ultra-processed food.

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Which is older? - In terms of how long they have been around, butter definitely comes out on top. This delicious, milk-based ingredient has been around for centuries and is a staple in many food cultures.

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Meteoric rise of margarine -

Margarine, on the other hand, only came on the scene in the early 20th century. It became a popular alternative to butter in the middle of the century, when people began to shun saturated fats.

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The return to butter - In recent years, however, many people have gone back to eating butter instead of margarine, largely due to all the noise about the dangers of ultra-processed foods.

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Complex question -

The truth as to which is better for us–butter or margarine–is unfortunately not simple. Scientists have been researching it for decades, and there is a lot to unpack.

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How butter is made -

It is helpful first to have a basic understanding of how each is made. Butter is a dairy product made by heating milk and separating the cream.

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Components -

It consists of 80-82% milk fat, 16-17% water, and 1-2% milk solids. Different versions of butter are available, such as salted, sweet, and reduced fat.

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How margarine is made -

Margarine, on the other hand, is made by beating oil with water to form a solid product. Several other ingredients are then added, such as emulsifiers and coloring.

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Hydrogenation - Historically, margarine producers added hydrogen to their margarine in order to convert the liquid oils into solid fats, thereby making the product more spreadable.

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Trans fats -

However, they soon realized that this process of hydrogenation can cause the formation of trans fats–a type of unsaturated fat that is associated with poor health outcomes, such as coronary heart disease.

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The risks of trans fats -

Nowadays, therefore, it is possible to buy margarines that have a low or zero percentage of trans fats. However, these are synthetic products that contain many additives.

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Trans fats in margarine -

The presence of trans fats in margarine is one of the main reasons that the dairy-free spread is often considered a less healthy alternative to butter.

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Poor health outcomes - Indeed, studies have shown that a diet high in trans fats is linked to the worst health outcomes. However, we also need to be careful of how much saturated fat (present in butter) we consume.

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Saturated fats -

In general, experts recommend that saturated fats make up no more than 10% of the energy we consume. This is particularly important for people who have risk factors for heart disease.

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Further complexity - The complexity doesn’t stop there, however. Increasingly, scientists are beginning to recognize that not all saturated fats are made the same.

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Fatty acids -

Indeed, saturated fats are made up of individual fatty acids with different chain lengths, which gives each individual fatty acid different properties and different impacts on health.

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Different saturated fats -

This could mean that, for example, the saturated fats in fish are different from the saturated fats in dairy, and the two impact our health in different ways.

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Expert opinion -

According to research by Nita Forouhi, a professor at the University of Cambridge, the saturated fat from meat and butter is linked with a higher risk of heart disease when compared with the fat from fish or fermented dairy products.

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Viewing foods as a whole -

In one BBC interview, Forouhi noted the importance of viewing foods as more than the sum of their nutrient parts: "They have macronutrients, loads of different micronutrients, minerals, vitamins, fiber, salt, additives, and some are fermented."

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Ultra-processed foods -

Another aspect to the butter vs. margarine debate is the classification of the latter as an ultra-processed food (according to the most used classification system).

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UPFs and health -

Ultra-processed foods have been linked in multiple studies with poor health outcomes, such as obesity, type 2 diabetes, and heart disease.

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Lack of research -

However, there are no long-term studies that specifically compare the impact on health of butter versus margarine.

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Existing studies -

Indeed, many of the current studies that look at the health impact of various foods actually lump butter and margarine into one food type, i.e. spreads.

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Substitution analysis -

In order to work out which spread carries a higher risk of developing type 2 diabetes, for example, scientists will need to carry out a proper substitution analysis.

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Counter-argument -

Moreover, it does not make sense to rule out all ultra-processed foods, since some have other health benefits. Margarine, for example, is a good source of vitamin A.

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No clear answer -

Ultimately, the question as to which is better for us, butter or margarine, does not appear to have a simple answer.

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What we know -

It seems clear that opting for foods that are low in saturated fats, higher in polyunsaturated fats, and with no trans fats is the best option.

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Personal choice -

Which spread you choose to slather onto your toast, however, will come down to your personal health needs and eating habits.

Sources: (BBC) (News-Medical)

See also: Everyday foods you didn't know could kill you

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