Butter or Margarine: A 150-Year-Old Dispute – and What the Latest Research Says

Few breakfast-table questions are as old and as stubborn as this one: butter or margarine? One is seen as a natural product steeped in tradition, the other as a technical invention – and over the past 150 years both have repeatedly switched sides when it comes to reputation. Here we sort out where the two spreads come from, what is actually in them and what current research observes.

How a prize competition launched by Napoleon III led to a butter substitute

Butter has accompanied humanity for thousands of years. A Sumerian mosaic dated to around 3000 BC already depicts butter-making; the ancient Greeks and Romans knew this milk fat but used it more as a salve than as food. Only in the late Middle Ages did butter become a widely traded commodity in Central Europe.

Margarine is far younger – and an invention born of necessity. As industrialisation and urbanisation took hold in the 19th century, butter became scarce and expensive. In 1866 the French emperor Napoleon III offered a prize for the development of a durable, inexpensive butter substitute – intended to feed his troops and the poorer urban population. The chemist Hippolyte Mège-Mouriès won the competition and was granted the patent on 15 July 1869. His first "beurre économique" was made from beef tallow, milk and water; he derived the name from the Greek word "margaron" (pearl), because the mass shimmered like mother-of-pearl.

This product still had little in common with today's largely plant-based margarine. The decisive step came in 1902, when the German chemist Wilhelm Normann developed fat hardening: by adding hydrogen (hydrogenation), liquid vegetable oils can be turned into spreadable, solid fats. This made it possible to produce margarine from vegetable oils on an industrial scale for the first time – and it was precisely this process that, decades later, became the heart of the health debate.

What is actually in butter and margarine

Butter is a pure natural product made from cream. It consists of around 80 per cent fat, plus water, small amounts of fat-soluble vitamins and traces of protein, milk sugar and minerals. Its high proportion of saturated fatty acids is characteristic – a direct result of its animal origin. Nothing is added.

Margarine is technically more complex: an emulsion of water together with vegetable oils and fats, usually based on rapeseed or sunflower oil. Added vitamins, emulsifiers and, depending on the recipe, further ingredients such as milk or egg components, starch or salt are common. As a result, its fatty-acid profile shifts towards the unsaturated fatty acids. In terms of calories, the two spreads are practically on a par – reduced-fat margarines aside.

Characteristic	Butter	Margarine
Origin	Cream (animal)	Vegetable oils (mostly rapeseed, sunflower)
Predominant fatty acids	mostly saturated	mostly unsaturated
Processing	unprocessed, nothing added	industrial emulsion, vitamins added
Calorie content	high	comparable (except reduced-fat)

Why margarine had a poor reputation for decades – and what has changed

When suspicion arose in the second half of the 20th century that saturated fats might harm the cardiovascular system, partially hydrogenated vegetable fat was initially regarded as the healthier alternative. This is where trans fatty acids came in: they form when oils are only partially hardened, and harder margarines and baking fats once contained considerable amounts of them – in some cases up to around 20 per cent of the fat content.

In 1990, a controlled feeding study by Mensink and Katan (a randomised crossover trial in healthy adults) showed that trans fatty acids raise LDL cholesterol while lowering HDL cholesterol – a profile the authors rated as at least as unfavourable as that of saturated fatty acids. Later observational studies linked a high trans-fat intake with an increased risk of coronary heart disease. The World Health Organization today classifies industrially produced trans fats as an avoidable risk factor and recommends keeping their share as low as possible.

Crucially, this chapter is largely closed. In April 2008, Switzerland became the second country in the world – after Denmark – to introduce a statutory limit: a maximum of 2 grams of trans fatty acids per 100 grams of fat in vegetable cooking oils and fats. Manufacturers reformulated their products; modern soft margarines today contain practically no appreciable trans fats. Butter was never affected by this reformulation, because it contains no hardened fat – the small amounts of trans fatty acids in butter occur naturally in the rumen of ruminant animals and are considered unproblematic according to current knowledge.

What research observes about saturated fatty acids

The assessment of saturated fatty acids – the predominant fat group in butter – is more nuanced than headlines often suggest. What is clear: it matters less whether saturated fat is simply removed than what it is replaced with.

A comprehensive review by the Cochrane Collaboration (a meta-analysis of randomised controlled trials, 2020) concluded that reducing saturated fat intake over at least two years was associated with a potentially important reduction in combined cardiovascular events – and the more pronounced the reduction, the greater the effect. Replacement with polyunsaturated fatty acids proved a particularly useful strategy; the benefit of replacement with monounsaturated fats remained unclear in this analysis. An earlier meta-analysis of randomised trials (Mozaffarian and colleagues, 2010) had already observed that the targeted exchange of saturated for polyunsaturated fatty acids was associated with fewer coronary events.

These findings explain why the fatty-acid profile of a margarine – more unsaturated, fewer saturated fatty acids – is often regarded as more favourable from a nutritional standpoint. They are not, however, a blank cheque: when saturated fat is replaced with refined carbohydrates, this advantage does not appear.

A large long-term study from 2025 – and how to read it

In March 2025, one of the largest analyses on this topic to date appeared in the journal JAMA Internal Medicine. Researchers evaluated data from 221,054 adults across three long-term US cohorts over a period of up to 33 years. During that time, around 50,900 deaths were recorded.

The result: people with the highest butter consumption had roughly a 15 per cent higher overall mortality risk than those with the lowest. A high intake of plant-based oils – above all soybean, canola and olive oil – was conversely associated with around a 16 per cent lower mortality risk. In a model in which about one tablespoon of butter per day was replaced with plant-based oils, the estimated risk of total and cancer-related mortality was around 17 per cent lower.

These figures sound striking but call for a sober reading. This is an observational study: it shows associations, not cause and effect. Diet was self-reported via questionnaire, and although the researchers adjusted for numerous influencing factors such as smoking, exercise and overall diet, a residual influence of unaccounted-for factors can never be ruled out. The study fits well with the rest of the evidence – it is another piece of the mosaic, but not definitive proof.

What actually matters for fat quality

Taken together, the research reveals a pattern: it is not the label "butter" or "margarine" that decides, but the composition of the fatty acids. A soft, rapeseed-oil-based margarine provides a favourable ratio of unsaturated fatty acids and contains, in alpha-linolenic acid, a plant-based omega-3 fatty acid. Butter scores with its natural, unprocessed character and its aroma.

Both share one gap, however: neither butter nor most margarines provide appreciable amounts of the long-chain omega-3 fatty acids EPA and DHA. The body can convert plant-based alpha-linolenic acid into these long-chain forms only to a limited extent. EPA and DHA classically come from oily sea fish – or, plant-based and directly, from microalgae, where the fish originally take up their omega-3 in the first place. This is precisely where targeted micronutrient sources come in, ensuring a reliable supply independently of which spread you choose.

Safety and everyday use

Both butter and margarine are concentrated fats and therefore energy-dense. From a nutritional standpoint, the same applies to both: as a spread in manageable amounts, embedded in a varied diet. Anyone keeping an eye on their blood lipids will find a sensible option in a soft margarine with a favourable fatty-acid profile or in liquid vegetable oils.

With allergies and intolerances, it is worth checking the ingredient list: butter contains milk components; some margarines contain milk, soy or traces of other allergens. For children, pregnant and breastfeeding people, both spreads are unproblematic in household amounts – in these life stages an adequate supply of omega-3 fatty acids, especially DHA, is particularly relevant, something regularly addressed in nutritional counselling. When buying margarine, it is best to choose soft, rapeseed-oil-based varieties and to watch for the note "partially hydrogenated" on the ingredient list, which would indicate older recipes with a higher trans-fat content.

Conclusion: what is shown – and what remains open

The decades-old dispute of "butter versus margarine" can be viewed more calmly today. The trans-fat problem that earned margarine its poor reputation has been largely solved through reformulation and statutory limits. Research observes fairly consistently that a fatty-acid profile with more unsaturated and fewer saturated fatty acids – as offered by soft plant margarines and vegetable oils – goes hand in hand with more favourable cardiovascular outcomes, provided that saturated fat is actually replaced with unsaturated fat. The large 2025 cohort study fits this picture but, as an observational study, cannot provide causal proof.

Much remains open in the detail: individual margarine recipes differ widely, individual metabolisms respond differently, and the overall diet weighs more heavily than the choice of a single spread. What can be said: there is no reason for dogmatism in either direction – but there are good arguments for paying attention to fat quality in your spread and keeping the supply of long-chain omega-3 separately in view.

This article is for general information and does not replace individual nutritional or medical advice. Food supplements are not a substitute for a varied, balanced diet and a healthy lifestyle.