The sugar industry paid scientists to blame fat

Yes, the sugar industry funded influential 1960s research that downplayed sugar's role in heart disease and shifted attention towards fat. Internal documents analysed in 2016 showed that the Sugar Research Foundation paid Harvard scientists for a literature review that criticised fat and cholesterol while treating sugar evidence more favourably. That history matters, but it does not mean saturated fat is harmless or that modern nutrition science is explained by one conspiracy.¹

What actually happened

In 2016, Cristin Kearns, Laura Schmidt and Stanton Glantz published a historical analysis of internal sugar-industry documents. They reported that the Sugar Research Foundation, now the Sugar Association, sponsored a 1967 New England Journal of Medicine review by Harvard nutrition scientists that examined dietary factors in coronary heart disease.¹

The review was not labelled as industry-funded. According to the document analysis, the foundation set the review's objective, contributed articles for inclusion, received drafts and paid the authors. The resulting review questioned studies linking sucrose to coronary heart disease and placed greater emphasis on dietary fat and cholesterol.

At the time, disclosure rules were much weaker than today. That is part of why the story feels shocking now. Modern readers expect funding and conflicts to be explicit. In the 1960s, influential review articles could shape the scientific conversation without the same transparency.

How fat took the blame

The 1960s were a key period in heart-disease research. Scientists were debating the roles of dietary fat, saturated fat, cholesterol, sugar, calories, smoking and other risks. Industry-funded work did not invent concern about fat. There were real reasons to study fat and cholesterol. But the sugar documents show how a commercial actor could amplify one explanation while making another look weaker.

That matters because public-health messages became simplified. Low-fat products multiplied, often with added sugars or refined starches. People were told to reduce fat while the quality of carbohydrate received less attention. The public heard "fat is bad" more clearly than "diet pattern, energy balance, fibre, food processing and metabolic health all matter".

The sugar industry used similar strategies in dental research. A 2015 PLOS Medicine paper analysed internal documents and reported that industry efforts influenced the US National Institute of Dental Research's caries programme, steering attention towards interventions other than reducing sugar consumption.² The pattern was familiar: fund science, shape questions, emphasise alternatives, and protect sales.

What the story does not prove

The sugar-industry story does not prove that fat is innocent. Saturated fat can raise LDL cholesterol in many people, and LDL is causally involved in atherosclerotic cardiovascular disease. The better lesson is that single-nutrient blame is dangerous. A diet can be low-fat and poor if it is built from sugary cereals, white bread and ultra-processed snacks. A diet can be low-sugar and poor if it is high in processed meats, low in fibre and excessive in calories.

It also does not prove that sugar alone caused the obesity or diabetes epidemics. Sugary drinks, sweets and desserts are easy to overconsume, but weight and metabolic disease are shaped by food environment, poverty, sleep, activity, stress, medication, genetics, alcohol, marketing and portion size. The history should make us sceptical of simple stories, including anti-sugar stories that sell a product.

Finally, it does not mean all nutrition research is useless. It means research should be read with attention to funding, comparator diet, duration, adherence, endpoints, conflicts, publication bias and whether results are replicated independently.

What the evidence says now

Modern guidance usually focuses on both sugar and saturated fat, not one or the other. WHO recommends reducing free sugars, especially because of weight gain and dental caries, with a strong recommendation to reduce free sugars to less than 10% of total energy intake and a conditional recommendation for below 5% where possible.³

In the UK, the Scientific Advisory Committee on Nutrition recommended that free sugars should not exceed 5% of total dietary energy intake, and that sugar-sweetened drinks should be minimised in children and adults.⁴ NHS public guidance similarly warns that too much sugar can contribute to weight gain and tooth decay.⁵

NHS guidance on fats still advises reducing saturated fat and replacing it with unsaturated fats where possible.⁶ The modern message is not "eat unlimited fat". It is: reduce free sugars, avoid sugary drinks, improve carbohydrate quality, increase fibre, choose unsaturated fats more often, and judge the whole diet.

That usually means boring swaps rather than ideology: water instead of sugary drinks, yoghurt and fruit instead of sweet snacks, oats or wholegrains instead of refined cereal, olive oil or nuts instead of butter-heavy snacks, and fewer ultra-processed foods that combine sugar, fat, salt and softness in ways that make overeating easy.

How to read nutrition claims

When a headline says "sugar causes heart disease" or "fat was never bad", ask five questions. Who funded the study? Was it a randomised trial, cohort, mechanistic study, animal study or historical analysis? What was the comparator? Was the outcome a real disease event, a blood marker or a short-term appetite measure? Does the claim fit the wider evidence?

Also ask what the claim is selling. Low-fat snack foods, keto bars, glucose monitors, detoxes, supplements and anti-sugar programmes all have commercial incentives. A conflict does not automatically make a claim false, but it should lower your tolerance for vague wording.

Modern conflict-of-interest statements are better than 1960s disclosure, but they are not a magic shield. A study can disclose funding and still be designed around a weak comparator, a short follow-up, a surrogate marker or a subgroup that makes the sponsor's product look useful. Look for independent replication, hard outcomes where possible, and whether the authors discuss limitations plainly. The most trustworthy nutrition claims usually survive contact with different methods, populations and research groups.

Use the health library to understand cholesterol, insulin resistance and metabolic health, and insights when a nutrition headline feels too neat. If supplements, glucose hacks or fat-loss products are part of the pitch, the stack builder can help screen for overclaiming and interaction risks.

What to ask your GP

This history is interesting, but your personal risk still needs numbers. If you need help preparing for a metabolic health appointment, Start here.

The sugar industry story is a warning about captured science and oversimplified public messages. It is not permission to replace one simplistic villain with another. The better lesson is to follow the evidence, check conflicts and judge diet patterns instead of slogans.

This article is educational and does not constitute medical advice, diagnosis, or a treatment recommendation. Medication uses described as “off-label” are not licensed for that purpose in the UK and should only be considered under qualified clinical supervision. Always speak to your GP, pharmacist, or a registered specialist before starting, stopping, or changing any treatment. If you have severe or alarm symptoms - unintentional weight loss, blood in your stool, difficulty swallowing, persistent vomiting, a fever, or severe pain - seek urgent medical care.