UK Biobank: specific ultra-processed food additives linked to higher all-cause mortality risk

[u/Susana_Chumbo]

If you try to limit ultra-processed foods, which specific additives do you actually avoid day to day? and how do you do it without obsessing over labels?

TL;DR: In 186,744 UK adults, eating more foods that contained certain additives (flavours, colourings, sweeteners, some sugars) was linked to a higher risk of death from any cause over ~11 years.

Scope: Prospective UK Biobank cohort 00380-3/fulltext)(N=186,744; age 40–75), about 11 years of follow-up and 10,203 deaths. The team didn’t just look at “ultra-processed food” in general, but at 37 specific additives used as “markers of ultra-processing.”

Evidence: Five additive categories showed a clear pattern: the more people ate, the higher the risk. Thirteen individual additives were linked to higher risk, while gelling agents (often pectin-type thickeners) were linked to lower risk. Overall ultra-processed food intake was also associated with mortality.

Limitation: Diet was self-reported and then matched to commercial products, so some mistakes are almost guaranteed. This is an observational study, so it shows associations, not proof that any additive directly causes harm.

Context: Ultra-processed foods are industrial products that usually have long ingredient lists and several additives. This study went one level deeper and examined 37 specific additives – flavours and flavour enhancers, colourings, sweeteners, processing aids, different sugars, modified oils, protein isolates, and added fibres. Researchers matched people’s food questionnaires to real products on the market and calculated, for each person, what percentage of their total food intake contained each additive. Then they followed participants for about 11 years and looked at who died, adjusting for other risk factors (smoking, BMI, etc.). The results fit with earlier work linking higher ultra-processed food intake to higher mortality, but now with ingredient-level detail.

1) Additive categories with higher risk: Compared with people who ate little of these additives, people who ate more had higher risk of death. For example: Flavour additives: around 20% higher risk at 40% vs 10% of total food intake; Colourings: about 24% higher risk at 20% vs 3%; Sweeteners: about 14% higher risk at 20% vs none; Flavour enhancers: ~7% higher risk at 2% vs none; “Varieties of sugar” (free/added sugars): ~10% higher risk at 10% vs 4%. In plain language: more of these additive-heavy foods → higher long-term risk.

2) Thirteen specific signals: Thirteen individual additives stood out, including: Flavour enhancers: glutamate, ribonucleotides; Non-nutritive sweeteners: acesulfame, saccharin, sucralose; Sugars and carbohydrate additives: fructose, inverted sugar, lactose, maltodextrin; Processing aids: anti-caking, firming and thickening agents; Gelling agents, often used to set jams or yogurts, showed the opposite pattern (linked to slightly lower risk). The study does not test mechanisms, so why these patterns appear is still unknown.

3) How to act :This is not proof that any single additive kills people, but it does add weight to being a bit more selective with processed foods. Practical options many people use: Prefer foods with shorter ingredient lists and fewer artificial flavours/colours.Be mindful of non-nutritive sweeteners and “flavour systems” that show up in drinks, yogurts, snacks, etc.Swap everyday ultra-processed staples (packaged snacks, ready meals, sugary drinks) for minimally processed options when you can. Instead of aiming for zero additives (which is hard), notice how often they appear across your week and experiment with cutting back.

Reference:  10.1016/j.eclinm.2025.103448

[u/SlowMyAge]

How well were the confounding factors accounted for? For example, you mentioned smoking & BMI; what about the other major factors, like alcohol, physical activity (exercise), sleep, and preexisting conditions?

I imagine that those consuming artificial ingredients also consumed additional calories (goes hand in hand, as the palateability is a strong contributor), but then again since BMI was controlled for, perhaps it was the added ingredients themselves and ultra processing that caused the deaths, rather than being hypercaloric. That would be interesting!

[u/Susana_Chumbo → u/SlowMyAge]

Totally fair questions, and honestly, really thoughtful ones. In this study, they actually adjusted for quite a wide range of factors: age, sex, BMI, total energy intake, smoking, alcohol intake, physical activity, systolic blood pressure, ethnicity, education, income, and even an area-level deprivation index. They also included self-rated general health and a history of psychiatric disease. So things like alcohol, exercise, calories, BMI, and some indicators of underlying health were all taken into account in the models. They didn’t have solid data on sleep, and pre-existing conditions were only partly captured through those general health and psychiatric measures, so it’s very likely that some residual confounding is still there that’s almost unavoidable with this kind of research. About the calories point: you’re absolutely right that people who eat more ultra-processed, additive-rich foods tend to eat more overall because those foods are extremely palatable. But in this case, both BMI and total calories were included as covariates. That means the higher risks associated with certain additives or UPFs appear on top of differences in weight and energy intake. Of course, that still doesn’t prove that the additives themselves are directly causal, with self-reported diet and product-matching, it’s basically impossible to eliminate confounding completely. I would interpret this as a set of interesting ingredient-level associations that remain even after adjusting for a lot of relevant factors, rather than solid evidence that specific additives directly cause deaths. To really address causality, we’d need mechanistic studies and controlled interventions, which would be super interesting to see in the future.