I had a patient last year. Let's call her M. She's 38, vegetarian, does yoga three times a week, doesn't smoke, barely drinks. On paper, she's the definition of healthy.
We ran her biological age panel. It came back at 43.
Five years older than her birth certificate. She was confused. "I eat so clean, Doc. I don't even eat meat."
So I asked her to walk me through a typical day of eating. Breakfast was instant oats with a plant-based protein shake. Lunch was often a packet of vegetarian cup noodles at her desk. Afternoon snack: a "protein bar" from the convenience store. Dinner: sometimes a Beyond Meat burger with some frozen fries. Supper: biscuits and 3-in-1 Milo.
Every single one of those items is ultra-processed.
"But it's vegetarian," she said. "It's supposed to be healthier."
This is one of the biggest blind spots I see in clinic. People who genuinely care about their health, who are making real effort, but whose diets are quietly dominated by foods that are accelerating their ageing at the cellular level. And the research that's piled up over the past year makes this impossible to ignore.
It doesn't matter if it's organic, vegan, gluten-free, or "high protein." If it's ultra-processed, the evidence says it's making you age faster.
What Even Counts as "Ultra-Processed"?
Before we get into the data, let's get clear on what we're actually talking about. Because "processed food" is one of those terms that confuses everyone.
Scientists use something called the NOVA classification, developed by Professor Carlos Monteiro at the University of São Paulo. It splits food into four groups based on how much industrial processing they've undergone.
Group 1 is unprocessed or minimally processed. Fresh vegetables, fruits, eggs, plain rice, fresh meat, fish. Basically, food that looks like it did when it came out of the ground or off the animal.
Group 2 is processed culinary ingredients. Think cooking oils, butter, sugar, salt, flour. You use these to cook Group 1 foods.
Group 3 is processed foods. Canned vegetables with added salt. Freshly baked bread from a bakery with a simple ingredient list. Cheese. Smoked fish. These are Group 1 foods modified with Group 2 ingredients. Still recognisable.
Group 4 is ultra-processed. This is where things get interesting. These are industrial formulations made mostly or entirely from substances derived from foods plus additives. They contain ingredients you would never use in a home kitchen: hydrogenated oils, high-fructose corn syrup, protein isolates, emulsifiers, thickeners, artificial flavours, colours.
Quick test: look at the ingredient list. If it contains things your grandmother wouldn't recognise as food, it's probably ultra-processed.
Ultra-Processed (NOVA Group 4)
Instant noodles, packaged biscuits, sugary drinks, 3-in-1 beverages, mass-produced bread, protein bars, plant-based "meats," frozen ready meals, breakfast cereals, flavoured yoghurts, packet sauces, chicken nuggets, fish balls with additives
Real Food (NOVA Groups 1-3)
Fresh fruit, vegetables, rice, noodles made from flour and water, eggs, tofu, fresh fish, chicken, home-cooked curry, plain yoghurt, nuts, traditional kaya, freshly made roti prata, chye tow kway made from scratch
The Singapore Data Is In. And It's Not Great.
This is the part that hit close to home for me as a doctor practising in Singapore.
A study published in the Nutrition Journal analysed data from the Singapore Chinese Health Study, one of the largest and longest-running cohort studies in Asia. Researchers followed 62,197 middle-aged and older Singaporean Chinese adults from the 1990s through to 2022. That's nearly three decades of follow-up.
They classified every participant's diet using the NOVA system and tracked who died, and from what.
Now, a 6% increase in all-cause mortality might not sound dramatic. But remember: this was after adjusting for age, smoking, exercise, BMI, and overall diet quality. Meaning even people who had a decent diet overall still saw increased risk if a larger proportion of it was ultra-processed.
And here's the part that matters for us locally. In the Singapore Chinese Health Study, the main ultra-processed culprits were sweetened beverages (53.7% of UPF intake), ultra-processed cereals and starchy foods (30%), sugary products (5.5%), and processed meats (4.5%). Think about how many of those are sitting in your kitchen right now. The packet drinks, the instant cereals, the flavoured oat milks.
What's unique about this study is that it's one of the first to show these effects in an Asian population. Most of the earlier UPF research came from Europe and the US. Now we know: this isn't a Western diet problem. It's our problem too.
The Global Picture Is Even More Alarming
The Singapore study didn't land in isolation. It arrived alongside a wave of research that, taken together, paints a really clear picture.
In March 2025, the most comprehensive meta-analysis to date was published in Systematic Reviews. Researchers pooled data from 18 prospective cohort studies covering 1,148,387 people and 173,107 deaths. The conclusion: people with the highest ultra-processed food consumption had a 15% higher risk of dying from any cause compared to those who ate the least. And for every 10% increase in the proportion of ultra-processed food in someone's diet, the risk of death went up by 10%.
Then in November 2025, The Lancet published a landmark three-paper series linking ultra-processed food to harm across "nearly every organ system." The researchers reviewed over 100 studies and found consistent associations between UPF consumption and type 2 diabetes, cardiovascular disease, chronic kidney disease, Crohn's disease, depression, and all-cause mortality.
And earlier in 2025, a study in the American Journal of Preventive Medicine estimated premature deaths attributable to UPF consumption across eight countries. In the United States alone, 124,000 premature deaths per year were attributable to ultra-processed food. In the UK, up to 14% of all premature deaths were linked to UPF intake.
These numbers aren't fringe science. This is The Lancet. This is data from over a million people across multiple continents. The signal is consistent and it's strong.
It's Not Just Shortening Your Life. It's Ageing Your Cells.
This is the part that really got my attention as a longevity doctor.
A 2025 study published in GeroScience examined 172,225 participants from the UK Biobank. The researchers didn't just look at whether people died. They measured biological ageing using something called PhenoAge, an algorithm that estimates how old your body really is based on nine blood biomarkers including albumin, C-reactive protein, glucose, and white blood cell counts. These are the same kinds of markers we measure in our biological age panels at the clinic.
Here's what they found. Biological ageing mediated 13.9% of the association between ultra-processed food consumption and all-cause mortality. In other words, nearly one-seventh of the reason UPF kills people is because it literally makes your body older at the cellular level.
Think of it like this. You know how some people look and feel older than their age, while others seem younger? Ultra-processed food is quietly pushing you into the first category. Not through one dramatic event, but through thousands of small inflammatory insults, day after day, meal after meal.
The same study found that artificial sweeteners and sugary beverages were the worst offenders, with biological ageing mediating 27.5% and 8.3% of their mortality effects respectively. So that "zero sugar" diet drink you're reaching for thinking it's the healthier option? The data suggests otherwise.
And this isn't the only study showing this. A separate analysis of 64,690 UK Biobank participants found that for every additional serving of ultra-processed food per day, telomere length (the protective caps on the ends of your chromosomes that shorten with ageing) decreased measurably. Shorter telomeres are associated with accelerated ageing and age-related disease.
Why Does Ultra-Processed Food Do This?
This is the question I get most often. What is it about these foods that's actually causing the damage?
The Lancet series addressed this directly. And the answer is: it's not just about the nutrients. It's the processing itself.
Ultra-processed foods tend to be energy-dense but nutrient-poor. They lack the phytochemicals, fibre, and micronutrients that protect against disease. But beyond what's missing, there's what's been added and altered. The industrial processing destroys the physical structure of the food matrix, meaning your body absorbs calories faster, blood sugar spikes harder, and you don't feel full as quickly.
The emulsifiers and artificial additives may also directly damage the gut lining, promote chronic low-grade inflammation, and disrupt the gut microbiome. We see this regularly in the GI-MAP stool tests we run at the clinic. Patients with high ultra-processed food intake almost invariably have markers of gut dysbiosis, even when they have no digestive symptoms.
Then there's the metabolic impact. Ultra-processed foods drive insulin resistance, visceral fat accumulation, and chronic inflammation. These are the exact biological pathways that accelerate ageing. It's not one mechanism. It's all of them, working together, compounding over years.
The Singapore Trap
Here's something that doesn't get talked about enough. Singapore's food environment makes this harder than it should be.
Research shows that about 60% of our dietary intake comes from processed foods. And while our hawker centres are brilliant (78% of food service transactions happen there), the reality is that even hawker food is increasingly using ultra-processed ingredients. Pre-made sauces, processed meats, instant stock powders, MSG-heavy flavour pastes. The uncle making your chicken rice might be using a sauce packet from a factory rather than making it from scratch.
Add to that our convenience store culture, our kopi 3-in-1 habit, the packet drinks in every office pantry, and the absolute explosion of "healthy" snack bars and protein shakes marketed at health-conscious millennials. Many of the foods being sold as health foods are some of the most ultra-processed items on the shelf.
M, my patient from earlier, was a perfect example. Everything she ate was marketed as healthy. Vegetarian. High protein. Added vitamins. But the ingredient lists were paragraphs long, filled with isolates, stabilisers, and flavourings. The packaging was doing a brilliant job of hiding what the food actually was.
What to Actually Do About It
I'm not here to tell you to never eat a packet of instant noodles again. That's not realistic, and perfection isn't the goal. But there are practical swaps that make a real difference.
Read the ingredient list, not the marketing
Ignore the front of the packet. Turn it over. If you see ingredients like maltodextrin, soy protein isolate, hydrogenated oils, emulsifiers (E471, E472), artificial sweeteners (sucralose, aspartame, acesulfame-K), or flavour enhancers, put it back. The shorter the ingredient list, the better. If you can picture every ingredient as a real food, you're probably fine.
Swap your breakfast first
Breakfast is where most of the damage happens. Instant oats, cereal, protein shakes, kaya toast with packet spread. Try instead: two eggs any style, a piece of fruit, and some nuts. Or congee with a simple egg and spring onion. If you want oats, buy plain rolled oats (not instant) and cook them yourself with real milk and fresh berries.
Choose the right hawker stalls
Not all hawker food is equal. A yong tau foo stall where you can see fresh vegetables being blanched is very different from a stall selling pre-fried processed fish balls and crabstick. Steamed fish, clear soups, stir-fried vegetables with garlic, sliced fish bee hoon. These are minimally processed meals. They exist at almost every hawker centre.
Ditch the packet drinks
This is the single biggest win for most Singaporeans. Sweetened beverages accounted for over half of ultra-processed food intake in the Singapore Chinese Health Study. Replace the packet chrysanthemum tea, the 3-in-1 kopi, and the canned coffee with plain water, unsweetened tea, or kopi-O kosong. You'll feel the difference within a week.
Cook one meal a day from scratch
You don't need to become a home chef. But one meal a day made from recognisable ingredients shifts the balance. A simple stir-fry with fresh vegetables, tofu or chicken, garlic, soy sauce, and rice takes 15 minutes. That's less time than waiting for a food delivery. Make extra. Eat leftovers for lunch the next day.
Be suspicious of "health foods"
Protein bars, plant-based meats, meal replacement shakes, zero-sugar flavoured drinks. Many of these are among the most ultra-processed products available. A handful of almonds has more protein than most protein bars and zero additives. Real food doesn't need a health claim on the packaging.
What Happened With M.
We worked with M over four months. We didn't put her on a "diet." We didn't count calories. We just systematically replaced the ultra-processed items in her routine with real food equivalents. Same convenience, same vegetarian preference, just actual food instead of industrial products.
Instant oats became overnight oats made with real rolled oats and fresh fruit. Cup noodles became a yong tau foo bowl from the hawker centre near her office. The protein bar became a small box of mixed nuts she kept in her desk drawer. The Beyond Burger became home-cooked dhal with rice.
Four months later, we re-tested. Her biological age dropped from 43 to 39. Four years younger. Her inflammatory markers came down significantly. Her fasting insulin improved. Her gut microbiome diversity, which we measured with a GI-MAP test, showed clear improvement.
She didn't exercise more. She didn't sleep differently. She didn't take any new supplements. She just stopped eating things pretending to be food and started eating actual food.
The best diet for longevity isn't complicated. It's the one your great-grandparents would recognise. Real ingredients. Simple preparation. No ingredient list required.
If you're doing everything "right" and your numbers still aren't where you want them, take a hard look at how processed your diet really is. The answer might be hiding in plain sight, in the ingredient lists you've never bothered to read.
And if you want to know exactly how your diet is affecting your biological age, inflammatory markers, and gut health, a comprehensive longevity assessment can give you those answers. Real data. Not guesswork.
- Tan JYJ, Neelakantan N, Koh WP, van Dam RM. Consumption of ultra-processed foods and risk of all-cause and cause-specific mortality: the Singapore Chinese Health Study. Nutrition Journal. 2025;24:72. doi:10.1186/s12937-025-01219-0
- Moradi S, Mohammadi H, Nachvak SM, et al. Ultra-processed foods and risk of all-cause mortality: an updated systematic review and dose-response meta-analysis of prospective cohort studies. Systematic Reviews. 2025;14:71. doi:10.1186/s13643-025-02800-8
- Qu Y, Hu N, Zhang H, et al. Ultra-processed foods, biological ageing, and all-cause mortality risk: a prospective cohort study using 172,225 participants from UK Biobank. GeroScience. 2025. doi:10.1007/s11357-025-01810-7
- Nilson EAF, Mauger C, Mantilla-Herrera AM, et al. Premature mortality attributable to ultraprocessed food consumption in 8 countries. American Journal of Preventive Medicine. 2025;69(3):437-445. doi:10.1016/j.amepre.2025.02.018
- Monteiro CA, Cannon G, Lawrence M, et al. Ultra-processed foods and human health: the main thesis and the evidence. The Lancet. 2025;406(10468):1841-1857. doi:10.1016/S0140-6736(25)01565-X
- Li C, Luo J, Xu Z, et al. Association between ultra-processed food consumption and leucocyte telomere length: a cross-sectional study of UK Biobank. The Journal of Nutrition. 2024;154(7):2346-2357. PMID: 38735573